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#evolutionary biology
casualcarpetshark · 8 months
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BOW DOWN TO THE ANCIENT ONE
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shitacademicswrite · 8 months
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iamthekaijuking · 5 months
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This just in, starfish are a radially symmetrical head with a stomach.
God I love echinoderms
If you told someone that there’s an entire group of animals that develop butt first as embryos are born bilateral but then grow a radially symmetrical head like a cancer in their side that then bursts out and lives as a completely separate organism from its birth form and moves via hydraulic systems…
They wouldn’t believe you. Yet one of the most beloved cartoon characters is one of them.
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vexwerewolf · 4 months
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Fursuit noses getting damaged by people booping them with cameras led to progressively more reinforced noses, and has now culminated in fursuit noses becoming so rugged they can damage camera lenses
This feels like a demonstration of evolutionary pressure
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mindblowingscience · 10 days
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Small, shelled, and unassuming, chitons have eyes unlike any other creature in the animal kingdom. Some of these marine mollusks have thousands of bulbous little peepers embedded in their segmented shells, all with lenses made of a mineral called aragonite. Although tiny and primitive, these sensory organs called ocelli are thought to be capable of true vision, distinguishing shapes as well as light.
Continue Reading.
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a-dinosaur-a-day · 9 months
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Birds are class Aves.
Sure, under Linnaean taxonomy. But, well,
A) Linnaeus was a eugenecist so his scientific opinions are suspect and his morality is awful
B) he didn't know about evolution
C) he didn't know about prehistoric life
so his classification system? Sucks ass. It doesn't work anymore. It no longer reflects the diversity of life.
Instead, scientists - almost across the board, now - use Clades, or evolutionary relationships. No rankings, no hierarchies, just clades. It allows us to properly place prehistoric life, it removes our reliance on traits (which are almost always arbitrary) in classifying organisms, and allows us to communicate the history of life just by talking about their relationships.
So, for your own edification, here's the full classification of birds as we currently know it, from biggest to smallest:
Biota/Earth-Based Life
Archaeans
Proteoarchaeota
Asgardians (Eukaryomorphans)
Eukaryota (note: Proteobacteria were added to an asgardian Eukaryote to form mitochondria)
Amorphea
Obazoa
Opisthokonts
Holozoa
Filozoa
Choanozoa
Metazoa (Animals)
ParaHoxozoa (Hox genes show up)
Planulozoa
Bilateria (all bilateran animals)
Nephrozoa
Deuterostomia (Deuterostomes)
Chordata (Chordates)
Olfactores
Vertebrata (Vertebrates)
Gnathostomata (Jawed Vertebrates)
Eugnathostomata
Osteichthyes (Bony Vertebrates)
Sarcopterygii (Lobe-Finned Fish)
Rhipidistia
Tetrapodomorpha
Eotetrapodiformes
Elpistostegalia
Stegocephalia
Tetrapoda (Tetrapods)
Reptiliomorpha
Amniota (animals that lay amniotic eggs, or evolved from ones that did)
Sauropsida/Reptilia (reptiles sensu lato)
Eureptilia
Diapsida
Neodiapsida
Sauria (reptiles sensu stricto)
Archelosauria
Archosauromorpha
Crocopoda
Archosauriformes
Eucrocopoda
Crurotarsi
Archosauria
Avemetatarsalia (Bird-line Archosaurs, birds sensu lato)
Ornithodira (Appearance of feathers, warm bloodedness)
Dinosauromorpha
Dinosauriformes
Dracohors
Dinosauria (fully upright posture; All Dinosaurs)
Saurischia (bird like bones & lungs)
Eusaurischia
Theropoda (permanently bipedal group)
Neotheropoda
Averostra
Tetanurae
Orionides
Avetheropoda
Coelurosauria
Tyrannoraptora
Maniraptoromorpha
Neocoelurosauria
Maniraptoriformes (feathered wings on arms)
Maniraptora
Pennaraptora
Paraves (fully sized winges, probable flighted ancestor)
Avialae
Avebrevicauda
Pygostylia (bird tails)
Ornithothoraces
Euornithes (wing configuration like modern birds)
Ornithuromorpha
Ornithurae
Neornithes (modern birds, with fully modern bird beaks)
idk if this was a gotcha, trying to be helpful, or genuine confusion, but here you go.
all of this, ftr, is on wikipedia, and you could have looked it up yourself.
