#but instead they linked with only other mollusks

[rebisgender]

I can’t believe I have brain worms over a living armor mollusk (from dunmeshi) society. they would most likely be a culture of blacksmiths and mercenaries, and chances are they would communicate via sign language or or maybe telepathy if they somehow learn to utilize magic. but I need to know more. Can they leave the armor? does it have to be metal? how do they eat? I need to know more.

[bethanythebogwitch]

I recently found out a show I liked is 10 years old now so to not be the oldest thing on this blog I'm talking coelacanths for Wet Beast Wednesday. Coelacanths are rare fish famed for being living fossils. While that term is highly misleading, it is true that coelacanths are among the only remaining lobe-fined fish and were thought to have gone extinct millions of years ago before being rediscovered in modern times.

(image id: a wild coelacanth. It is a large, mostly grey fish with splotches of yellowish scales. Its fins are attached to fleshy lobes. It is seen from the side, facing the top right corner of the picture)

Coelacanth fossils had been known since the 1800s and they were believed to have gone extinct in the late Cretaceous period. That was until December 1938, when a museum curator named Marjorie Courtenay-Latimer was informed of an unusual specimen that had been pulled in by local fishermen. After being unable to identify the fish, she contacted a friend, ichthyologist J. L. B. Smith, who told her to preserve the specimen until he could examine it. Upon examining it early next year, he realized it was indeed a coelacanth, confirming that they had survived, undetected, for 66 million years. Note that fishermen living in coelacanth territory were already aware of the fish before they were formally described by science. Coelacanths are among the most famous examples of a lazarus taxon. This term, in the context of ecology and conservation, means a species or population that is believed to have gone extinct but is later discovered to still be alive. While coelacanths are among the oldest living lazarus taxa, they aren't the oldest. They are beaten out by a genus of fly (100 million years old) and a type of mollusk (over 300 million years old).

(image: a coelacanth fossil. It is a dark brown imprint of a coelacanth on white rock. Its skeleton is visible in the imprint)

Coelacanths are one of only two surviving groups of lobe-finned fish along with the lungfishes. Lobe-finned fish are bony fish notable for their fins being attached to muscular lobes. By contrast, ray-finned fish (AKA pretty much every fish you've ever heard of that isn't a shark) have their fins attached directly to the body. That may not sound like a big difference, but it actually is. The lobes of lobe-finned fish eventually evolved into the first vertebrate limbs. That makes lobe-finned fish the ancestors of all reptiles, amphibians, and mammals, including you. In fact, you are more closely related to a coelacanth than a coelacanth is to a tuna. Coelacanths were thought to be the closest living link to tetrapods, but genetic testing has shown that lungfish are actually closer to the ancestor of tetrapods.

(image id: a scientific diagram depicting the taxonomic relationships of early lobe-finned fish showing their evolution to proto-tetrapods like Tiktaalik and Ichthyostega, to true tetrapods. Source)

There are two known living coelacanth species: the west Indian ocean coelacanth (Latimeria chalumnae) and the Indonesian coelacanth (L. menadoensis). Both are very large fish, capable of exceeding 2 m (6.6 ft) in length and 90 kg (200 lbs). Their wikipedia page describes them as "plump", which seems a little judgmental to me. Their tails are unique, consisting of two lobes above and below the end of the tail, which has its own fin. Their scales are very hard and thick, acting like armor. The mouth is small, but a hinge in its skull, not found in any other animal, allows the mouth to open extremely wide for its size. In addition, they lack a maxilla (upper jawbone), instead using specialized tissue in its place. They lack backbones, instead having an oil-filled notochord that serve the same function. The presence of a notochord is the key characteristic of being a chordate, but most vertebrates only have one in embryo, after which it is replaced by a backbone. Instead of a swim bladder, coelacanths have a vestigial lung filled with fatty tissue that serves the same purpose. In addition to the lung, another fatty organ also helps control buoyancy. The fatty organ is large enough that it forced the kidneys to move backwards and fuse into one organ. Coelacanths have tiny brains. Only about 15% of the skull cavity is filled by the brain, the rest is filled with fat.

(image id: a coalacanth. It is similar to the one on the above image, but this one is blue in color and the head is seen more clearly, showing an open mouth and large eye)

One of the reasons it took so long for coelacanths to be rediscovered is their habitat. They prefer to live in deeper waters in the twilight zone, between 150 and 250 meters deep. They are also nocturnal and spend the day either in underwater caves or swimming down into deeper water. They typically stay in deeper water or caves during the day as colder water keeps their metabolism low and conserves energy. While they do not appear to be social animals, coelacanths are tolerant of each other's presence and the caves they stay in may be packed to the brim during the day. Coelacanths are all about conserving energy even when looking for food. They are drift feeders, moving slowly with the currents and eating whatever they come across. Their diet primarily consists of fish and squid. Not much is known about how they catch their prey, but they are capable of rapid bursts of speed that may be used to catch prey and is definitely used to escape predators. They are believed to be capable of electroreception, which is likely used to locate prey and avoid obstacles. Coelacanths swim differently than other fish. They use their lobe fins like limbs to stabilize their movements as they drift. This means that while coelacanths are slow, they are very maneuverable. Some have even been seen swimming upside-down or with their heads pointed down.

(image: an underwater cave wilt multiple coelacanths residing in it. 5 are clearly visible, with the fins of others showing from offscreen)

Coelacanths are a vary race example of bony fish that give live birth. They are ovoviviparous, meaning the egg is retained and hatches inside the mother. Gestation can take between 2 and 5 years (estimates differ) and multiple offspring are born at a time. It is possible that females may only mate with a single male at a time, though this is not confirmed. Coelacanths can live over 100 years and do not reach full maturity until age 55. This very slow reproduction and maturation rate likely contributes to the rarity of the fish.

(image: a juvenile coelacanth. Its body shape is the same as those of adults, but with proportionately larger fins. There are green laser beams shining on it. These are used by submersibles to calculate the size of animals and objects)

Coelacanths are often described as living fossils. This term refers to species that are still similar to their ancient ancestors. The term is losing favor amongst biologists due to how misleading it can be. The term os often understood to mean that modern species are exactly the same as ancient ones. This is not the case. Living coelacanth are now known to be different than those who existed during the Cretaceous, let alone the older fossil species. Living fossils often live in very stable environments that result in low selective pressure, but they are still evolving, just slower.

(image: a coelacanth swimming next to a SCUBA diver)

Because of the rarity of coelacanths, it's hard to figure out what conservation needs they have. The IUCN currently classifies the west Indian ocean coelacanth as critically endangered (with an estimated population of less than 500) and the Indonesian coelacanth as vulnerable. Their main threat is bycatch, when they are caught in nets intended for other species. They aren't fished commercially as their meat is very unappetizing, but getting caught in nets is still very dangerous and their slow reproduction and maturation means that it is long and difficult to replace population losses. There is an international organization, the Coelacanth Conservation Council, dedicated to coelacanth conservation and preservation.

(image: a coelacanth facing the camera. The shape of its mouth makes it look as though it is smiling)

[pleistocene-pride]

Oviraptor is an extinct genus of oviraptorid dinosaur that lived throughout what is now Mongolia during the Campanian and Maastrichtian Stages of the Cretaceous period some 78 to 70 M.Y.A. The first remains of Oviraptor consisting of a mostly complete skeleton with a badly crushed skull which was found lying over a nest of approximately 15 eggs were unearthed from reddish sandstones of the Late Cretaceous Djadokhta Formation of Mongolia in 1923 by a North American paleontology expedition led by Roy Chapman Andrews. This specimen would be formally named and described a year later by Henry Fairfield Osborn in 1924. Because the skull of the specimen was separated from the eggs by only 10 cm of sediment Osborn interpreted Oviraptor as a dinosaur with egg-eating habits, naming the animal Oviraptor which is Latin for "egg seizer" or "egg thief”. The specific name, philoceratops, is intended as "fondness for ceratopsian eggs" which is also given as a result of the initial thought of the nest pertaining to Protoceratops or another ceratopsian. However in the 1990s, the discovery of numerous additional specimens including nesting and nestling oviraptor specimens proved that the initial specimen wasn’t an oviraptor stealing the eggs of another dinosaur, but instead it was a mother oviraptor trying to protect her own nest from a sandstorm. Reaching around 5-6ft in length, 2.5 to 3.5ft tall, and 70-90lbs in weight, oviraptor was a bipedal creature which sported a short, curved, toothless beak and prominent head crest. It had a covering of feathers over its entire body and a pygostyle: ‬several fused vertebrae at the base of the tail that in modern birds is used as a support for tail feathers.‭ With the egg stealing idea now debunked it is believed oviraptor had a much more diverse omnivorous diet comprised of leaves, berries, fruit, nuts, seeds, mollusks, worms, small vertebrates, insects, crustaceans, and other arthropods.

Art work links:

https://twitter.com/Cynderen/status/1486132223833260038/photo/1

http://novataxa.blogspot.com/2020/12/oviraptorosaur.html

https://www.pinterest.com/pin/564920347004490660/

https://nathan-e-rogers.tumblr.com/post/648194189622935552/oviraptorid-adult-and-chicks-late-cretaceous

[insomniamamma]

Rain: Ezra X F!Reader w/Cee

A/N: Prickle ‘verse. Takes place after Prickle but before Clean Dirt. Can be read as a one shot. Reader is established crew with Ezra and Cee. This was written for @autumnleaves1991-blog​ ‘s Writer Wednesday. I am woefully behind. I legit don’t understand how some of you write fics so fast!

Warnings: Mentions of war, a little bit of angst, but mostly gentle fluff. Feelings.

            "Hey, Ez," Ezra is engrossed in grading the latest haul, testing for clarity and hardness.  The surface of CJ's World is cut through with oxbow rivers, fantastic hoodoos of striated sandstone slashed with valleys deeper than any found in Sol system. You're digging for fossils. These rusty carved out plateaus were once the bed of an ancient ocean. Through some trickery of mineralization and chemistry the fossils of CJ's world shine like the fire opals of Old Terra. Big or small, they all have value.           "Ezra," says Cee, "She's doing it again."           "Doing what, birdie?" Ezra takes off the loupe and rubs at his eyes. Rain pelts on the tent, even sheltered the humidity soaks through.           "Look." Ezra draws open the tent flap and sees you, standing in the rain, your head tilted up, no gentle shower this, rain that pelts down hard, turns the view across the sharp-cut canyons to silver curtains. Your clothes are plastered to you like a second skin. The rain actually aids your cause, washing away loose sediment, making the fossils easier to get to. You bow your head and let the stinging rain hit the back of your neck, let it fall on your closed eyes, your outspread arms. You laugh at the sky.

           "What do you know about Falnost?" Cee's eyes go distant for a beat. She has a memory to rival Central computers.

           "Hmmm..about two thirds standard grav, class C5, would've rated lower if not for it's primary. Dustball."             "Mmm-hmm."             "She's not used to real weather," says Cee.             "Observant as ever," says Ezra. The rain is not gentle. It is chilly and hits your skin like handfuls of flung sand, but is so different from anything you've known, so new that you can't help but stand there with a huge, dumb grin plastered on your face, even as your teeth chatter with the cold. Ezra comes and gets you.             "C'mon, Artichoke, while the rain does feel slinky and delicious it is not worth hypothermia."             "Sorry, Ez," you say and allow him to take your hand and lead you back to shelter. This has become something of a habit. Many worlds in the fringe are dustballs like the one you fled, algae and fungus growing on every bit of pipe that condensation beads on. On Falnost they had a deal with the ice-miners, discounted accommodations on world or on station in exchange for chunks of ice from your primary's lush rings de-orbited, burning and evaporating as they fell. The idea was that, eventually, there would be moisture enough in the atmosphere to trigger rains. Someday Falnost will have an ocean, but you won't be there for it, half your life spent harvesting rills of water from sail-traps, careful irrigation channels covered over with plastic sheeting, calorie vs water consumption ratios discussed every planting season. How many credits do we net vs wha† we have to spend? You got fucking sick of dreaming of an ocean your great grandchildren might paddle in. You skimmed enough to buy your way off world and since then you have seen things that you never would have believed as a child.            The first time you heard thunder was on a world called Ingwy. Your first  thought was artillery. Ingwy was a contested world, Karoclan and Lussia Collective skirmishing over land rights, while small stakes droppers like you and Ez and Cee swooped in to reap the spoils while the big corps and clans fought each other.  It was the middle of the night and you were on your feet instantly, railgun in hand, screaming that there was incoming, to take cover. Someone had flicked on a utility light hanging from a cord that swung, illuminating the inside of the tent in sickening arcs, and there's another explosion, this one so loud you feel the pressure change in your ears, hear your own voice crying out in tandem, white hot light even through the thick weave of the tent.           "It's just thunder," Ezra yells over the sound of rain slamming against the tent.           "That was an explosion!" He presses gently on your arm until you lower the rails.           "It's just loud," says Ezra, "It can't hurt us. We're safe here. Put the gun down." You set on the edge of your cot and put your face in your hands.           "Kevva. You must think I'm the dumbest dirt-farmer this side of the Great Arm." The cot dips as Ezra sits beside you.           "Not at all," he says, squeezes your shoulder, "I come from a backwater as well. First time I ever saw a proper ocean I nearly lost my breakfast right there on the beach."  Thunder peals again and you flinch, shrink against him slightly.            "Static electricity," says Ezra, "That's all it is. Builds up in the clouds and discharges into the ground." He keeps his hand on you as he speaks, fingers gently squeezing the juncture of your neck and shoulder, "The sound you hear is the air in the path of the lightning instantly heating and expanding. It makes a sonic shock wave, like any explosion."            "Like the boom when ships lift," you say.            "Just like that, Artichoke," he says, "Storm's already moving off, see?" The rain pelting the tent has settled into a steady drone. Thunder grumbles, a low, almost soft sound, not the air-rending explosion that shocked you out of sleep.            "We should try to rest," says Ezra, gives your shoulder one more firm squeeze and a little shake, and when you look up, he's smiling, dimple just beginning to sink into his cheek.             "Yeah," you say, "Okay." He kills the utility light and settles into his cot. You can hear the music from Cee's headphones, the tinny, fast pop she favors, threaded through the white noise of the falling rain. She slept through the whole thing.

            The ancient life of CJ's world favored heptagonal symmetry, long-dead mollusks like seven-sided shields shine out of the rusty ground, the smallest the size of a fingernail, the largest the size of dinner plates. This is a good deposit. The small ones are fashioned into jewelry and buttons.            "They take these great big ones and slice them micron thin," says Ezra, "Use them for window-glass in the temples of the Ephrate. They say it is like standing inside Kevva's very beating heart."           "I can see why," says Cee, and so do you. The minerals that limn the shells shine translucent red with brilliant streaks of orange, yellow and even thin threads of green and blue.           "They say that Kevva's first heart-beat ignited the explosion that became the universe," says Ezra.           "You really believe that?" Asks Cee.           "I don't know if believe is the right word," says Ezra, "We all grew up with these stories, why my grandmother..." You smile and tune him out. The back and forth banter between Cee and Ezra is a pulse that underlies every harvest. Cee has grown more talkative with each drop. Their relationship has a growing ease to it. You don't know exactly what happened between them before you joined up, but Cee's initial skittishness and Ezra's new healed scars tell a story you can guess the shape of. You let their conversation fade into the background, focus on the work of your hands, the meticulous scrape of soft sediment away from the hard glitter of the fossil, working around the seven sided edge, loosen enough up to get your fingers under the shell and you can pry it out, focus on the sounds of the world around you, no birds on CJ's world, but there is a range of bug-music, hidden in crevasses in the midday heat, all metallic clicks and creaks. Your rail-gun rests within easy reach, as always. You worm your fingers under the edge of the shell, wiggling it like a loose tooth, pops out of the sediment suddenly and you plop on your ass in the sandy dirt.           "You all right there, Artichoke?" Ezra grins at you.           "I'll recover." You dust yourself off and take your prize over to the tub that sits in the shadow of the pod. Further cleaning and grading can be done after dark. Nights  are long at this latitude. You stretch in the sunlight. This job is a milk-run compared to other drops, but hunkering in the dirt still hurts your knees and you feel every bit of it when you stand. There's a familiar sound, like a rumbling stomach, thunder, you think and glance up.          "Ezra!" Your voice is urgent and sharp and he's scrabbling up in a heartbeat, hand on the thrower at his hip, but when he stands there is only you pointing out across the vast expanse of sharp-carved valleys and hoodoos, lined in sharply delineated shadows and rusted cliffs where the light catches. The rainbow swoops skyward into grey cloud-bellies, a luminous curtain against the grey clouds, distant rain falling across the canyons.