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My mom bought me this book for Christmas
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The Resurrectionist by EB Hudspeth, a fantasy field guide full of anatomical illustrations of monsters and cryptids.
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The musculoskeletal systems are fun to look at, but not nearly as in-depth as I would have liked. If you have more than a passing knowledge of taxonomy (or in my case, access to Wikipedia), a lot of the details fall apart under scrutiny
The harpy has four upper limbs connected to one shoulder girdle; it shouldn't have arms, only wings
The sphinx is not classified as a mammal, but is still somehow in the family Felidae with cats (and like the harpy is also drawn with only two girdles despite having six limbs. I will give the author credit for giving the sphinx a keel for the wing muscles to attach to)
It lists the Hindu deity Genesha as a cryptid, which is a no-no.
Cerberus is also explicitly not a mammal, but somehow still a canine (literally in the species Canis with wolves, dogs, and coyotes)
Both mermaids and dragons are listed as members of the order Caudata; the only extant members of Caudata are salamanders, which kinda makes sense for dragons, but not so much for mermaids (also, the author keeps playing it fast and loose with cladistics; both mermaids and dragons are in the same order despite being in different classes, and while dragons are explicitly said to be amphibians, mermaids are given the fictional class mammicthyes, which means mammal-fish. At that point, why not just call mermaids amphibians? Why make up a fake latin hybrid name?)
But what bugs me most of all is the classification of the Minotaur as its own order of mammal when in mythology it is explicitly described as a hybrid of two known species (made possible only by the cruel machinations of the divine, but still)
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To use actual taxonomical nomenclature, the minotaur's species would be B. taurus × H. sapiens (specifically B. taurus♂ × H. sapiens♀; there are, to my knowledge, no legends of H. sapiens♂ × B. taurus♀). That's how ligers, tigons, mules, zorses, pizzly bears, narlugas, etc., are described.
If I had written this book, I would have leaned more into evolutionary biology. Most land animals have four limbs because they all evolved from boney lobe-finned fish, which split off from the boneless sharks and rays millions of years earlier, so any six-limbed vertebrates would need to be descended from a fictitious category of six-finned fish which would either be an offshoot of boney fish/tetrapods (I guess they'd be hexapods, though that term refers to insect arthropods), OR a precursor to boney and cartilaginous fish that both clades split away from much earlier (it's easier to lose structures than to gain them, so it makes more sense for a six-limbed ancestor to spawn four-limbed descendants than the other way around).
Think about how different elephants are from humans, and humans are from aligators, and aligators are from penguins, and remember that they all evolved from the same ancestor tiktaalik, an amphibious fish that existed some 375 million years ago. Imagine a precursor six-limbed species and how diverse all its descendants would look after 400 million years. Save for the occasional instance of convergent evolution causing two unrelated species to independently evolve similar body plans to fill the same niche, tetrapods and hexapods would look nothing alike. There would be very little recognizable overlap between the two. A six-limbed "pegasus" would not look like a real world horse, and a six-limbed "dragon" would not look reptilian/dinosaur-ish, for much the same reason that giraffes don't look like frogs; they're just too distantly related. Bonless sharks and boney fish and whales/dolphins all have similar looking bodyplans only because their environment requires the same hydrodynamic shape, while terrstrial vertebrates are much more physically diverse.
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bootleg-nessie · 9 days
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Predatory Bananas: an Evolutionary Horror
(Pls read, I literally spent HOURS on this <3)
A friend sent me the following video about the various potential methods of banana locomotion. It got me thinking. How would a banana move? Naturally, as an autist with a special interest in evolutionary biology, I took the joke a little too far and wrote a whole piece on the matter, analyzing the feasibility of each method and the changes they’d need to evolve in order to achieve them.