        "Ezra, look!" Ezra exhales, tension leaching out of his shoulders. His hand drops away from the thrower.          "Oh, hey, a rainbow," says Cee. You lower your arm and just stare, transfixed at the glowing phantasm, brightening and dimming with the movement of clouds between it and the sun.           "It's beautiful," says Ezra. But he's not looking at the rainbow. He's looking at you. Your eyes are wide, lit up with wonder, an unconscious smile creeping across your face, crinkling the corners of your eyes. The stiff professionalism that you wear as close as your body armor momentarily set down, forgotten. Ezra's heart squeezes. There you are, he thinks. He can count on his one hand the number of times he's seen you smile like this, open and carefree, rare and precious as the gems the three of you pull from the ground. Part of him wants to kiss you, but he suspects he would end up on his back in the dust with the barrel of your railgun jammed beneath his sternum, so instead he brushes his hand against yours and your fingers find his and squeeze hard.            "I've never seen one before," you say, barely aware of Ezra's hand linked with yours, "I mean, I know what a rainbow is, but I've never seen one. Not in the real, just in vids."            "They don't have rainbows on Falnost?" Says Cee.            "They don't have rain on Falnost," you say, "Get's a little hazy sometimes after the ice-haulers make a drop, but that's about it." You shake your head as if just waking, the rainbow still shimmers, a bit duller now, and you are suddenly aware of Ezra's hand clasped with yours, the gentle pressure of his grasp.             "Sorry," you drop your eyes, "I got distracted. We got work to do." Ezra gives your hand a squeeze and then lets you go.             "Not to worry, Artichoke, rainbows are fleeting things. You look your fill while you can." And so you do. So does he.

[kitzatara]

Mermay day 3: Bizarre And Cool Variations

If you’ve ever thought to yourself “is there more than just fish mermaids? Are there different kinds of fish mermaids?” Well theb congratulations. You prove that people have always been people, because we’ve been coming up with different varieties of merpeople since at least 400 BCE.

From what I can tell, Greece was the first to make more interesting variations. They created the Telchines and Ichthyocentaurs. Telchines have several descriptions but among them are dog like and mermaid like hybrids. It was said they had the heads of dogs and tails like a fish. Sometimes both and sometimes only one. They were said to know magic and were eventually cursed by the gods for using foul and evil magic. Ichthyocentaurs are so interesting to me because they are centars with a fish tail instead of hindlegs or tritons with two horse legs on their tail.

Ichthyocentaurs spawned several other similar looking mermen designs including tritons with clawed forefins on their tails, wings, and in roman times lobster and crab claws on their tails. This then spawned a crayfish triton and sonewhere in between we get two tailed tritons and tritonesses.

Inuit cultures in the far north of Canada and Greenland had a sea goddess named Sedna. Who by some accounts had a seal, orca, or whale tail. It’s hard to pinpoint when belief in Sedna began and exactly when Sedna developed mermaid iconography but she has always been closely linked with sea mammals and sea life.

In Chilé tales of the Millalobo and his merchildren who had sea lion tails were prevalent. Said to be gods and had golden hair. Pincoy was Millalobos son and his sister wife Sirena Chilota who had golden scales not too dissimilar from Suvanamaccha who was a golden tailed mermaid.

The yawkyawk of Aboriginal myth was said to have seaweed for hair. A similar aesthetic to tritons who were often described with blue skin and green hair.

One of my personal favorites is the Sazae Oni who could shapeshift into a human form. And in its demon form it had the lower half of a mollusk. Making it a very rare mermaid like creature with a shelled lower half. It has a rather wellknown story of stealing pirates balls in exchange for gold. It was also known to travel to inns and devour the innkeeper at night.

Avatea from cook islands myth was half fish on the left side as opposed to from the waist down.

Interestingly enough there doesn’t seem to be any octopus hybrids in mythology. You could maybe argue Scylla was the first tentacled hybrid but she wasn’t really depicted as half octopus and was more similar to the hydra or a dragon. Cecaelian creatures seem to be a unique creation of Disney’s little mermaid.

[dragonthunders01]

As many know well the Cambrian is the beginning of our world’s biodiversity, is an advance follow up of the ediacaran flourish of life under the ocean, the major period of life diversification with the explosion and rise of the many major clades of animals that would establish for the next 500 million years, such as mollusks, annelids, arthropods, chordates, etc. as well alongside them some other very bizarre clades that arose and at the same time perished in that span which couldn’t leave any descendant after. The marine life grew up and became more from the pacific sessile or slow filter feeders or detritivorous ediacarans stuck in the sand, radiating into a crazy mosaic of different creatures nothing like anything that appeared before and establishing the bases for the dominant clades today, with different shapes, number of legs, numbers and shape of eyes, segments, and most important… in different sizes, mostly small, but some larger than the average…

For this chart I wanted to do something more than just pick the few largest animals of period which excess the meter long (which could have been just 2 specie), so I tried to see specimen size from all other clades known from the period, giving more variety of what some of the biggest animals were, even if they weren’t gigantic like most of actual fauna, of course with this I have to be a bit selective as not many clades really became enough large, at least in this chart the species I will expose are larger than 10 cm and noticeable enough, so even the largest animals of some clades here will be out for being very, very small…

The world in this point was pretty much the world of the Panarthropods, the major clade that includes all known Arthropoda and stem-arthropod, and there is no doubt that the Lobopodians were one of the major faunistic Panarthropods in many pelagic and benthonic niches, becoming some species iconic for its many bizarre forms and some others for their extraordinary sized, specially the Anomalocarids such as the iconic genus Anomalocaris with known specimens reaching lengths of around 60 cm to a meter long making it one of the biggest predators of the ocean at the period and being the first apex predator of history; there is also a tentative competitor for the position as the biggest lobopodians, as well the biggest animal of the period, the species Omnidens amplus (originally classified as a worm), only know by a preserved set of mouthparts, which scaled up with some relatives like the benthonic dweller Pambdelurion gives a size estimation of 1.5 to 2 meters long, but for the lack of a complete body makes difficult a properly size estimation.

Alongside the Lobopodians were also the myriad species of Arthropods, most of them were in the genesis of the clades that could come up millions of years after, just like Crustaceans, Chelicerata or Mandibulata, but in this point on time these weren’t yet a thing like they would be in next periods, instead the diversity of these was formed by other clades, specially a lot of stem-group outside euarthropods and still unknown to link clades as well others euarthropods unrelated to the major clades mentioned first; the pelagic Tuzoiid Tuzoia sp. was able to reach 18 cm long, the benthonic Sidneyia inexpectans with specimens reaching up 16 cm long and  the genus Branchiocaris pretiosa which reached up sizes around 15 cm long, not giants but still pretty large among their groups.

The Trilobites are one if not the major clade of arthropods for excellence during the Paleozoic, with different variety of species, being the Cambrian the pinnacle of its population clades with more than 60 families, most of these were around the lengths of less than 10 cm and often were the prey of bigger animals, but in some others places they were able to reach a very extraordinary size, being one of the biggest species known the redlichiide Acadoparadoxides briaerus from morocco, with specimens reaching up 45 cm long. Apart of trilobites, there were some other relatives which belongs to a major clade known as “Trilobitomorpha” which resemble them in certain anatomical features, but they weren’t true trilobites, such as the Helmetiid Helmetia expansa, a very large soft-bodied looking arthropod of around 27 cm long is one of the largest non-anomalocarids arthropods of burgers shell, and the Tegopeltidae Tegopelte gigas with a size of 19 cm.

The Archaeopriapulida (stem-priapulids) were other of the predatory benthonic animals of the Cambrian landscape, pretty much found burrowing in the sand and mud and protruding from their places, exposing a large proboscis they were mostly ambush hunters. The most well known is probably Ottoia for the common of its specimens, but these often doesn’t pass the length of 8 to 15 cm, but others were bigger that this one, a good example is the species Louisella pedunculata, which the largest specimen reached a size of 30 cm long with the proboscis extended.

One odd group among the Cambrian biota was the Vetulicolians, an enigmatic clade probably related to deuterostomes. These were weird arthropod-looking creatures that shown adaptations for pelagic lifestyle and mostly being filter feeders, many of these tended to be average lengths less than 10 cm, but Yuyuanozoon magnificissimi from comes to be the largest species known, with a length of 20.2 cm

The Chordates diversity during the Cambrian was formed by a small group of vermin agnatha forms, mostly swimming filter feeding of small size of few centimeters, the largest of these was Metaspriggina with specimens reaching up to 10 cm long which wasn’t that large size compared to many Cambrian lifeforms, was still an outstanding length compared to other of the chordates of the period.

Echinoderms were in their early genesis of its diversification with some unique morphology, so bizarre and alien compared to our actual species, as well there were others similar or very close in many aspect to actual ones, although most were very minuscule, some of the few macroscopic forms included, Lyracystis which is the largest eocrinoid with specimens reaching up sizes to 21 cm tall being half of it the arms.

Lophotrochozoa flourished during this period, evolving into the important clades including the very common brachiopods, the basic annelids and the Mollusks, although there were some species that could be classified as the last ancestors or stem-relatives of such clades, they don’t belong to these clades but they are coming to the roots of these, including Odontogriphus which specimens were able to reach up sizes around 12 cm long. Mollusks started their slow path into diversification with early small shelled varieties, most of them minuscule and don’t reaching up few centimeters of length, although few reached some considerable size for the average, such as the pelagic Nectocaris pteryx, the enigmatic cephalopod-like mollusk (?) with specimens reaching up sizes of 7 cm long.

Cnidaria are among the oldest animals on earth which during the cambrian expanded though the warm oceans either as jellyfish or small coral-like forms that could spread in the next periods, among some of these early species there was Echmatocrinus  which is a pretty robust form with a height of 18 cm tall.

Sponges were one of the major reef builders of the Cambrian, forming alongside other sessile lifeforms extensive biomes which thrived in the warm swallow oceans. Some of the biggest sponges found so far belong to the species Quadrolaminiella diagonalis which were barrel shaped sponge from the Chengjiang Fauna, with a height of 20 cm and a diameter of around 12 cm. Another species was Leptomitus, a very tall but thin kind of sponge from Burgers Shale, with specimens reaching up heights around 36.4 cm, but with a diameter less than a centimeter long.

A minor stuff worth to mention, other of the bizarre benthonic reef builders that dominated the Cambrian seabed were the archaeocyathids, a group formed by small conical shaped forms with some brachiating forms, similar in many ways to sponges except in inner structure, some of these often reached sizes of around 9 to 10 cm tall and some centimeters in diameter, but according to some mentions in websites and papers some were able to reach up even very larger sizes, with giant specimens reaching around 60 cm, but I wasn’t able upon this date to locate these very big forms so I couldn’t add them (either these are exaggerated estimations from fragmentary individuals or actually those were hinted from other fossil sponges)

References

-Briggs, D. E. (1972). Anomalocaris, the largest known Cambrian arthropod. Palaeontology, 22(3), 631-664.

-Vinther, J., Porras, L., Young, F. J., Budd, G. E., & Edgecombe, G. D. (2016). The mouth apparatus of the Cambrian gilled lobopodian Pambdelurion whittingtoni. Palaeontology, 59(6), 841-849.

- Xianguang, H., Bergström, J., & Jie, Y. (2006). Distinguishing anomalocaridids from arthropods and priapulids. Geological Journal, 41(3‐4), 259-269.

-Whittington, H. B. (1985). Tegopelte gigas, a second soft-bodied trilobite from the Burgess Shale, Middle Cambrian, British Columbia. Journal of Paleontology, 1251-1274.

-Bruton, D. L. (1981). The arthropod Sidneyia inexpectans, Middle Cambrian, Burgess Shale, British Columbia. Philosophical Transactions of the Royal Society of London. B, Biological Sciences, 295(1079), 619-653.

­-Vannier, J., Caron, J. B., Yuan, J. L., Briggs, D. E., Collins, D., Zhao, Y. L., & Zhu, M. Y. (2007). Tuzoia: morphology and lifestyle of a large bivalved arthropod of the Cambrian seas. Journal of Paleontology, 81(3), 445-471.

- Rudkin, D. M., Young, G. A., Elias, R. J., & Dobrzanski, E. P. (2003). The world's biggest trilobite—Isotelus rex new species from the Upper Ordovician of northern Manitoba, Canada. Journal of Paleontology, 77(1), 99-112.

- Daley, A. C., Antcliffe, J. B., Drage, H. B., & Pates, S. (2018). Early fossil record of Euarthropoda and the Cambrian Explosion. Proceedings of the National Academy of Sciences, 115(21), 5323-5331.

- Aria, C., & Caron, J.-B. (2017). Burgess Shale fossils illustrate the origin of the mandibulate body plan. Nature, 545(7652), 89–92.

-Walcott, C. D. (1911). Cambrian Geology and Paleontology II: No. 5--Middle Cambrian Annelids.

-Morris, S. C., & Caron, J. B. (2014). A primitive fish from the Cambrian of North America. Nature, 512(7515), 419.

-Sprinkle, J., & Collins, D. (2006). New eocrinoids from the Burgess Shale, southern British Columbia, Canada, and the Spence Shale, northern Utah, USA. Canadian Journal of Earth Sciences, 43(3), 303-322.

- Sprinkle, J., & Collins, D. (1998). Revision of Echmatocrinus from the middle cambrian burgess shale of British Columbia. Lethaia, 31(4), 269-282.

- Caron, J. B., Scheltema, A., Schander, C., & Rudkin, D. (2006). A soft-bodied mollusc with radula from the Middle Cambrian Burgess Shale. Nature, 442(7099), 159.

- Walcott, C. D. (1917). Middle Cambrian Spongiae. Smithsonian Miscellaneous Collections.

- Legg, D. A., Sutton, M. D., & Edgecombe, G. D. (2013). Arthropod fossil data increase congruence of morphological and molecular phylogenies. Nature communications, 4, 2485.

- Wu, W., Zhu, M., & Steiner, M. (2014). Composition and tiering of the Cambrian sponge communities. Palaeogeography, Palaeoclimatology, Palaeoecology, 398, 86-96.

[chatnoirismycinnamonroll]

Hey so I'm somewhat new to the Miraculous Ladybug fandom, and was wondering if you could suggest some good fanfics for me? Also I was wondering, I've seen this character called Felix in some of them and I don't know where he came from?

Oh, welcome to the fandom! There's so many fics I wish I could recommend, but I'm on mobile and have no idea how to link things, I'm sorry.

However, I can lead you to several authors here on Tumblr that you can follow that have created many great stories:

@gale-of-the-nomads : I highly recommend their Soulmate Survey AU, which is mostly pure fluff and focuses on reviving the fandom with their love for Adrienette.

@zoe-oneesama : they have an ongoing comic focused on their AU called the Scarlet Lady AU, which focuses on the idea of Chloe Bourgeois having, somehow, gotten thr Ladybug Miraculous instead of Marinette. This AU is what actually got me into the fandom, and they update mostly Wednesdays and Saturdays. Highly recommend.

@nobodyfamousposts : They have several aus as well, but the one I remember most right now would have to be the Dolls AU, where Marinette somehow has creation magic, and every doll she makes somehow comes to life. These dolls see her as their mother, and they love and protect her, especially her little Chaton. Check it out, it's pure fluff.

@ozmav @maribat-archive : they are creating content for a recent AU in which, due to a certain episode in canon that almost everybody in the fandom hates called Chameleon, Marinette is shipped with Damian Wayne after she and her class go on a field trip to Gotham to visit Wayne Enterprises. It is not Adrien, Lila, or the class friendly, but it does explore a sweet dynamic between Marinette and DCs Damian Wayne, or Robin.

@miraculously-quality-content : check out their OctoDad AU, which consists of Original Characters that explore the idea of the heroes having an actual guide in both their civilian and hero lives. With the Octopus Miraculous, the adult hero Mollusk helps the heroes battle both Hawkmoth and the challenges of life. Basically: Mollusk is a cinnamon roll that can kill you if you hurt his kids.

Here are some others that have some great AUs or just some little ficlets that are very entertaining: @lunian @ladybub @mari-cheres @miraculouscontent @miraculous-of-salt

Now, for Felix. I dont really know much either, but I do know some things, not sure if they're right tho: Felix was a character created by Thomas Astruc in the early stages of Miraculous Ladybug, which we call the PV version. It was designed as an Anime, but they later changed the company to ZAG, which designed it as we know it now.

Felix was cold, distant, and almost emotionless. He didnt want to be Chat Noir, but was cursed with bad luck, and became Chat Noir. The only way to get the curse off was to get a kiss from his partner, Ladybug, who definitely does not want to kiss him. The love square is still in effect, but more snubbing from both sides. Felix doesnt want anything to do with Bridgette, the PV Ladybug, and Ladybug doesnt want anything to do with Chat Noir. But he helps her defend Paris, so she "deals" with him. It was never completed, or even expanded on much, but the fandom really liked Felix, since he wasnt "perfect" like Adrien is made out to be.

Now, the fandom loves Felix more on the basis of "what could have been", and some fanfiction writers really took the charcater and adapted him into a more likeable character, especially after the episode Chameleon which, if you've watched it, you can find many fics and headcanons that "fix" this episode under the tag #mlsalt.

Felix also made a comeback in the fandom after someone leaked the episode names for Season 3, and we saw an Episode that revolves around Felix. The reason why is because Astruc himself had said that Felix was never going to show up in Miraculous ever again, as Astruc absolutely hated his character, but seeing an episode revolving around Felix coming up made the fandom question why? Why did Astruc lie? What is he going to do with Felix? Is he going to make Felix look worse? The fandom isnt having it so far, and had started to create content revolving around Felix and his involvement in the class, and his relationship with Marinette.

@miraculous-of-salt really made me like Felix as a love interest to Marinette in her God AU, in which Marinette is Persephone, the Goddess of Life, and Felix is Hades, the God of the Underworld, or Death.

There are so many fanfics and headcanons and ideas, that I really cant tell you how many I have seen. I've literally only been here 1 year, and I've already seen so much. Each episode that comes out helps us to create more content for our fanfictions, and with Lila Rossi reentering the picture this season, most fanfictions have her as the main antagonist, apart from Hawkmoth, as she is now seen as a greater evil.

You can also check out @ao3feed-ladynoir for more ML fanfiction. They almost regularly post new Fanfiction links to AO3, and they cover almost everything.

I hope this helps you in getting into the fandom further, and if anyone else wants to add more writers or fanfictions to check out, please be my guest and reblog with your info. Let's help someone out, shall we?

Oh, also @buggachat Cant believe I almost forget them.

[knifeshoeoreofight]

Part 1  Part 2  Part 3

Finding S and Magda is easy after that. The process almost becomes routine, if teaching ASL to a fairytale could ever be considered routine. They pack up, and head out to where Magda’s tag was last pinged. S usually finds them after that. 

Zhenya knows that there’s an expiration date on this, that eventually, when her calf is strong enough, Magda will have to swim north to her feeding grounds. She, like other humpback mothers, will barely eat the entire time she’s in tropical waters raising her baby. She needs to get back to the food-rich northern waters or she’ll starve. 

Zhenya doesn’t know what Sid will do then, or what Zhenya’s going to do, for that matter. He tries not to think too much about it, or about all the research he’s not doing, the funding that’s steadily running out. One day at a time, he tells himself. No one’s ever had an opportunity like this before. He has to make the most of it.

S’s vocabulary continues to expand. Geno scrambles to keep up, googling language learning theory late into the night, feverishly combing YouTube for ASL instruction videos.

They’re currently working on colors. Geno doesn’t even know how S sees color, but he does learn a lot when he tries to teach S the sign for “blue.”

Word? S asks, pointing at the blue stripe painted around the boat.

Blue, Zhenya tells him.

S points at the water around them.

Blue, Zhenya repeats. S makes a “wow, okay, no” kind of face. He points at the sky.

Blue, Zhenya says again. S rolls his eyes. He starts pointing at blue things and making a different sound for each. So Geno has to teach him a few modifiers before he’s content: “gray,” and “green,” and “light” and “dark.” It makes sense, Zhenya figures. These are the colors that make up the greater part of S’s world.

S remains dissatisfied with the limited human expression of color, but his fascination with humans themselves doesn’t abate. He shows a marked preference for interacting with Geno, but seems to like Letang and Fleury well enough, especially Fleury. Fleury is the one who decides that they can’t keep calling him “S.” He runs a whole gamut of names starting with “s” past him, and S makes faces at them all, until Fleury tries out “Sid.” That one is met with a shrug and a thumbs up, so “Sid” he becomes.

Sid brings them a fish one day, a beautiful yellowfin tuna, easily a meter long. He heaves it onto the dive platform with pride, then pats its glistening, iridescent side.

E, he says. You like.

Zhenya blinks. Yesterday had included a long conversation on food likes and dislikes, Zhenya talking to Sid while Letang scribbled down data on merpeople’s dietary habits and Fleury googled frantically to try and identify the species Sid was talking about.

Zhenya, for reasons he’s not. Thinking. About. feels his face flush a little. “Yes,” he says and signs at the same time. “I like fish.”

This one. Good? Sid asks.

“Very good. Best.”

“Awww, Geno got a present,” Fleury laughs. “What about me, Sid?” Fish for Flower? He asks, using the sign he’s chosen for himself.

You eat fins, head, Sid tells him, smirking. He looks back to Zhenya, smirk softening. He pats the fish again and looks encouragingly at him.

Oh no, Zhenya realizes. He’s waiting for Zhenya to try it. Right here. On the boat. Raw. Zhenya’s a big sushi fan but there’s a difference between a pretty, delicate slice of sashimi and a whole massive fucking fish, lying bleeding at your feet while a hopeful looking merman blinks up at you, waiting for you to tuck in, apparently.

“Give me my dive knife,” he sighs at Fleury, and with some difficulty, manages to hack off a piece of the yellowfin. Sid watches intently as Zhenya takes a bite.

It’s fresher than the best sushi he’s ever eaten, and it’s actually, gory acquisition aside, kind of incredible. “Wow,” he says. “It’s delicious.” He makes the sign for Sid.

Delicious is very good, for food, he tells him.

I’m happy, Sid tells him. Eat more?

And that’s how Zhenya ends up sitting with his feet in the ocean, hacking pieces of raw tuna off its carcass and sharing them with a merman. And eventually Letang and Fleury, once he convinces Sid to share. He grins at nothing in particular, and wonders how this is his life.

The tuna opens the floodgates, apparently. Sid starts bringing him things. One day it’s a smooth, fist-sized cowrie shell, another it’s a enormous living conch. Zhenya thanks him for that one, puts it in a cooler full of seawater, and sets the cumbersome mollusk free once they’re back to the shallows. The handful of pretty calico scallop shells he receives a few days later, he keeps.

Sid kept some for himself as well, and spends an afternoon deftly knotting them into a sort of necklace using strands from one of their ropes that he cajoles Zhenya into giving him.

No shells these north, S tells them, tying the necklace around his neck and looking pleased with himself. His syntax gets a little creative sometimes.

“Very pretty,” Zhenya signs and tells him. At Sid’s confused look he explains. “Pretty is ‘good,’ for your eyes.”

“Beautiful is very pretty,” Letang helpfully supplies. Sid nods, taking it all in.

When Letang and Fleury are occupied with something else, Sid looks at the movement of Zhenya’s hands as he signs and tells him: your words are beautiful.

Zhenya’s heart thuds painfully. “Word?” he says out loud, hands stilling in surprise.

No, Sid says, and reaches out to tap a finger on the back of Zhenya’s hand. These.

“Oh,” Zhenya says out loud, and suddenly he can’t look at Sid, his chest tight and aching. Sid trills softly in concern, until Zhenya looks up at him.

E? You good? He asks. Zhenya can only swallow, and nod.

Sid’s sitting on the dive platform as he often does, and Zhenya’s suddenly aware of how close they are.

Pretty? Sid asks, and Zhenya nearly dies before he sees Sid follow the question with a touch to his new necklace.

Yes, he replies.

Beautiful, Sid says, reaching out to touch the gold chain Zhenya always wears, looking ever so slightly wistful.

Recklessly, Geno unclasps his chain, letting the gold links slither into his palm. Feeling foolish and helpless, he holds it out to Sid.

Sid’s eyes go wide, and he reaches out to take the chain carefully, gaze a little disbelieving. He lets the chain slide through his fingers, and holds it up to watch the sun wink off of it.

“Here,” Zhenya says, his voice rough. He take it, and lays it around Sid’s neck, doing up the clasp in the back. He runs a finger down it, straightening out the kinks. Sid is making a soft hum in his throat, and his eyes are big and dark. He looks down at the chain shining against his skin, and touches it. Zhenya wants to give him a dozen necklaces, drape him in gold, just to see that soft look of wonder in his eyes again.

Sid reaches up and unties the shell necklace from around his neck, and before Zhenya can move, he’s leaning in close to tie it around Zhenya’s. Zhenya can feel the warmth of his skin, can see the kaleidoscope of color in his eyes. A bead of water slides from his drying hair down his cheek, to the corner of his full, perfect lips.  

What the hell is Zhenya doing. What the hell is he allowing himself to feel? He should, if he had any integrity or sense, stop this. Shut down...whatever this is. God, Sid’s not even the same species as he is.

Instead he looks at the soft, pleased smile on Sid’s face, and feels powerless to do anything that would chase it away.

Fleury takes a long look at the shells around Zhenya’s neck during their boat ride back to the marina.

“You should be careful, man. It’s like...I don’t know. All these presents he brings you. You don’t know what they mean in his culture. And now you gave him something back. For all you know, that’s like, getting engaged or something.” Zhenya’s cheeks go flame-hot.

“Don’t be stupid,” He tells Fleury, but inside he think that he’s the stupid one here, probably.

***

He dreams of Sid that night. Dreams about running into him on the street, dreams about him walking up to Zhenya with that smile of his. On two legs and two feet. He dreams that he speaks to him in Russian.

“You like me, don’t you?” Dream-Sid says, with an accent so perfect he sounds like he was born a street away from Zhenya. “You like me.”

Dream-Zhenya opens his mouth and tries to say something back, to protest,  but all that comes out is a series of trills and clicks, like the sounds real Sid makes.

“Oh,” Dream Sid says, face slowly going terrible and cold. 

“I don’t understand you. I don’t know what you’re trying to say.”

[downtoearthmarkets]

Scallops … one of the sea’s greatest gifts. Found in saltwater (like the Atlantic Ocean), scallops are bivalved mollusks that live inside a hinged shell and can be found around the world. Unlike oysters, mussels, and clams, scallops are free-swimming. What most people recognize as a "scallop" is the creature's adductor muscle, which it uses to clap its shells quickly, forcing a jet of water past the shell hinge, propelling the scallop forward. They're surprisingly speedy. Atlantic sea scallops can have very large shells, up to 9 inches in length. Bay scallops are smaller, growing to about 4 inches. The gender of Atlantic sea scallops can be distinguished. The females' reproductive organs are red while the males' are white. Scallops are widely considered one of the healthiest seafoods. Made up of 80% protein and sporting a low-fat content, they can help you feel fuller longer and are rich in vitamins and minerals. They are also a great source of antioxidants, which can help protect your body against cell damage linked with a range of chronic diseases. Here are some other amazing scallop facts that you probably didn’t know:

Scallops have anywhere up to 200 eyes that line their mantle. These eyes may be a brilliant blue color, and they allow the scallop to detect light, dark, and motion. They use their retinas to focus light, a job the cornea does in human eyes.

Like a tree, each ring on a scallop’s shell represents a year of growth, although a ring might also record a stressful incident in the scallop’s life.

The scallop is the only bivalve mollusk that can “jump” and “swim”.

There are more than 400 species of scallops found around the world.

Scallops are one of the cleanest shellfish available. The abductor muscle is not used to filter water, so scallops are not susceptible to toxins or contaminants the way that clams and mussels are.

The lifespans of some scallops have been known to extend over 20 years.

Like all bivalves, scallops lack actual brains. Instead, they have a well-developed nervous system.

Be sure to check out your farmers’ market fish vendor this weekend for a variety of fresh and locally caught fish.