(Video courtesy of Burning Onion Animation on TikTok, they make great content, go check them out)
The first and most likely way bananas would move is if banana trees evolved to spread their seeds through their fruits rolling down hills like the morphology of #1 suggests. The only major mutations that need to happen are a more pronounced curve and increased rigidity to facilitate rolling and absorb the impact from falling from the tree. Overall, evolving to this point is relatively straightforward. #1 is the most feasible and realistic answer.
For bananas to develop motility like in #4 is theoretically possible with the right environmental pressures and with enough time, though much more difficult. I see this working in one of two ways. First, they could evolve rigid structures that change shape depending on moisture content, using natural dry/wet cycles to move a little more each time it rains, much like the seeds of Erodium Cicutarium (pictured below). The fruits of the banana tree would most likely evolve to have hooks on the end of said structures, contracting and pulling themselves forward a little each time they dry out, and relaxing and resetting their grip on the soil each time they get wet.
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The second way I could see this happening is if they evolved true locomotion. True locomotion in bananas would take at least a few million years to evolve (probably more like tens of millions), and even then, movement would be incredibly slow. There exists a plant called the “walking palm” (socratea exorrhiza, pictured below) that’s capable of “walking” using its roots, but it can only travel about 20 meters per year in ideal conditions, and has the resources of the entire tree at its disposal, not just that of a single fruit.
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While this is the more likely explanation as to how #4 might happen, it’s not what the video depicts. The video clearly shows a banana dragging itself along like an inchworm, indicating motor cells such as those present in Dionaea Muscipula (venus flytrap, pictured below). Whenever this type of movement in plants occurs, it takes an extreme amount of energy and is generally rather inefficient and slow. In addition to this, the banana is moving its entire mass every time, so it’ll have to move much more slowly to compensate. This means that the banana would probably only be able to travel a few centimeters before decomposing beyond the point of functionality. After a few million more years it’s possible that bananas could evolve to travel as far as several meters after falling off the tree, but the further they go, the more fit each individual fruit needs to be, and the more energy and resources they need. Eventually, it’ll reach a point where the energy expenditure will outweigh the benefit and the fruits will stop evolving to travel any further, which I imagine would plateau somewhere in the 0.5 to 3 meter range. However, the fruits still require a significantly higher amount of energy at this point because they’ve evolved to move autonomously, so trees would likely evolve to produce fewer, but more developed fruits as a result. Overall this is the second most likely way bananas would evolve to move, but the video depicts a time lapse, not footage taken in real time.
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The next most likely option is #2, which is where things start to get much more interesting. At this point we are quickly beginning to leave the territory of the banana being a fruit and stepping closer towards the realm of the banana being its own independent organism. Whether the banana is still a single fruit from a larger tree depends on if the video is stabilized or not. First, let’s assume that the video has automatically stabilized the banana within the frame. This means that the banana is moving erratically and aimlessly, with the goal of simply moving as far from its origin as it can. The most simple form of this would be a ballistic dispersal method in which the banana grows curved and under tension, falling off the tree when ripe. Upon impact, the tension is released and banana extends, springing itself upward and outward with a single bounce. But this isn’t what the video shows either, it depicts clear and repeated movement, again suggesting the presence of motor cells much like those likely found in banana #4. In this case it probably evolved in roughly the same way as banana #4, but works less effectively due to having a less stable method of traveling.
But what if the video ISN’T stabilized, and the banana’s staying upright all on its own? In the video, the banana isn’t just moving along a single plane with one set of motor cells like the Venus flytrap. It’s full on galloping. This requires multiple groups of motor cells working together in a coordinated effort. This banana has real-time sensory input to orient and stabilize itself. This means that the banana has evolved some sort of internal gyroscope, much like our inner ear that helps it determine what up and down is, and more importantly, angular rotation. While plants have been observed reacting to and even predicting stimuli in ways that still baffle scientists to this day, this is far more complex than any plant every discovered throughout human history. Everything here points to something more, perhaps rudimentary intelligence, dare I even say sentience.