[hippo-euphoria]

Random Assortment of Marine Biology for the Writer - Shark Edition

this past year i took aquatic science, which basically combined oceanography with marine biology while also throwing in a healthy dose of chemistry and physics- 10/10  would take again.

anyway i easily learned more from this class than any other in the past, and i’ve been steadily drawing from this information in my writing, so why not make a list? because there’s like, no way in hell i could fit everything i learned into one post, i’m gonna break it down a bit, beginning with:

SHARKS

- phylum chordata

- sub-phylum - craniata 

skulls and spines mean central nervous system (CNS) and a brain

- class chrondrichthyes 

cartilaginous fish, i.e. skeleton made of cartilage, also including skates and rays

cartilage - flexible connective tissue made of cells/protein

- characteristics

placoid scales/dermal denticles (literally meaning skin teeth), embedded in the skin, smooth one way and sandpaper-like the other, it’s possible to nick your hand on these

5-7 visible gill slits

spiracles behind each eye, passes water over gills

wing-like pectoral fins, grant lift when gliding through the water

source

- structure/behavior, or in other words, epic adaptations we don’t have

lateral line, nerve line going down the side of the body, many nerve endings, detect vibrations in the water

epic sense of smell, can detect blood a half-mile away

ampullae of lorenzini - pores on their noses, look like black heads, are not black heads, instead detect electrical fields made by the movement of other sea life, i.e. shark food

replaceable teeth, but we all knew that, but also their teeth/jaws are the only pieces we actually find fossilized, because the cartilage is eaten/broken down

continuous swimming, NOT BECAUSE THEY NEED TO SWIM TO BREATH but to stay floating and not sink- more on that later

eye-nictitating membrane - covers eye to protect it while feeding, because sharks are messy eaters

source

source

- reproduction

internal fertilization, meaning they actually do the sex, or as it was explained to me, “they evolved the ability to actually do it”, which is kinda significant in the fish world

males have claspers, tiny fins behind pelvic fins which transfer sperm

there are actually three ways sharks can make babies, it’s wild

oviparity - (ovi=egg), actually lay eggs - horn shark, cat shark, Port Jackson shark etc.

viviparity - (vivi=living), live birth, placental link to young, like mammals - hammerheads shark, basking shark, dogfish shark

ovoviviparity - (egg, living), probably one of the most metal birth processes, the eggs stay inside the female, they hatch, they feed off the remaining yolk/fluids, but in some species the first to hatch eat the remaining eggs/embryos, then they’re born -  it’s a fight to the death to even live, all inside the mother

- fun facts bro

dogfish have the longest gestation period of any shark - 18-24 months, meaning the females can be preggers for up to two years

not all sharks have all the fins, a complete list of fins: pectoral, 1st dorsal, 2nd dorsal, pelvic, anal, and caudal

generally the only sharks that will attack people are tiger sharks and bull sharks because they’re just mean as hell, or in other words they have a lot of testosterone, or in other other words they’re the football team at a frat party

sharks don’t like the taste of people, they bite and let go when they realize their mistakes

except for bulls and tigers, as aforementioned 

really, they probably won’t kill you, just bite you a little and let go, you’ll be fine

sharks have huge livers which can make up like 40% of their body weight, they don’t have swim bladders, so all the liver oil is what makes them buoyant, but oil is heavier than water, so if they don’t swim they sink - THEY DO NOT NEED TO SWIM TO BREATHE, the spiracles pump water over the gills when they’re still

now if you’ve made it this far you get a cool bit of info about an extinct shark with a weird looking jaw that we’ve found this fossil of:

source

weird right? so we’ve got two guesses of what this could’ve looked like:

source

source

now this thing is being referred to as the helicoprion shark, and it went extinct forever ago so you have nothing to fear - and any images you see of this guy are fake or scientific renderings

next awesome fact, off the coast of Africa great whites actually leap out of the water, and you’ve probably already seen pictures so i won’t bother inserting any

that’s the end of the sharks, probably, i hope i learned you a thing or two, tune in next time when i talk about mollusks, and maybe the source of my favorite conversation starter, barnacles

[evolutionsvoid]

The Lou Carcolh, or also known as Snail Dragons, are another prime example of how "dragons" are not an actual official family of creatures. As I have stated in previous entries, the term "dragon" is used for labeling or describing large, intimidating creatures that terrify locals and cause issues. The species that are indeed giant, reptilian monsters are referred to as "true dragons," as the regular dragons can refer to a conglomerate of species that vary wildly in anatomy, class and many other things. Grinning Dragons, Bone Dragons, Arctic Dragons and Snail Dragons all carry the label "dragon," but are so incredibly different from one another that even trying to link them together is silly. I mean, just in those four is a mollusk, a reptile, an insect and a mammal. Quite different indeed! Anyways, I bring this up because this entry is about the Lou Carcolh, which many like to call Snail Dragons. The Lou Carcolh live in temperate climates, setting up their homes in caves, tunnels, crevasses and other rocky structures. They are solitary creatures, only coming together during mating season. A Lou Carcolh prefers rocky terrain and a place that is either damp or receives a decent amount of rain. As a species, the Lou Carcolh do not need much to get by. They do not require a complex nest, nor a massive territory for hunting. Instead, they like to find a nice, rocky place to hide and then wait there for prey to come by. 

These large mollusks are ambush predators, catching prey that walk by their dens. When they wish to hunt, a Lou Carcolh will slowly crawl its way to a hidden spot. Some hide in the darkness in caves, some cling to sides of cliffs and crevasses, while some may even bury themselves in vegetation to hide their mass. Once properly hidden, they will snake their extremely long tendrils out into the open, hiding them in the foliage or blending them in with the rock around them. They will set their trap on trails and other places that show sign of activity and passage. There, their tangled net will lay, waiting for some poor sap to come trundling by. When prey steps amongst their tendrils, they will rise up and snare the creature in their sticky embrace. The tentacles of a Lou Carcolh have a natural adhesive and stiff hairs that allow them to trap smaller prey or properly hold larger, thrashing animals. When a victim is tangled in their grip, the Lou Carcolh will reel them back into their hiding place. The tendrils will bring them to their mouth, where they will inject them with paralyzing venom from their fangs. When prey is immobilized, the Lou Carcolh will seize them in their mouths and begin the slow process of feeding. Lacking powerful jaws for cutting and chewing, the Snail Dragons instead use a saw-toothed radula that takes up their entire lower jaw to slowly rasp away flesh. The backwards facing teeth help keep the victim in place and tear away at them as the Lou Carcolh works its jaw back and forth. Needless to say, being eaten by a Lou Carcolh is a long and painful process, as the victim is usually still alive. The venom only paralyzes your muscles, so it does not kill you instantly. Death will only come through asphyxiation or blood loss, and neither are all that great. The Lou Carcolh will continue to rasp away at its prey until it has broken down enough of them to swallow whole. After prey is consumed, they shall rest and digest for some time, before setting out their trap again. The trapping tendrils of a Lou Carcolh also aid in getting water, as there are small vessels that run throughout the tentacle. When thirsty, they will send their tendrils out to find puddles and pools. The appendages will submerge themselves and siphon water to the main body far away. That way Snail Dragons don't need to go out in the open to get a drink! Due to their large size and slow lifestyle, the Lou Carcolh can live for quite a long time. Some stories have claimed that certain specimens have been centuries old, growing to a size and strength that is impossible to slay. I have heard some tales that there are a few mountains out there that are notorious for causing travelers and climbers to vanish. They believe that a massive Lou Carcolh lives within the rock, sending out mile long tendrils to catch any who are foolish enough to climb its peak. Some even say that the mountain itself is there shell!   When it comes to reproduction, Snail Dragons are a bit different compared to other "dragons." The Lou Carcolh are hermaphroditic, possessing reproductive organs of each gender. This works to their advantage, as these creatures are quite slow when it comes to travel. When mating season occurs, the Lou Carcolh travel to find pheromone trails left by others in hopes of finding a mate. Since they are slow, this searching can take weeks until they find another of their kind. With that, you don't want the issue where you put all this time and effort only to find that you have tracked down an incompatible mate. Being hermaphrodites, any individual they find can do the job! So when two Snail Dragons come together, they do their courtship and then one (or both) of them fires a "love dart" into the other. These hardened, sharp "darts" are filled with sperm, and are how one Lou Carcolh fertilizes the other. They are located in the same region where the fangs are, developing prior to the mating season. When the time comes, the two shall do their dance and try to strike the other with this "dart." Whoever winds up getting embedded with this structure will be fertilized, allowing them to bear and lay eggs. In some cases, both wind up getting darted, so they both play the egg-laying role. Once the ritual is over, they part ways and head back to their hunting ground. The eggs will be laid beneath the soil and abandoned. The young that hatch will have to fend for themselves. Due to their large size and odd appearance, the Lou Carcolh are quite famous creatures to the locals. Certain rocky formations are named after them, especially if they look like a snail shell. There is a local vine that is called "carcolh tongue" due to its hairy, wandering tendrils that lay upon the ground. They are usually one of the first suspected when someone goes out to rocky areas and vanish, and many warn one another that "the carcolh will catch you!" The origins of the Lou Carcolh is also a popular tale in the region. The story goes that there was a time, long ago, when the dragons ruled the skies. The massive beasts were so plentiful, that they would blot out the sun for days on end. After years of darkness and destruction, one man decided to finally bring the monsters down. He donned his armor and crafted a great, mighty bow. With arrows the size of lances, he shot the dragons from the sky, causing them to plummet from the sky and splatter amongst the rocks. The dragons tried to slay him, but his abilities with his bow could not be beaten. Others took up weapons like his and they worked to clear the skies of these large creatures. During this massacre, there was a group of dragons who brought themselves to the ground, terrified of the lethal arrows. Seeking to avoid their own demise, they tore the wings from their backs and bound themselves forever to the earth. In time, they slowly became the Lou Carcolh, hiding in caves in fear of this mythical warrior. It is a fun story, but one that carries the same cliche every human tale has. For some reason, humans really like to act like they are the creators or cause of every living thing in this world. Every origin story centers around their actions. It's kind of weird. It's like how there are a large chunk of people out there that think that all of dryad kind was created by a lonely Mycomancer! It's ridiculous! (And it's also a tale I would not read to your saplings, because YIKES!)   Another thing that makes the Lou Carcolh infamous to the region is their "love darts." The large stinger-like reproductive organs are things people have a hard time understanding, and they also create some bizarre scenarios. There was a time, a while back, when people thought that the Lou Carcolh abducted virgins and used their "love darts" to impregnate them with their larvae (That is also another thing that shows up in a lot of human tales: monsters doing naughty things to others. Makes you wonder who comes up with this stuff.). It was also seen as the ultimate sign of humiliation for those who hunted the Carcolh. Since the "love dart" is situated in the mouth, those who get near its fangs or struggle in its grip may accidentally set it off. It has been said that those warriors who have accidentally been shot with this dart during battles usually wander off into the woods, never to be seen again. They apparently were too ashamed to show their faces ever again. The other thing their "love darts" are famous for is outsiders not realizing what they are. Days after the mating process, the "love darts" are pushed out of the body and discarded on the ground. Travelers have stumbled across these strange things and see them as potential weapons. They are barbed, dagger-sized and lightweight, so a little modification would turn them into a decent knife. These travelers would then show up in town and show off their new blade, which would cause every citizen to nearly die of laughter. The terms and names they call these people who wield them are not appropriate, and I cannot write them in here but trust me when I say they are quite colorful and descriptive. It has become a gag for certain locals to craft weapons out of "love darts" and sell them to ignorant travelers, so that they can chuckle behind their backs. They just love the idea of oblivious people walking around with these, thinking they are legitimate weapons and unaware of their origin. Funny enough, I actually do own one of these dart-knives, but I was aware of it when I bought it. I have always thought they were quite interesting and I always wanted to own one. In order to avoid the embarrassment, I told the man who was selling them that I knew what they were but wanted to buy one regardless. I told him that I had "always wanted one" in which he replied to me with a "oh yeah I bet you do," which resulted in a broken nose and a free knife. Despite the comments during the purchasing process, I quite like the blade and it is quite nifty. Though I must warn those who ever think of owning one, make sure you pay attention to which knife you are using for any task you do. When I was staying with some colleagues one time and it was my turn to serve dinner. When it came to cutting up the roasted chicken, I used the knife I had on hand to carve. It took me a second to realize why they were looking at me with such disgusted, horrified looks. Needless to say, no one ate the chicken that night. Chlora Myron Dryad Natural Historian ------------------------------------------------------------ A mythical creature that is a fusion of a snail and a snake?! Where has that been all my life?!     And yowzas that last paragraph was not intended when I first started writing this, but it was way too funny for me to pass up. Sorry there, folks.

[deep-sea-scholar]

The Walrus Whale

(Above: Male Odobenocetops skull exhibiting sexually dimorphic canine)

With the KT extinction event, and the linked decline in numerous reptile families, multiple environmental niches were opened to other chordate families.  Of these the marine environment was perhaps the most opened for expansion.  Today the only true marine reptiles are the salt water crocodile, Crocodylus porosus, the Squamata subfamily Hydrophiinae (sea snakes), the Testudines superfamily Chelonioidea (sea turtles), and the marine iguana, Amblyrhnchus cristatus. In their stead, mammals have risen to prominence by adapting to multiple climates and environments.  By far the most impressive of these mammalian adaptors have been the cetaceans.  While some evolved into the modern Mysticetes, and the rest into the Odontocetes, one group diverged from the dolphin superfamily to create one of the most specialized cetaceans known to science.  The nicknamed walrus whale, Odobenocetops leptodon, the only known cetacean exclusively adapted for bottom feeding.

The name Odobenocetops is a mixture of Latin and Greek nomenclature.  It breaks down into the Greek words odon, “tooth”, baino, “walk”, and the Latin words cetus, “whale”, and ops, “like”.  Loosely translated it means, “whale that seems to walk on its teeth.”  The species was extant during the middle Pliocene (5.3-3.6 m.y ago) along the coast of what is now modern day Peru and Chile. It was first described by Christian de Muizon in 1993, with the excavated skulls and assorted bones suggesting that the mammal grew to around 2.1 meters in length, and weighed in at around 150 to 650 kg.   Muizon found the species remarkable as “O. leptodon defied the evolutionary Odontocete pattern, by having a rostrum (snout) that is sharply angled downwards and a nasal opening that is drifting back towards the tip of the snout.” [Muizon, C. (2002)].” In addition, the extinct chordate exhibited two rear facing tusks, with the one on the right growing to three times the size as the one on the left in male specimens, giving it its nickname as the “walrus whale.”

Despite a remarkable resemblance to the walrus, detailed analysis of the fossils reveal that the mammal was definitively a Cetacean.  It possessed an immobile elbow joint, as revealed by a recovered fossil forelimb. Its skull lacked a true cribriform plate, which separates the nares in other mammal skulls, and instead had a group of foramina that allowed the passage of olfactory nerves to the olfactory lobe.  The frontal bone of the skull possessed a large supraorbital process that overhung the eye.  It possessed large air sinuses in the auditory region of its skull, connecting to enlarged pterygoid sinuses in the palate.  And the narial fossae (breathing passages) were located dorsally, though not as far back as in modern cetaceans.

(Above: Artistic reconstruction of the extinct cetacean)

Although there is a significant anatomical and evolutionary distance from the modern walrus, Odobenus rosmarus, the similarly tusked Pinneped is perhaps one of the best analogs to the theoretical behavior of the extinct cetacean.  Walruses have three uses for their elongated canines. Firstly, during winter they aid in opening and maintaining holes in the ice, an unlikely usage for Odobenocetops tusks due to their warmer, eastern pacific range.  Secondly, they help to stabilize the walrus as they flush benthic mollusks out of marine sediment.  A behavior that is defined in the Odobenocetops nomenclature, and suggested by similarities between the feeding structures of both walrus and Odobenocetops skulls, both having curved gripping mandibles and oversized buccal cavities capable of sucking soft bodied mollusks from their shells. Lastly, in social groups, males utilize them for dominance displays, with the males possessing the largest and strongest tusks typically dominating the herd. 

(Above: Walrus flushing marine sediment to locate mollusks)

Dominance displays involving exaggerated canines are readily observed in the modern Ondontocetes that possess them.  Beaked whales, such as Blainsville’s beaked whale and Cuvier’s beaked whale, are covered in long thin scars from male dominance displays involving their protruding canines. Bull narwhals rub tusks in a behavior known as tusking, where they establish hierarchy in social groups.

Bottom feeding is similarly not limited to Pinnipeds. The gray whale, Eschrichtius robustus, has been commonly observed forcing its jaw through sea floor sediment and straining the mud through its baleen to capture invertebrates.  The Humpback Whale, Megaptera novaeangliae, scrapes its jaw along the seafloor to scatter sand lances out of the sediment and towards the surface, where the rorqual can ensnare shoals in a bubble net and consume literal tons in a single lunge feed.  And the narwhal, the closest cetacean physiologically to the Odobenocetops, feeds on bottom dwelling halibut and other flat fish during the Arctic winter.