This begs the question: is it even a plant anymore? At this stage it’s evolved sensory organs and can move independently. But why? Organisms don’t evolve the ability to move without reason. This could mean one of three things. First, it could have evolved the ability to run as a means of spreading its seeds further. But this can’t be the answer. Moving more slowly would be way more efficient for a banana in terms of energy expenditure, and spreading seeds the old fashioned way is still perfectly viable, so it wouldn’t have evolved that way due to lack of necessity. This brings us to the first legitimate possibility: the banana is prey. If the banana were prey, then the ability to gallop most likely evolved as a means of escaping predators and to avoid being eaten. This is further evidence that the banana has evolved beyond being a humble plant as this goes completely against the purpose of fruits, which evolved to be eaten on purpose. Now, the banana’s goal isn’t to be eaten so that its seeds may be deposited elsewhere, its primary objective is to survive. At this point it’s relatively safe to assume that the banana no longer comes from a tree, and now reproduces through fragmentation, or perhaps even live birth. Its lack of leaves suggest that it’s evolved beyond being an autotroph and relying on photosynthesis. But if it no longer gets nutrients from a tree, how does it subsist? It must be getting its energy from somewhere. The most likely answer to this is that banana is a herbivore, and gets its energy from plant matter, which contains a lot of the same nutrients that the banana recently used to get by growing on a tree. Overall, this is the third most likely way the banana would evolve locomotion.
But what if it isn’t an herbivore? This brings us to the other possibility: the banana is a predator. The banana that concerns me the most is banana #3. While all the other bananas have undergone major changes to their morphology, banana #3 appears to be identical to any regular banana, yet it still moves. The only way that such movement could be possible is if the banana had some sort of internal mechanism that moves its center of mass around rather quickly within its outer shell, which also requires an internal gyroscope for balance. I know what you’re thinking; “but this is an incredibly complex mechanism, wouldn’t it be easier to evolve one of the other ways?” To which the answer is yes, it would. But this raises another question with an even more alarming answer: why didn’t it? The answer lies in the banana’s identical appearance to that of a typical Cavendish. Clearly, looking like an ordinary banana is central to its survival strategy. At this point, it’s evolved well past the point of being a fruit and has become the first of an entirely new kingdom of sentient creatures descended from plants.
According to my estimates from the video, banana #3 is only able to move at a pace of around a tenth of a meter per second, maybe a quarter or half of a meter at the most. This means that it probably didn’t evolve the ability to move as a means of running from predators. Based on the physics in the video, my best guess as to how the banana moves is through the use of mostly hollow internal chambers with a central mass (probably a calcified seed) suspended by tendons that can move in any direction, accelerating the banana in that direction. Here I’ve collaborated with the massively talented @pholidia to bring my ideas to light.
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Picture it. You’re a lone banana farmer in South America. You’re out harvesting your crops when you see a single banana on the ground. It looks a little weird and bruised, but still totally edible. “No good in letting perfectly good produce go to waste” you think to yourself as you pick up the banana. You go to peel it when suddenly, you feel a sharp shooting pain through your hand. You drop the banana, then fall to your knees. You look around for the wasp or whatever it was that stung you, but you can’t find anything. You collapse in a heap on the ground, unable to control your body. It’s at this point you notice the banana start to move. “Are… are those teeth?” you think to yourself. At this point the venom has taken full effect. You are alone and completely paralyzed, unable to do anything besides observe the banana as it starts moving towards you. Sharp teeth and beady black eyes are fully visible now. It ambles towards you clumsily, moving almost as if it were being controlled by invisible strings like a marionette. It reaches you and starts to chew. It is at this moment that you discover, much to your horror, that the venom is merely a paralytic, and not an anesthetic. Helpless to the venom, you can do nothing but watch as your blood slowly drains out onto the ground as the creature consumes you. Slowly, your vision begins to fade to black. You pass out, either from the pain or the blood loss, you’re not really too sure. You take one last look at the creature, then you’re gone forever.
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froggerworld · 6 months
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hi guyss :) im studying supernatural belief, religious belief, locus of control, and their relationship to evolutionary sex differences for my master's thesis!! i'd grately appreciate if yall can complete and share this survey:
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hotwifeky1 · 3 months
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Alpha Males, Sperm competition, and Cuckoldry
(our kinks from an evolutionary biology perspective)
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The phenomenon where males experience an increase in desire and fertility when observing their mate engaging with another partner, is often referred to as "sperm competition risk"
From an evolutionary biology perspective, this behavior can be understood through several theories:
Sperm Competition Risk:
Increased Ejaculate Volume: Males typically respond to the perceived risk of sperm competition by greatly increasing the volume of their ejaculate. This is thought to function as a form of displacement, increasing the chances of their sperm outcompeting that of potential rivals.