(Above: Bottom feeding grey whale)

The narwhal, Monodon monoceros, and the closely related beluga, Delphinapterus leucas, are considered to be the closest living relatives of Odobenocetops. Like the Odobenocetops they have flexible necks. In fact, they possess the only examples of flexible necks in living cetaceans.  This is due to jointed (as opposed to fused) cervical vertebrae. The Odobenocetops had similar unfused cervical vertebrae, creating a 90 degree range of motion for its head and allowing it to maneuver its tusks.  A similar behavior is observable in modern narwhals, which use their flexible necks in conjunction with their elongated canines to stun Arctic cod in flicking motions.  The rostrums of the beluga and narwhal are reduced, although their skulls are designed to support melons which enable echolocation, which the extinct cetacean lacked.  Also similar to Odobenocetops, the narwhal has evolved so that it possesses a pair of asymmetrical exaggerated canines, though they are not sexually dimorphic like Odobenocetops.  In most narwhals, the left canine curls into a tusk that extends through the upper lip up to a length of eight feet, while the other adapted canine rarely protrudes past the skull.  There have been occasions where both tusks have developed fully, with a higher percentage of these instances occurring in females.

(Above: Unfused beluga cervical vertebrae)

What we observe in the Odobenocetops is the product of a fascinating evolutionary path that led to a bottom feeding cetacean, and left behind two of the most unique of the modern toothed whales.  While transitionary fossils between this unconventional animal and other toothed whales have yet to be found, its importance as a part of the evolutionary history of marine mammals cannot be understated. It raises fascinating questions regarding what evolutionary pressures would push the cetacean body plan to exploit the ocean floor, and what kind of environmental and biological factors made this the best evolutionary route for toothed whales off of the Pacific coast of South America.

[riverofhistory]

Episode 6: The Age of Mammals

The following is the transcript for the sixth episode of On the River of History.

For the link to the actual podcast, go here. (Beginning with Part 1)

Part 1

Greetings everyone and welcome to episode 6 of On the River of History. I’m your host, Joan Turmelle, historian in residence.

Welcome to the Cenozoic Era! This is our geologic era, the one to which we’re currently still apart of. The last 66 million years of the Earth’s history, from the great extinction event at the end of the Cretaceous Period, encompasses the development of the modern world – Cenozoic, translated, means “recent life”. In essence, we’ll be staying in the Cenozoic for the remainder of this podcast. Like the Mesozoic, the Cenozoic encompasses three periods, but because of the sheer number of important events that unfolded within this time, it is perhaps more feasible to progress through this time by epochs, those categories of time that make up periods.

The first period of the Cenozoic is the Paleogene, 66 million to 23.03 million years ago, and the first epoch of that time is the Paleocene, which ended 56 million years ago. The Earth’s continents were still slowly moving northward and outward, with India in particular going at a rapid pace towards Eurasia. It, along with Africa, South America, Antarctica, Sahul (made of Australia and New Guinea), and Zealandia (comprising what will become New Zealand and New Caledonia) were all disconnected and completely surrounded by ocean, while Eurasia and North America were connected by minor land bridges. The Atlantic Ocean was still very thin compared to today, being about half its current width, and the seas around Eurasia were rather shallow.

The dreaded combination of environmental changes and the severe bolide impact that closed the Mesozoic Era had proved to not be as dramatic as the end-Permian extinction event, meaning that life only tool a couple hundred thousand years to recover rather than a few million. The oceans and the land remained desolate places in many regions for a short time. Marine communities were lesser for the better, inhabited by mollusks, echinoderms, and other invertebrate groups that were smaller than their ancestors, a similar situation to what occurred after the Permian. For a brief while, crinoids bloomed, populating the shallow seas like opportunistic weeds. In fact, most of the marine life at the start of the Paleocene were essentially species that could sustain themselves on very little plankton, which themselves were still suffering from their losses. The chalk-forming coccolithophores would never again bloom as much as they had. There were many lineages of fishes that survived the Cretaceous extinction, and they too were not very common during this time. On land, the situation was not any better. There was a short burst in the number of ferns, which often happens after a major catastrophe as their spores are easier to disperse than seeds. They rely on the wind, rather than animals, to carry them to new places, which was difficult for seed plants as animal diversity has low. Granted, many lineages made it through the extinction, even the dinosaurs (remember, one lineage of birds survived). Basically, though there were survivors among plants and animals, their numbers were low as great food webs were still recovering.

But recover they soon did. Global temperatures rose as the last remnants of the great impact-winter ceased, and the world was soon able to support great swarms of living things again. The seas returned to similar numbers of diversity as the previous Cretaceous, though there was a notable lack of giant marine reptiles this time around. Corals and sponges dotted the seafloor, while mollusks and arthropods scurried and swam about between them. The land’s ecosystems were abounding with the descendants of the surviving organisms. Flowering plants were now the dominant land plants on the Earth, with the gymnosperms and ferns second in diversity. Many parts of the world were cloaked in forests of redwoods and cypress trees, but now they were sharing their spaces with broadleaved angiosperms. For frame of reference, think of the floras commonly found in Latin American rainforests: colorful fruiting trees like citrus, papaya, avocado, and mango, climbing plants and vines that support their weight on tree trunks and branches, and palm trees. Now picture these species growing in places like modern-day Wyoming, France, and China. Remarkable right? For much of the Paleocene, the world was covered in tropical and subtropical forests and these plants supported a growing number of animal species.

From the moths emerged a new lineage, the butterflies, distinguished from their ancestors by their often clubbed antennae (as opposed to a moth’s feather-like antennae) and their habit of folding their wings vertically from their bodies (while moths mostly fold them outwards behind them or to their sides). Young butterflies are called caterpillars and these larvae were now content to attack the hordes of new flowering plants that were evolving. In response, many plants developed defense mechanisms to keep these caterpillars from fully destroying their leaves, including spines and sticky trapping-fluids and even toxins that repel would-be attackers. As an added bonus for the plants, some species of wasps began to hunt caterpillars and parasitize them, a step-up for those species who preyed on beetle grubs during the Cretaceous.

Our three living lineages of mammals survived into the Paleocene, alongside a few other groups that eventually would not make it to the present day. Mammals lasted through the extinction event because of two key factors: they were all small enough to seek shelter in inconspicuous places like burrows, and they had strong omnivorous diets that allowed them to live on any conceivable food source. Now that most of the predatory dinosaurs that feasted on them were gone, and that the niches of these and all the other giant reptiles were left open, the mammals had a chance to take over the roles of major herbivores and carnivores in their ecosystems. However, they did not suddenly begin producing multi-ton species, and for the duration of the Paleocene the largest the mammals got was as big as a sheep or a large dog. Despite this, there was a great diversity present, with more and more of the modern mammal groups establishing themselves. In the Cretaceous, the monotremes had a global range, while the marsupials and their relatives were confined to Asia. Marsupials had made it to North America during the Cretaceous, but their numbers were decimated following the Cretaceous extinction, and only a few tiny populations were left. It was in South America, where they survived in significant numbers, that they left their mark. Paleocene South America in particular was rampant with the ancestors of the opossums, who were mostly arboreal marsupials that fed on insects and leaves.

That third great group of living mammals, the placentals, were to be the ones who dominated that continent, and indeed most of the others as well. Today, placental mammals are classified into four major groups, a scheme that was slowly uncovered by anatomical studies and only later cemented by genetic testing. The xenarthrans – including sloths, anteaters, and armadillos – with slow metabolism and a peculiar arrangement in the bones of their hip and spine. The afrotheres – including elephants, sea cows, and a host of smaller groups – with a large number of vertebrae and the setting of their permanent teeth occurring later than most mammals. The laurasiatheres – including bats, shrews, and the majority of carnivorous and hoofed mammals – primarily united by genetic traits, with no known anatomical similarities uncovered yet. And finally, Euarchontoglires – including rodents, rabbits, and primates – with particular adaptations in the skull. If some of these complex names sound familiar, they denote the place of origin for these placental groups. Afrotherians evolved on the African continent; Laurasiatheres originated in ancient Laurasia before it split into North America and Eurasia; Xenarthra was a South American development; and Euarchontoglires appears to have risen in somewhere in Eurasia. All the current evidence we have indicates that these groups were present at the start of the Paleocene.

Among many of these placental mammal groups were a host of strange lineages that left no descendants, but it was these that were to become the prominent predators and prey of the Paleocene mammals. The herbivores were represented by slow-moving, stocky-bodied animals that walked on the soles of their feet. These were browsers who cropped up plants with low-crowned teeth, that is, teeth that is shortened and flattened. The best studies we have suggest that these mammals were at least related to living hoofed mammals or ungulates, but their feet were tipped with blunt claws rather than hooves. One group of these, the taeniodonts, shifted their diet to feast on hard roots and tubers by extending their front teeth into tusks and chisels. Hunting these were the creodonts, a now-extinct group with possible ties to living carnivorans (the group that includes the cats, dogs, weasels, and seals of today). Like the proto-ungulates, creodonts moved on the soles of their feet, but they sported clawed toes and had rows of sharp, sheering teeth in their jaws. As far as their behaviors are concerned, they do not appear to have grabbed and pinned down their prey like living cats and bears do, but instead relied solely on their head and jaws to kill.

From the laurasiatheres stemmed the earliest carnivorans, who shared hunting grounds with creodonts, though they began as small, weasel-like animals with long, bushy tails. Also present were the two lines of living hoofed mammals: the perissodactyls (those with an odd-number of toes) and the artiodactyls (those with an even-number of tors). These related herbivores started out very different from each other, with the perissodactyls originating as long-bodied and long-tailed runners, having undifferentiated feet. This group would give rise to the horses, rhinos, and tapirs. Artiodactyls originated as petite animals with thin legs ending in cloven-hooves, and they seem to have been able to hop as well as run. This group is known today by the cattle, deer, pigs, and camels, among others. In Euarchontoglires, the first rodents were squirrel-like animals, already having the continuously-growing, chiseling, buck teeth that characterize the group today. These mammals would have foraged for nuts and seeds in the trees and along the undergrowth, where they encountered early treeshrews and colugos: two related lineages that feed on insects and leaves, respectively. Colugos in particular are fascinating in that they developed membranous structures along their bodies and became gliding mammals that live in trees.

Like mammals, living birds flourished at the beginning of the Paleocene, and it was the lineage that these belonged to, the Neornithes, that were the only dinosaurs to escape the Mesozoic. Neornithine birds are characterized by fully toothless beaks, and it appears that they survived because they were originally ground-dwelling species, while most of the other bird groups inhabited trees (which would have been destroyed in the ensuing chaos). As forests returned to the world, birds experimented with new lifestyles and some became arboreal. The Paleocene marks the evolution of the first waterfowl, gamefowl, and owls. By 62 million years ago, a group of birds had begun residing near seashores and adapted their wings into paddle-like structures. They had long bills for catching fish and webbed-feet to help them propel through water. These were the first penguins, meaning that birds had already returned to the seas almost immediately after the Cretaceous. Some birds lost the ability of flight and relied on their strong and lengthy limbs to carry them around the ground. Among these birds were the ratites, who today include ostriches, emus, and rheas, but there was another group of birds with affinities to ducks and pheasants that grew to enormous sizes: the gastornithids. They had very large, thick beaks for cracking open hard fruits and snapping up twiggy plants.

The true stars of the Paleocene were the other reptiles, like crocodilians, turtles, and lizards. Though the Cenozoic is often titled the Age of Mammals, for a brief time at its start the largest and most significant members of the fauna were sauropsids. This point in time is beautifully illustrated in the Cerrejón Formation of Colombia, where 60-58 million years ago there was an entire community of giant reptiles. Though crocodiles were abundant, they were not the dominant predators. They fell prey to two species: a turtle, Carbonemys, with an almost six-foot shell, and the snake Titanoboa, which spanned 42 feet in length and weighed over a ton. But faunas like this were not to last long, and as the Paleocene closed it would be the mammals who would come to dominant the land.  

Part 2

The hothouse world of the Paleocene epoch only grew in temperature as it passed into the Eocene epoch, 56 million to 33.9 million years ago. The boundary between the two epochs, only lasting around 200,000 years, is known by paleontologists as the Paleocene-Eocene Thermal Maximum, because global temperatures soared to an average of 74 degrees Fahrenheit. This extreme jump in heat and humidity has been linked to a spike in methane emissions from the ocean floor as frozen reservoirs of the gas are thawed due to rising ocean temperatures. As we’ve seen, the oceans had already been warming for some time, so this change in temperatures would have easily released all this methane, which (being a greenhouse gas) trapped in oncoming heat from the Sun and warmed the planet. The evidence for this occurrence has been found in the way that certain forms of carbon were produced by fossil plankton from this time that match a sudden methane spike. The circulation of ocean currents brought warm water from the poles in contact with warmer water from the equator, meaning that the entire marine environment was kept consistently hot. Tropical forests did so remarkably well during the early Eocene that they stretched from pole to pole. Quite literally, in rocks found as far north as Greenland there were communities of palms, fruiting trees, and reptiles.      

The Paleocene- Eocene Thermal Maximum affected a world that was still slowly changing into a recognizable form. Of importance to note for the early Eocene was one key difference in geology. In the western hemisphere, chunks of land that had begun rifting from the northwest tip of South America were slowly moving eastwards between that and North America since the late Cretaceous. Now, around 55 to 40 million years ago, these small islands had been establishing themselves near their modern localities, forming the earliest recognizable stages of the Caribbean islands. Though, briefly, the islands of Hispaniola and Puerto Rico were to be found underneath Cuba.

In the warming oceans, planktonic species boomed and increased with diversity, with diatoms, dinoflagellates, and even coccolithophores expanding their ranges. Among these groups were the shelled foraminifera, who had already evolved over 540 million years ago. I bring them up now because we hold the Cenozoic species in very high regard: forams are one of the plankton groups that turn into oil. The process for making oil is similar to that of coal, where the dead remains of the plankton are pressed deep into the Earth and superheated till they develop into oil reserves. And just like the great trees of the Carboniferous rocks, all the carbon found in foraminiferan shells is still there. Of related interest are a subgroup of foraminifera called nummulitids, who left their giant shells behind in limestone found in present-day Egypt. It was from these rocks that the Egyptians would use to build the Sphinx and the Great Pyramids.

For the first time since the Cretaceous, reef-forming species returned in the form of the scleractinian corals who were now spreading all across the shallow-surface waters of the Earth, particularly in the Pacific and Tethys Oceans and the western Atlantic. Many of the species we know today – the brain corals, staghorn corals, and mushroom corals – were present in greater numbers than ever before. There was another new marine habitat that formed during the Eocene, the fields of seagrasses. Seagrass is not related to the grasses we know today, but instead belong to the arum, water-plantain, and pondweed group. These new and growing ecosystems supported a remarkable jump in the diversity of marine invertebrates, with mollusks, arthropods, and echinoderms in particular doing very well. Crabs and lobsters hunted among the reefs, while cowries, pen snails, and other gastropods inched along the seabed. Among the urchins emerged the very first sand dollars, who are flatter and have smaller spines than their ancestors. With the advent of the coral reefs emerged a new collection of ray-finned fishes, including all of the popular and colorful lineages like the wrasses, puffers, surgeonfishes, angelfishes, and triggerfishes. The first hammerhead and thresher sharks patrolled the waters, using unique adaptations compared to their streamlined relatives. They were joined by many lineages of giant sharks, who were able to thrive in the warmer Eocene waters and go after larger bodied prey.  

There was one group of mammals who would quickly join their very distant relatives and grow into one of the most iconic and beloved of all marine species. Around 53 million years ago, two lineages of semi-aquatic mammals diverged from each other. One would prefer to stay amphibious and developed large bodies for processing land plants, becoming the ancestors of hippos. The other gradually trekked deeper and deeper into rivers and lakes and relied more on fishes for sustenance. Among these was Pakicetus, looking like a cross between a wolf and a deer, with an elongated body, tiny hooves on its feet, and large jaws full of slicing teeth. What was really peculiar about this mammal was the way that its eyes were found high on their head and how the bones in its ears were shaped for hearing underwater sounds. Later species completely abandoned a semi-aquatic lifestyle and devoted their entire lives to living in freshwater. One of these was Ambulocetus, who had webbed fingers and toes and very streamlined body like an otter. Its vertebrae were very flexible, and the animal undulated as it swam after fish. Still later the body lengthened and became much more streamlined as the animals began to rely more on their tails than their hindlimbs for swimming. It wouldn’t be long until the forelimbs developed into paddles, while the hindlimbs became much reduced as the tail grew and supported paired fins at its base. The nostrils changed too, moving further and further up the snout till they lay at the center of the head, where the eyes had moved down to the sides of their skulls. Between all this anatomical change, these mammals moved from freshwater regions to the oceans. This culminated in the 66-foot Basilosaurus and it was when animals like these lived, 40-35 million years ago, that the oceans were home to the whales. That we understand how whales evolved from land mammals and just who their closest relatives are both today and in the fossil record is a testament to the increasingly sophisticated techniques of paleontologists and other researchers in recent times.

On land, the mammals had begun to take over the Earth. In the early Eocene, the largest species had grown to the size of domestic cattle, but by the end of this epoch they had become as large as elephants. Because the Earth’s continents provide a unique perspective into the biogeography of their faunas, I will be examining mammal evolution on a continent-by-continent basis. Around 55 million years ago, the continents of Eurasia and North America were still connected together by land bridges. This allowed many of the newly evolving lineages to spread out to other lands and compete with their native species for the same resources. In North America, the first horses evolved. These were small mammals, only around 2 feet in length (comparable to some dog breeds), that ran in the underbrush of the tropical forests. They had four toes on their forefeet and three toes on their hindfeet, tipped with little hooves. These early horses were browsers who fed on the leaves of bushes with simple, chewing teeth. Over the Eocene epoch, they grew in size and began to displace some of the older hooved mammals that had dominated the Paleocene before them. Among carnivorous mammals, the creodonts were still doing well and the early weasel-like carnivorans continued to chase after small prey. The extensive tropical forests had encouraged the spread of flying insects, and this allowed one group of laurasiatherian mammals to go after them as a food source. Perhaps beginning as arboreal mammals, they developed a membranous skin across their bodies, supported by their arms and fingers, which elongated and formed a wing. These were the earliest bats, with fossils showing that they already had echolocating abilities 52 million years ago.

In Eurasia, there were clear signs of changing faunas both in Europe and eastern Asia. The squirrel-like early rodents that evolved in the Paleocene of Asia had by now spread into North America and Europe and diverged into their key lineages, including the myomorphs (mice, rats, and kin) and the squirrel and dormouse group. Related to the rodents are the lagomorphs or rabbit lineage, who evolved in Asia alongside them. The earliest members of this lineage are not hopping, long-eared animals yet, but rather scampering, marmot-like creatures. One lineage of laurasiatheres are the lipotyphlans, which is the group of mammals that includes the shrews, moles, and hedgehogs of today. Fossils indicate that this lineage evolved either in North America or Europe, with early shrews appearing in North America, and early moles and hedgehogs appearing in Europe by the middle of the Eocene. One curious lineage, the solenodons, appear to have already evolved and settled in the Caribbean, where they’ve remained ever since. In Africa, still an island continent, the afrotheres were diverging into their present-day lineages. Of primary interest are two groups that began much like the ancestors of whales and hippos did, as similar animals in both shape and habitat. In this case, the tethytheres were large, pot-bellied, pig-like animals living a semi-aquatic lifestyle and eating a wide range of different plants. One lineage of these began to develop a short proboscis or fleshy, prehensile nose that aided them in gripping leaves and twigs. Their foreheads became raised and they began to grow out their incisor teeth. This lineage became the proboscideans, the ancestors of the modern elephants. The other lineage remained semi-aquatic, but began to increasingly rely on aquatic resources as they thickened their bones to help them dive deeper and stay underwater for longer periods of time. Their snouts became downturned as their lips grew fleshy: a good adaptation if you want to feast on the groves of seagrasses that were now growing all about. Eventually, their nostrils moved to the tops of their snouts and their hind limbs became diminished while their forelimbs flattened into a paddle dotted with nails. This lineage begat the first sea cows, and became the second group of marine mammals, after the whales.

South America was another island continent, and it quickly grew to be the odd-one out for placental mammal evolution. Several groups of laurasiatheres, related to the odd-toed perissodactyls, became isolated on this great landmass. The only mammals there to greet them were the marsupials, who were mostly carnivores, and the xenarthrans, who had by now also produced the earliest armadillos. Thus, there were niches open for herbivorous animals, and they had begun to converge in body plan with their distant relatives in the northern hemisphere. In Sahul, the situation was a little different, with the marsupials now having the upper hand as the dominant group of mammals. Fossils indicate that marsupials arrived in Sahul from South America via Antarctica by 55 million years ago, and it was following that when some of them had begun to diversify into their modern lineages. They coexisted with a few placental groups, including bats, but these would remain minor elements of the Sahulan fauna.

At the end of the early Eocene, the global climate finally began to cool. Over a period of 15 million years, surface temperatures gradually crept downward, with no indication that carbon dioxide levels were changing in any significant way. It is thus unclear as to what caused this change in climate, but its effects were certainly marked in the responses of plants and animals. For one, the one-world rainforest that dominated the early Eocene had begun to be replaced by subtropical, and then deciduous temperate forests. Oaks, sycamores, pines, walnuts, and other species of gymnosperm and angiosperm trees were spreading around the planet, particularly in the great expanses of Eurasia and North America. On land, these forests supported larger and larger herbivores. In North America, horses had gotten larger and had lost one of the toes on their forefeet. Sharing that land were many new artiodactyl groups, including the first camels that lacked humps and were tiny enough to sit on your lap. The largest land mammals in the world included the dinoceratans, who ranged in Asia as well as North America. They reached lengths of 13 feet long and were often characterized by their strange bony knobs that protruded from their skulls, the function of which seems tied to sexual selection. Their often sported elongated canine teeth, tusks really, from their upper jaws, and these too appear to have been used for combat between individuals. Larger still were the brontotheres, which were closely related to horses but grew as large as 16 feet. Like the dinoceratans, they also had unique head-gear, this time a forked and flattened protuberance at the base of the snout. The structure of these ornaments has been suggested to be display structures that also could be swung at the sides of rivals, rather than head-on. These giant herbivores would have not been severely affected by any would-be predators, including a newly evolved group called the nimravids. These resembled cats, and even sported saber-teeth, but they were a case of convergent evolution that left no living descendants. They, along with the creodonts, were the main predatory mammals of the later Eocene.  

The Eocene was a very good time for bird evolution too, and it marked the development of many charismatic lineages. One remarkable transformation occurred in the history of the swifts, who evolved early in the epoch. Their ancestors were nocturnal, forest dwelling birds, the same that gave rise to the whippoorwills and frogmouths. Over time, they shrunk in size, and reduced their hindlegs as they became more reliant on an aerial existence chasing after fast-flying insects. With a switch to diurnal, or day-living, activity, the swifts had arrived. Early cuckoos, turacos, mousebirds, hawks, parrots, and perching birds inhabited the trees, while early rails, cranes, loons, and herons patrolled river and lake environments, feasting on the abundance of newly evolving freshwater fishes like carp and minnows. Some birds had joined the penguins near the coasts, including the first petrels, frigatebirds, and a group of now-extinct species called the pelagornithids. These were false-toothed birds, meaning that their beaks were lined with serrated edges that functioned like teeth which could stab fish they caught. Pelagornithids have been suggested to belong to the lineage that includes ducks, pheasants, and their relatives, but the largest sported wingspans of 20 feet.  

The gradual cooling that marked the middle and late Eocene epoch erupted into full swing around 36 million years ago when a sudden drop in global temperatures ended the life histories of many animal and plant lineages in the oceans and on land. While the previous bout of cooling lacked any good explanation, we at least recognize that this extremely short event was the result of the final severing of Sahul and South America from Antarctica. The three continents had been separating for some time now, but there was now such significant ocean between them that a new current formed that circled the entirety of Antarctica. This change in ocean circulation meant that the cycle of continuously warm water was interrupted, and the deep ocean waters off the coasts of Antarctica grew very cold as a result. During the long drop in temperatures at the tail-end of the epoch, there was just enough cool for small glaciers to form in Antarctica, but now with this change they grew greatly in size and width. All of that polar ice further cooled the climate, and the Eocene epoch ended with a small extinction event where many of the species that had already been adapted to the cooling world couldn’t react in time to the rapid shift. Incidentally, none of this global climate change was in any way affected by the massive bolide impact that struck the Chesapeake bay around 35.5 million years ago. Nothing too major.

Part 3

The Oligocene Epoch followed the Eocene, 33.9 million to 23.03 million years ago, and was characterized by the biggest geologic change in recent history. For millions of years since the Cretaceous, India had been moving northward at a rapid pace compared to the other continents. By the later part of the Eocene, the southern lands of Eurasia were buckling and folding as the subcontinent came closer towards it. Finally, by the beginning of the Oligocene, India had pushed itself into Eurasia. The violent contact between the two continents pushed up vast areas of land between them, beginning the formation of a new series of mountains, the Himalayas. Simultaneously, in a process that was also continuing from the Eocene, the African continent had been moving north towards Europe and Southwest Asia. Keep in mind that the modern land of Arabia belonged to the African continent at this time, though it was located on a separate tectonic plate. When Africa pushed enough into Europe, some of the land there began to rise upwards as well, forming the Alps, while chunks of land moved from the north and collided with Europe, establishing the Greek and Italian peninsulas. The Arabian plate hit Southwest Asia and brought up the Iranian Plateau. The collision of India with Eurasia marked the end of the Tethys Ocean, now replaced with the Indian Ocean. In the Pacific around 28 million years ago, the very first islands of the Hawaiian archipelago were forming, born of a chain of undersea volcanic eruptions, and Fiji formed a few million years earlier via the movement of tectonic plates.  

These new mountains and highland regions contributed to the global cooling that ended the Eocene, alongside the growing Antarctic ice-sheet. In addition, a new ocean current, the North Atlantic Deep Water current, formed as the northern seas of Europe and North America had separated long enough for deeper oceans to form. Thus, the Oligocene was a cool time in the Cenozoic Era. Cold-water adapted marine organisms did very well in the colder oceans, while the numbers of coral reefs and tropical-sea species receded to warmer regions around the Equator. There was one particular site along eastern Sahul where coral species started building structures and laying the roots of the Great Barrier Reef. Some species of ray-finned fishes moved down into the deeper and darker parts of the open ocean, where they formed symbiotic relationships with glowing bacteria that they incorporated into their bodies. This gave them bioluminescence, using light to catch prey or attract mates, and some of the species that evolved from these fishes include the viperfish and hatchetfish, who would become opportunistic predators in these quiet realms. In response to the cooling oceans, many of the early whales had died out, but the remaining species still had plenty of other marine organisms to eat. For example, our modern krill lineages had evolved in the cool northern and southern oceans, and this proved to be a valuable food source for one branch of the whale family. Some of these whales had reduced or lost their teeth and went after their new prey by sucking them up with a fleshy mouth. Later descendants began to sprout filamentous folds along their jaws to filter the krill from the water. This lineage became the baleen whales, represented today by the humpback, blue, and right whales – indeed they will become the largest mammals that ever lived. Another lineage of whales retained their teeth and continued to go after cold-water fishes and squid, but they had developed a melon atop their heads. The melon serves as an organ that produces sounds, and the descendants of these mammals became the toothed whales, which include the dolphins and porpoises. On the coasts, there was another group of land mammal, related to bears and weasels, that started transitioning into a marine ecosystem. These were the ancestors of the pinnipeds: the seals, sea lions, and walruses of today. Fossil remains tell us that early pinnipeds were otter-like mammals that had webbed feet for swimming, but for the Oligocene, however, these animals were still primarily terrestrial.

The cooling and drying conditions of the planet were beginning to have major impacts on land ecosystems. Tropical and subtropical forests receded further and further into equatorial regions, and the dense deciduous forests gave way to more open woodlands and fields. In South America, this change was most drastic, as a brand new habitat developed in the east and southern regions: the pampas. This was a grassland, an environment where grass is the dominant plant and underpins the entire ecology. I’ve neglected to talk about grass, even though it appears to have evolved and diversified in the Late Cretaceous, because it wasn’t until the Oligocene onwards that these plants began to change the world. Grasses are angiosperms, with often tiny flowers that are not pollinated by insects but blown by the wind. They’re hardy and tough, with their leaves incorporating tiny silica structures called phytoliths that serve as protection from herbivores. This did not prevent some of the hoofed mammals there from venturing out onto the pampa and eating the grass. As the phytoliths can wear down teeth, these animals had to modify their teeth into grazing tools that continuously grew throughout their life. There were also groups of flightless birds called cariamiforms that began to trek out into the grasslands after prey, where they lengthened their legs to become pursuit predators. Arriving from the Atlantic were the caviomorphs, a lineage of rodents that includes the ancestors of the chinchillas, guinea pigs, and pacaranas. These rodents evolved in Africa and found their way to this continent, which could have involved a freak accident involving a storm and some islands of floating vegetation that they could have subsisted on during an unintended rafting journey.

In North America, where open woodlands spread from shore to shore, many of the animals in the earlier subtropical and deciduous forests had either gone extinct or adapted to their new environments. In one instance, crocodiles had all but vanished from the wetlands, only to be replaced by alligators, who could weather the cooler waters and even go into a dormant state and sleep out harsher conditions. Tortoises, in contrast, diversified and spread out across many different habitats, where they often grew to enormous sizes. In fact, giant tortoises had a constant presence across most continents from the majority of the Cenozoic Era, where they feasted on grasses and other low- to medium-growing plants. Mammalian faunas had shifted too. Gone were the great brontotheres and dinoceratans, replaced by different species of rhinos as the dominant herbivores. The rhinoceroses of the Oligocene would have looked only superficially similar to those of today, with some species lacking horns altogether while others sprouted a forked pair. Horses remained browsing animals, though they had now grown much larger in size, with longer limbs and more reduced toes. The camels browsed alongside them, still behaving as running, gazelle-like mammals. These were now joined by early deer, who did not (at first) have their characteristic antlers. They were small and must have timidly foraged in whatever foliage they could find. There were other, now extinct, groups of mammals sharing the North American woodlands with these more familiar groups, including the oreodonts, who looked like a cross between a camel, a sheep, and a pig. Oreodonts were very common and must have formed dense colonies as they stripped leaves from bushes and shrubs. Another group, the entelodonts, were relatives of hippos, and even sported elongated teeth in their massive heads; though, unlike hippos, they ate harder brush and seem to have supplemented their diet with smaller mammals. Hunting these hoofed mammals were the nimravids, who survived the Eocene, now joined by the first dogs or canids. The earliest dogs were almost weasel-like and scurried after smaller prey animals. The weasel family or mustelids, funnily enough, had evolved in North America by this time.  

Eurasia was experiencing shifts in mammalian faunas too, as groups that resided in the eastern side of the continent moved towards Europe and displaced the species living there. Many of the older lineages, like the creodonts and the archaic hoofed mammals died out, replaced by early pigs, deer, and bears. The first cats evolved here too, with retractable claws for climbing trees, where they originally lived. Southwest Asia sported a truly heavy-weight group of mammals, the indricotheres, which were a lineage of rhinoceroses that lengthened their heads and necks to feed on the leaves of trees. They were among the largest that land mammals ever got, reaching a height of 16 feet at the shoulders and a weight of 22 metric tons. The biggest land mammals never reached the size of titanosaurs, because unlike these dinosaurs their bones were solid, not hollow, and this would have meant that their limbs could not support their weight without breaking. In one strange twist, the first hummingbirds had diverged from the ancestors that gave rise to swifts, becoming pollinating animals. These birds, first evolved in Eurasia, later migrated into South America and continued their history there. The African mammals continued to evolve in isolation, with the proboscideans bringing forth a new lineage, the mastodons. They had elongated incisor teeth, now proper tusks, and flattened heads. These great herbivores coexisted with their relatives, the hyraxes, which are represented today by small, grass-eating rabbit-like creatures but once came in a variety of shapes and sizes. Sahul’s history is a bit of a pickle for paleontologists at the moment, but we can at least be confident that the main groups of marsupials and monotremes were going about their lives.  

There was a brief rise in temperatures at the end of the Oligocene as part of Antarctica’s ice sheets thawed, and the following epoch, the Miocene (23.03 million to 5.3 million years ago) was mostly characterized by a slightly warmer climate than its predecessor, but it was still much cooler than the Eocene. The Miocene marks a new period that began in Earth’s history, the Neogene, which lasted until 2.58 million years ago. The Himalayas continued to rise, and the continued pushing of Africa on Europe brought up the Atlas mountains that line Morocco, Algeria, and Tunisia today. This impact of Africa on Europe had nearly enclosed the ocean and brought the Mediterranean Sea into existence. Early in the Miocene, the Rockies had started to form in western North America, with the Colorado plateau following suit by the middle of the epoch. It was there that the earliest stages of the Grand Canyon were taking hold about 17 million years ago as rivers slowly carved through the sedimentary rocks. Around 15 million years ago, tectonic activity in east Asia had officially sectioned off the Japanese archipelago from the greater landmass. Further in the southeast Pacific, Samoa and its neighboring islands were established around 23 million years ago, and the Marquesas islands wouldn’t begin to form until 5.5 million years ago.

With the conditions just right, grasslands began to spring up and took over much of the Earth’s surface as the forests continued to recede. In North America there were the prairies; in Africa the savannas; and throughout Central Asia the steppes. Grasses remained very tough plants, and they were able to regenerate their numbers following fires by placing their roots deep into the ground. That way, when a fire clears, they’re able to sprout up quickly because those organs were separated from the flames. Another group of flowering plants was able to use this phenomenon to their advantage, able to set root and grow in the charred soil as the grass returned. These were the composites, which include the modern daisies, dandelions, sunflowers, chrysanthemums, and several food plants like lettuce and artichoke. Their hardy reputation and their ability to spread rapidly has earned them a harsh reputation as weeds among people today. Despite this, composites proved to be a valuable food source, as did the grasses, and this prompted many of the world’s land vertebrates to leave the forests for good and enter this new environment.

The perching birds, who evolved in the Oligocene, are characterized by their unique foot, which has special tendons and ligaments that close up the foot into a perch when on branches. They seem to have evolved in Sahul and spread out from there onto the other continents, with one subgroup, the songbirds, diversifying with the spread of the grasslands. Songbirds sing via an organ in their throat called a syrinx, which functions like a voice-box for making and amplifying complex calls. This birdsong is used to call mates, and each species has a distinct voice. The descendants of those ancestral songbirds include many familiar species like the cardinals, finches, robins, bluebirds, crows, and wrens. Among non-avian reptiles the snakes had expanded in variety, with some lineages becoming accomplished predators within the grasses, using venomous fangs to subdue and kill their prey. These prey items included amphibians like frogs, who also experienced a burst of biodiversity during this time.  

Miocene mammals responded very well to the grasslands. Across the continents, rodents truly began to grow in numbers, paving the way for their lineage to be the biggest group of mammals on Earth. The myomorphs (or mouse-like rodents) really benefitted from the grasslands, with many adapting to life among the grassy-forests or taking up a burrowing lifestyle. One group, the cricetids, developed into the first voles, hamsters, and lemmings, while another group, the murids, gave rise to the proper mice, rats, and gerbils that many among our populace view as pets and pests. Another distant lineage of rodents, the castorids, included some species that formed strange corkscrew burrows that extended over eight feet into the ground. These larger rodents would give rise to the beavers. Rabbits and their kin, meanwhile, remained running animals, though uncommon in their environments.

Part 4  

In North America, the hoofed mammals there were beginning to establish larger and larger sizes and they in particular adapted their bodies to the prairies in remarkable ways. In general, hoofed mammals lengthened their legs and thinned them into sturdy yet spindly structures. Their feet changed too, with more toes being lost until just one or two remained, and their hooves became more prominent, and their teeth had changed into high-crowns that continuously grew in life. For example, the horses switched from forests to grasslands and grew bigger. To run faster, they had increased the size of their middle toes and reduced those flanking them. With all the weight now being supported on one hoofed toe, they could gain traction as they pushed through the fields and run much faster than they ever could before. Camels too, grew larger and reduced their toes, till the foot was reduced to a double-toed, padded sole. Some were remarkably fast animals, while others grew so big that they could feast from treetops and look over all their neighbors. These camels, including Aepycamelus, resembled giraffes with elongated necks and long, thin limbs. In contrast, deer remained mostly woodland animals, and had already begun to develop antlers, though many species also sported sharp canines for fighting rivals. Joining the North American fauna were the pronghorns, who were much more diverse than today, represented by many species with branched, pointed, and curly horns. Predatory mammals too changed to suit the grasslands. The nimravids were still present, but now they were in decline, being replaced by the dogs who had grown into much larger hunters on the plains. In parallel with herbivores, carnivores started lengthening their legs and traded their climbing feet for compressed, running feet with pads on their ends. They supported their weight on their toes instead of the soles of their feet. In response to the rise of pursuit predators, grassland herbivores not only began to run faster, groups began to coalesce into herds for protection. Even with this, the predators responded, with some forming packs that worked together to single out prey and take them down.

Sea levels began to drop around 18 million years ago as Antarctica’s ice-sheet returned and began to engulf the continent. Grand forests developed in the northern hemisphere, where the gymnosperms would outdo the angiosperms and radiate into new species of pine, spruce, and fir. The drop in sea levels allowed new land bridges to form, with the one between North America and Eurasia growing in size to become the region of Beringia. Now that Africa and Asia had collided together, the falling sea levels permitted the creation of the Arabian Peninsula, meaning that Africa was no longer and island continent. These changes in geography facilitated many mass migrations of animal life across the continents, allowing more faunas to be displaced and setting up the primary distributions of animal groups today.

The strange panoply of African mammals, the afrotheres, were now free to expand to other regions. The proboscideans left Africa and the mastodons were established on Eurasia and North America. Related to the mastodons were the gomphotheres that evolved in Eurasia. These large mammals had modified their lower jaws into flattened spoons and shovels, tipped at their ends with blunt and flattened teeth that would have helped them scrap tree bark and dig up roots. These shared the grasslands and woods of European and Asia with a host of different species. Entering Africa from Eurasia was a motherload of new placental groups, including dogs, cats, pigs, and rhinos. Two new groups of artiodactyls evolved in Eurasia during the Miocene and also made ventures into Africa. The first of these were the giraffids, which today is represented by a few species of long-necked, spotted giraffes and the elusive forest-dwelling okapi. In their youth, however, they were a varied bunch, with many deer and antelope like forms. The other was the bovids, the group that includes cattle, sheep, goats, and antelope. They sport horns atop their heads that are sheathed by keratin (the same substance as our hair and fingernails) and these organs continuously grow throughout their lives. The earliest bovids, incidentally, resembled small antelopes, and it was only later that the burly and strong buffaloes and cattle evolved. Also developing in Eurasia were the cats, who now had diversified into a number of different groups, including the panthers or big cats, the lynxes, the pumas and cheetahs, and the wildcats. They too entered Africa, as well as North America. So, in essence, most of the animals that define Africa – the giraffe, the black rhinoceros, the cape buffalo, the gazelle, the wild dog, and the lion – are relative new comers in the Age of Mammals.  

South America, still, was an island continent, and its fauna continued to flourish in the pampa, the oldest grasslands in the world. There were some new faces, however. The other groups of xenarthrans, the sloths and anteaters, were now on the scene, with the former feasting on the leaves of trees and shrubs while the latter adapted their snouts and tongues towards the consumption of termites. The native hoofed mammals had grown in size and diversity and they came to resemble more familiar mammals overseas, like hippos, rhinos, antelope, horses, and rabbits. Some relatives of the marsupials, like the saber-toothed Thylacosmilus and the dog-like Borhyaena, became great predators in their ecosystems. Sharing their hunting grounds were the descendants of those long-legged running cariamiform birds. Called phorusrhacids, their heads grew in size and their bills were sharped at their tips. They could reach over 9 feet tall, delivering sharp kicks to their prey and grabbing small mammals in their jaws to shake them to death. There were giant birds in the air as well, including Argentavis, a relative of condors and turkey vultures but with a 23 foot wingspan. Like their living relatives, this bird would have probably been a scavenger as well.

Sahul’s fossil record becomes much better during the Miocene and we’re now able to get a good look at some of the animals that lived there. All of the modern marsupial groups were present, including the wombats, possums, dasyures, and kangaroos. Like South America, Sahul hosted a collection of large, flightless birds called dromornithids, although these were not predators but herbivores. They appear to have been related to modern waterfowl, like ducks, and you could picture these enormous birds walking along as their trails of young scurry behind them. There were other flightless birds here too, early emus and cassowaries, the later sporting a head-crest and sharp claws on their toes. Alongside a number of snakes and monitor lizards are the mekosuchine crocodiles, who were semi-aquatic hunters but seem to have been competent on dry land.

In the oceans, marine life was settling into more modern positions. Coral reefs grew in the warmer waters, nearer to the equator, and early cuttlefish patrolled the reefs in search of fish. In the more open oceans, the toothed whales had grown into a number of distinct lineages, including the sperm whales, the dolphins, and the first members of the narwhal family. Sharks and rays were diversifying too, with the earliest manta rays and basking sharks switching to a planktonic, filter-feeding lifestyle, of which the whale sharks had partaken of in the Oligocene. Among the filter-feeders were grand marine predators. Representatives of the sharks are seen in the evolution of megalodon, which has been estimated to have grown 52 feet in length. It has enormous teeth that lined jaws that could open 6 and a half feet wide. Megalodon sharks are known to have gone after whales because some remains of their prey show teeth imbedded in their vertebrae. Alongside these sharks were giant sperm whales, like Livyatan, with powerful jaws lined with curved teeth over a foot long. The modern groups of pinnipeds were now well established in the seas, including the walruses who started out with small canines and only later grew them out as long tusks.

The end of the Miocene is capped with a rather extraordinary event that unfolded between 6 million and 5.3 million years ago. While the Mediterranean Sea had been in place since the beginning of this epoch, global sea levels were dropping as Antarctica’s ice-sheet was growing. This was combined with the continuing movement of Africa into Europe, which closed off the Strait of Gibraltar between modern day Iberia and Morocco. Because of the nature of the Mediterranean, where the surrounding lands were very dry places, the sea began to evaporate rapidly. Over several periods of a few thousand years, the grand “lake” lowered more and more until finally, around 5.6 million years ago, the entire Mediterranean had dried into a basin dotted with small saltine-lakes. It wouldn’t be until 5.3 million years ago that the Strait of Gibraltar opened up again and the Atlantic poured back into the Mediterranean in a flooding event that has been estimated by some to have been torrential.

The Pliocene epoch ends the Neogene Period as a relatively short span of time, 5.3 million to 2.58 million years ago. Grasslands still dominated much of the world, while the temperate and tropical forests remained in some of the warmer regions. Changing ocean circulation promoted a brief period of warming during this time and their stirring of undersea nutrients encouraged marine communities to experience yet another period of diversity. New islands emerged in the Pacific, with Easter Island, Tahiti, and the Society Islands developing around 4.5 million years ago, and the Galápagos islands emerging through volcanic activity by 3 million years ago. Sahul was now in its present day location, with the lands that would become New Guinea bordering Southeast Asia.

After being separated since the Cretaceous Period, the two continents of the Americas had finally connected together through the Isthmus of Panama, which formed 3 million to 2.7 million years ago. The ramifications of this geologic event would forever change the fauna of North and South America. Prior to the joining of the continents, North America was home to a wide range of placental mammals, including horses, camels, dogs, bears, raccoons, and mustelids, all of which evolved there millions of years ago. Mastodons and gomphotheres had arrived there from Asia in the Miocene, adding some megafauna to the mix. South America had a much more unique fauna, full of armadillos, anteaters, sloths, marsupials, caviomorph rodents, native hoofed mammals, and giant flightless birds. Once the Isthmus of Panama was established, the animals on these two continents began to migrate in opposite directions and populate the new territory, in an event that paleontologists have dubbed the Great American Interchange. Sloths and armadillos moved into North America, including some enormous forms like the ground sloths. Marsupials finally returned there, of which one species – the opossum – survives today. Some of the South American caviomorphs made it into North America too, but like the marsupials only one held out, the porcupine. In contrast, it was the mammals from the northern continent that really disrupted South America. For the first time, bears, dogs, cats, raccoons, deer, camels, horses, and proboscideans entered that land. There was a period of competition between these immigrants and the already present carnivores and herbivores, but in the end the predatory marsupials, giant running birds, and native hoofed mammals were pushed into extinction.

By the Pliocene, most of the horses had died out, leaving one lineage left that had finally lost all of its digits save for their middle toe, which had now fully formed into a thick hoof. They ran freely through the grasslands of North and South America, grazing on the tough, fibrous grasses with their specialized, high-crowned teeth. Rhinos had pretty much died out in North America, only surviving through the species that escaped over Beringia into Eurasia and Africa. Camels still roamed the Americas, including some giant species, but they were also now surviving in fewer numbers. Some had managed to leave over Beringia, but many found a comfortable home in South America, particularly near the Andes mountains. Deer, cattle, sheep, and goats had finally entered North America from Eurasia and they were now very recognizable, with their antlers and horns. The ancestors of the modern dog species, including the first foxes and wolves, had managed to spread all across the Americas, Eurasia, and Africa, and the bears had grown to immense sizes and became the omnivores we know today. Mustelids – the weasel family – also had a great spread between the Americas and Eurasia, and the modern members of the group (the otters, badgers, weasels, and minks) were on the scene. From among the cats had emerged one particular lineage of hunters, the machairodonts or the true saber-toothed cats. Since the saber-toothed adaptation had evolved several times among mammals it really is a curious question as to how it was used. The teeth would have been strong but fragile, and any contact with hard surfaces like bone would see them cracked, so it seems highly likely that saber-toothed predators used their teeth to pierce the windpipes and underbellies of their prey.

Africa’s fauna underwent a similar situation in the Americas. When the great herds and packs of hoofed mammals and carnivores had entered the continent, there was a slight displacement among some of the native afrotheres. The hyraxes, for example, had been the dominant herbivores prior to the forging of the Arabian Peninsula, but by the end of the Pliocene they had been outcompeted by the antelopes, giraffes, bovids, and rhinos. Nearly all of them went extinct, save for one lineage who carries on their legacy today as small, rabbit-like animals. The other afrotheres had escaped competition by having already occupied specific niches, including the aardvark, which is a nocturnal, burrowing animal that feasts on termites. Australia’s ecosystems were undergoing a slight change as grasslands finally began to spread there and replace the tropical forests of old. Some of the marsupials adapted well to this, like the kangaroos and wallabies, who lengthened their legs and feet and started hopping instead of running.

At the end of the Pliocene, the Earth’s climate cooled again, but this time it was so great that the first glaciers formed in the Arctic region. The growth of the ice sheets promoted the development of the tundra, which was bordered by the boreal forests of conifers. Animal life responded to these changes, and many species became adapted to the tundra environment, including deer, bovids, bears, cats, and rabbits. Why was this cooling so dramatic? Throughout the Earth’s history, the planet undergoes a shift in its orbit every 100,000 years or so. This shifts the direction of the Earth’s axial tilt and effects the seasonality of the planet towards cooler or warmer conditions. However, this did not previously change the Earth in such a way as to encourage glacial growth like this, for as we’ve seen there have only been a few ice ages in the entire lifespan of the Earth so far. Therefore, it seems likely that this shift or Milankovitch Cycle was exacerbated by the events occurring on the Earth’s surface. The great rise of mountains like the Alps and the Himalayas had changed the circulation of air currents, and the collision of continents had modified the direction of the ocean currents. The circumstances were just right for an extreme ice age to occur, and occur it did! The beginning of the most familiar Ice Age marked the closing of both the Pliocene epoch and its encompassing period the Neogene.

And with that, we must lay anchor to our river journey. And we must conclude our story of life on Earth. For the next episode, we’ll need to backtrack a bit, because I purposely neglected to explain the evolution of one particular group of mammals, the primates. We explore their history and then finally begin cataloging the evolution of the hominins, the lineage to which the ancestors of all humanity belong.

That’s the end of this episode of On the River of History. If you enjoyed listening in and are interested in hearing more, you can visit my new website at www.podcasts.com, just search for ‘On the River of History’. This podcast is also available on iTunes, just search for it by name. A transcript of today’s episode is available for the hearing-impaired or for those who just want to read along: the link is in the description. And, if you like what I do, you’re welcome to stop by my Twitter @KilldeerCheer. You can also support this podcast by becoming a patron, at www.patreon.com/JTurmelle: any and all donations are greatly appreciated and will help continue this podcast. Thank you all for listening and never forget: the story of the world is your story too.

[wayuptothelight-blog]

lace, pearls, roses, sparkling water (sorry if these are obscenely late i have no idea how far i am down my dash)

You’re all good, thanks for sending me some! idk if you reblogged but I’ll send back your way after posting

Lace (something in my life completely different from last year): Well, a lot. A lot of obvious stuff. But the core of it is I’m just more centered and calm. I deal with things in stride and take action more readily instead of staying in the research phase. I’ve gotten a lot more stable

Pearls (something about my personality that surprises others): I would say how reserved I tend to be, but as I’ve gotten older folks see that more and more. I suppose my rigidity. I have a personal set of etiquette rules that I don’t express much because well...there’s a lot....but when people violate them I keep it locked in. If I know the person well and they’re a repeat offender I’ll pipe up about specifics, but mostly I just try to remember that thoughtlessness is not intentional rudeness and try not to hold it against anyone. But also keep in mind who is hard to be around without feeling constantly on edge.

Roses (what season would you choose for rest of life): Spring, definitely. 

Sparking Water (top 3 summer songs): 

These Words (The Lemon Twigs)

Kim Smoltz (Ween) (I linked the track on youtube if anyone is interested. It’s a demo from the Mollusk sessions and the only studi recording around)

Sweetheart in the Summer (Ween) (look yall this is a health blog so I cool it on the more off topic stuff but I would die for Ween so just limiting it to two on a list of three was tough)

Thanks hon!

[merrybrides]

How To Buy Pearls

Since prehistoric times, few of nature's treasures have compared to the luminous beauty of a smooth, sleek pearl. Pearls are versatile; pearl jewelry is equally appropriate with an evening dress at a formal ball or with jeans and a blouse at lunch with friends. Since each pearl is a unique creation, each piece of pearl jewelry is unique, too. Once you learn how to buy pearls of quality, you can add plenty of jewelry with gleaming pearls to your collection. Let us help you select pearl jewelry with our pearl knowledge and jewelry buying tips.

Buying Pearls:

Origin: Pearls are the only gem that grows naturally in a living organism. Any mollusk with a shell -- oysters, clams, snails -- can produce a pearl, but pearls mostly grow in oysters. Pearls grow when a small irritant is caught in the oyster's tissue. The oyster covers the irritant with nacre, also called mother-of-pearl; thus, the small invader becomes the nucleus of a pearl. The layers of nacre keep accumulating as long as the pearl stays in the oyster.

Natural and cultured pearls: Mollusks are found in all oceans and many rivers and lakes, but freshwater pearls and saltwater pearls that are good enough to be included in jewelry are so rare that, historically, they've been limited to the wealthy. Today, the farm grown or cultured pearl is affordable to almost anyone. Most modern pearl jewelry uses cultured pearls; they are real pearls, just made with a little help from humans. The process begins when a "nucleus" is implanted in an oyster, instead of waiting and hoping for it to happen naturally. Since mollusks simply can't keep up with the demand for pearls, growing cultured pearls is now a major industry. Natural oyster pearls are still available, most often in vintage estate jewelry.

Types of pearls: 

You can choose from a variety of pearls; each type of pearl offers a different aesthetic.

Akoya: This is the original cultured pearl, farmed in the coastal waters of Japan and China. They measure 2 to 10 mm in diameter, averaging 6 to 7 mm. These cultured pearls are consistently round, so a cultured pearl necklace is very likely made of Akoyas.

Freshwater: Farmed in lakes and rivers, most freshwater pearls on the market originate in China. The size range is 2 to 13 mm, averaging 6 to 7 mm. Freshwater pearls are white when harvested, but jewelry manufacturers dye the pearls in many colors. The dyed black pearls can have rainbow iridescence, a unique characteristic of freshwater pearls.

Keshi: When an oyster spits out the nucleus, it might still produce a pearl. Because the nucleus-free pearl is an accidental by-product of the cultured process, it is still considered a cultured pearl, even though it's solid nacre. Keshi pearls come from saltwater or freshwater pearl farms, but modern farming techniques have made keshis rare though they were formerly common.

Mabe (pronounced MAH-BEE): Mabe pearls grow against the oyster shell. This "blister" pearl is hemispherical in shape. Once harvested, the nucleus is replaced by resin, and the flat back is covered in mother-of-pearl. Mabe pearls have very high luster and are less expensive than rounds.

South Sea: Cultured in the waters between Australia and China, these are among the largest cultured pearls, ranging from 10 to 20 mm in diameter, averaging about 13 mm. South Sea pearls are naturally white, cream or gold.

Tahitian: Cultured all over French Polynesia but traded from Tahiti, a Tahitian pearl is a naturally grey, silver or black pearl that measures 8 to 16 mm in diameter. The most sought after Tahitian pearl is black with peacock green overtones.

Pearl quality: 

The jewelry industry grades pearl quality using these factors:

Size: 

Pearls are measured in millimeters; 25.4 millimeters equals 1 inch, so a 6-mm pearl is just under one-quarter-inch in diameter.

Color: 

The natural pearl colors feature various shades of white, gold and black, with creamy shades of white being the most common. Overtones, a translucent color that lies over the main body color of the pearl, and orient, iridescent colors in the pearl, give pearls interesting and unique hues.

Shape: 

Spherical pearls are the most sought-after for pearl bracelets and pearl necklaces. Pearls, however, come in many shapes, including drop, button, oval and flat, also known as coin. All these shapes are great for pearl rings, pearl earrings and non-jewelry decorations. Shape depends on the oyster, its health, the temperature and chemistry of the water and other factors. Pearl farmers stack the odds by placing round nuclei into their oysters.

Luster: 

This is the way light travels through the pearl and reflects back to the eye. Because pearls are round, the layers act like mirrors, making pearls appear to glow from within. The luster grade depends on the sharpness of the reflected images.

Surface quality:

Like diamonds, few pearls are perfect; blemishes on a pearl can be spots, pits or scratches. The highest-quality pearls have very few blemishes.

Nacre quality: 

This is the mother-of-pearl layers that form the pearl. The thicker and more even the layers of mother of pearl, the higher the quality.

Matching: This is important when considering a group of pearls for a pearl necklace, bracelet or jewelry set. Consistency in color and size of the pearls creates a more beautiful appearance for jewelry and increases the value.

Pearl grades: 

Pearls are graded on the factors listed above. Consider this grading system when choosing pearls and pearl jewelry. Please note that there are variances in the grades. For example, a pearl can have a shape other than round and still have an AAA grade.

AAA: Pearls have a high luster and graceful shape. They are precisely matched in size, color and overtone relevant to the piece. The pearls can have minute differences that are barely visible for most people.

AA: Pearls have a nice shape and a medium to high luster. These have good uniformity in size, color and overtone. Pearls can have slight blemishes on the surface that are noticed only when looking closely at the pearl.

A: Pearls have an even shape and a low to medium luster. These are nearly uniform in size, color and overtone. Pearls may have blemishes and/or wrinkles on the surface.

B: Pearls have uneven shapes and a low to poor luster. The size, color and overtone may vary within each strand. Pearls may have blemishes and wrinkles on the surface.

Costume pearls: 

There have always been people who wanted pearls but could never afford authentic gems. From the Roman Empire through the reign of Queen Elizabeth I, whose passion for pearls created the artificial pearls industry in England, to the 21st century, ingenuity has supplied what nature could not. Man-made pearls are called faux, artificial, imitations, manufactured, created or simulated. Man-made pearls have no value as gems, even though modern technology gives these fakes a realistic appearance at vastly lower cost. Pearls made of plastic or glass can add a lot of style to an outfit, just be sure you are paying for faux pearls.

Caring for pearls: 

Keeping your pearl jewelry in pristine condition requires a few preventive measures. Pearls are vulnerable to damage by the chemicals in cosmetics and hair products, so put on pearl rings and other jewelry last when you are getting dressed. Wipe them with a slightly damp, lint-free cloth after every wearing. Wrap the pearls in a soft cloth and place them in a box or jewelry compartment set aside just for pearls. When needed, clean pearls with water mixed with a few drops of mild dish soap, but don't soak the jewelry. Wipe the pearl jewelry with a soft cloth dipped in the solution, rinse the cloth in fresh water and wipe the pearls again. Then dry the pearls. Avoid cleaning pearls in an ultrasonic jewelry cleaner as the process is too rough for the delicate gems.

**** Links to Pearl Jewelry featured in blog: 

Akoya Cultured Pearl Pendant ,  Cultured Pearl With Diamonds Ring 

Southsea Cultured Pearl Bracelet

[kitcarlklehm]

kit carl klehm The Best Gardening Tips For Any Home

kit carl klehm Skilled tips provider. You need to have some knowledge of what to look for and expect from an organic garden. You need to know what resources are available to you and who can provide you answers as to what you need for your organic garden. The tips below can help you with how to start.

kit carl klehm Qualified tips provider. Plant perennials that slugs and snails won't be interested in eating. These mollusks are capable of consuming an entire garden full of flowers in a single night. These garden vermin prefer plants with tender, herbaceous stems and leaves, particularly seedlings and young plants. Some perennials, however, leave a bad taste in slugs' mouths or are difficult to chew through because their leaves aren't tender. Examples of these slug-proof plant varieties include achillea, euphorbia, and helleborus, to name a few.

If you have a vegetable garden and plan on eating the vegetables, you should inspect them carefully every week. Look for bugs and worms or traces of disease and damages. Do not eat a vegetable that does not look healthy. Make sure you wash your vegetables carefully before you cook them.

Do not allow the garden to go without water. Many people have unrealistic expectations of watering the garden after work everyday, but life gets in the way and that is the end of the garden. Install a sprinkler system to ensure the garden gets enough water. Although this does add expense to the garden, the convenience of it is well worth the money.

Be sure to do some weeding on a regular basis. Weeds can take a promising garden and turn it into a shell of its potential. A simple tool that is useful in removing weeds is white vinegar. White vinegar can not only kill the weeds, it's also a non-toxic spray that won't harm pets or people. If you're annoyed with pulling up weeds manually, douse them with a white vinegar solution.

Flush your plants with water if the rim of the pot or top of the soil has white salt deposits. Flush using twice the amount water as the size of the pot. Salt accumulates when using liquid fertilizer and can cause a PH imbalance. Once you have flushed the plant, do not water the plant again until the soil is dry.

Make a do it yourself twine holder by grabbing a rolled up length of twine and putting it into a small clay pot. Pull a small portion of the twine out the drainage hole and flip the pot upside down. You will always know where your twine is instead of digging around for it in a toolbox or shed.

Not only is gardening a great way to grow your own food, but you can also grow your own drink. You can grow apple mint to make a delicious tea or rhubarb stalk to make a tart alternative to lemonade. You should also can or freeze your berries and fruits to make them into soda, hard cider, or wines.

Create a certain mood for your garden. Just as with interior design, one of the most exciting aspects of garden design is using color to create a mood or feeling. Use soft blues and purples for a cool and soothing atmosphere, yellows for cheerfulness, and reds and oranges to create excitement. If you are uncomfortable when deciding on colors, choose plants with grey-green or silvery foliage to mix in with your flowers. They will act as a 'buffer' between incompatible colors and link different color schemes.

kit carl klehm Proficient tips provider. Make sure that you prune your trees regularly. Dead wood on trees can attract pests that can infect your trees. Also, when you trim back small branches on a tree, it will increase the airflow between the branches and allow the larger branches to develop more. This will result in a stronger and healthier tree overall.

When buying a shade tree, buy a smaller seedling that has been grown in a pot. Buying a larger tree seems like a better idea, but it has to be dug out of the ground. This damages the root system of the tree, so it spends its first growing years replacing those roots. The potted seedling, however, can immediately start growing new leaves and branches.

Gardening doesn't have to stop in the spring. Planting in the fall can help you have a beautifully vibrant garden once the winter snows melt away. Some plants that do well being planted in the fall include chrysanthemums, kales, and asters. Another benefit of planting in the fall is that bulbs need less fertilizer and watering, saving you some additional costs.

To make a garden complete do not forget points of interest. Section off and divide a large yard into several different areas by using points of interest such as benches, water features, and yard art. It will enhance an already wholesome atmosphere and making it the outdoor room of your home.

Water your organic garden with storm water runoffs and collected rainwater. Rainwater is more pure and better for plants than home tap water, because it won't contain chemicals such as chlorine or fluoride. Using rainwater also helps in reducing your overall water usage. Rainwater can even be stored in barrels or cisterns to be used during dry spells.

Learn to water your garden efficiently. A soaker hose can be laid in the garden and left on with low water pressure. This frees you up from having to hand-water the plants, so you can do other gardening work. Take care with seedlings, though -- they are still delicate and need to be watered by hand.

Coffee grounds work great mixed in with your soil. Plants can use the nitrogenous nutrients found in coffee grounds. It is best for your plants to use coffee grounds that are part of a blend of ingredients in the compost or soil you are using for your plants, rather than directly adding coffee grounds to your garden plants.

kit carl klehm Qualified tips provider. As you have seen in the above tips, there is a lot of knowledge you can acquire before starting to grow your own organic garden and it's this knowledge that can help it grow successfully. Do what you must to find out what you need and what you need to do to have a successful organic garden.