Increased Sexual Arousal and Fertility: 
When males perceive or observe their partner with another mate, particularly when chance of sperm competition exist (other males trying to fertilize the same egg), this triggers an adaptive response in the form of greatly increased sexual arousal, desire and fertility. This is thought to be an adaptation to compete effectively in situations where multiple males are vying for the opportunity to father offspring. 
Potential benefits
From an evolutionary perspective, the heightened desire, arousal, focus, and drive provide a large competitive advantage. If there's a chance of sperm competition, being sexually impassioned increases the likelihood of the observing male's sperm fertilizing the egg. The continuous denial of sexual interaction further amplifies these benefits. By maintaining a state of heightened desire without immediate release, the observing male sustains an elevated level of reproductive readiness. This prolonged state of arousal becomes an advantageous strategy, potentially increasing the male's chances of success not only in reproduction but also in various aspects of everyday life. The surplus of energy, focus, and drive may contribute to success across different domains, aligning with the overarching goal of evolutionary fitness.
Cuckoldry Detection and Response:
Adaptive Jealousy: 
Evolutionary psychology suggests that males who exhibit jealousy and distress over potential infidelity may have had a reproductive advantage. 
This emotional response acts as a mechanism to deter a mate from engaging with other males, reducing the risk of cuckoldry. 
The cuckold male may also gather information by observing the mating behaviors of potential rivals. This is thought to be an adaptive strategy to understand the competition and adjust his own behaviors accordingly.
Paternal Investment: 
In species where males invest significantly in parenting, there is an evolved response to protect their paternal investment. The greatly Increased arousal along with increased romantic and sexual interest in response to perceived mate infidelity is a strategy to safeguard resources and parental care for their own genetic offspring.
The alpha male typically refers to a dominant and high-status male in a social group. The alpha male generally has preferential access to mates and reproductive opportunities.
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Alpha Male Cuckoldry reproductive strategy:
Within the context of cuckoldry, the alpha male strategically reserves exclusive access to mates. Cuckoldry occurs when the non-dominant male knowingly or unknowingly raises offspring that do not carry his genetic material. 
This reproductive strategy is advantageous for the both the alpha male and his mate, allowing him to pass on his own genes while minimizing resource-intensive parental duties. The female benefits by mating with a genetically superior male while sharing parental responsibilities with the non-dominant male.
By ensuring that the non-dominant male invests in raising offspring that carry the alpha male's genetic legacy, this reproductive approach aligns with the collective goal of the female and alpha male, maximizing his reproductive success within the social structure. The alpha male's dominance and preferential access to mates become central elements in shaping the dynamics of cuckoldry as an evolutionary strategy.
Often, the non-dominant male, in his role, finds personal satisfaction in having his sexual and reproductive desires denied as he plays a crucial part in perpetuating the genetic lineage of the dominant alpha male rather than his own.
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cbsorgeartworks · 12 days
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I don't know what I'm doing anymore lol. Getting back into paleo stuff. Tiktaalik feelings. I plan on making this into a small edition of 2 color screen prints on paper, so follow along to get notified for that! Photoshop // ~ 8 hours
Instagram // X // Bluesky
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bi-krama-dick-ya · 10 months
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bethanythebogwitch · 8 months
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The modern world is nice, but sometimes you just get the urge to go primitive. Because I'm a complete wimp who would die within a day of giving up the internet, I'm going to deal with that urge by talking about primitive animals. It's Wet Beast Wednesday and I'm talking about lancelets.
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(image: a lancelet. Not much to look at, are they?)
Lancelets, or amphioxi, are highly basal (close to the ancestral form) chordates that are vaguely similar to fish, but are vastly more primitive. They have all the characteristics of chordates, the key one being a notochord, a flexible rodlike structure that goes down the body. The majority of chordates that are still alive are vertebrates, who have incorporated the notochord into the spinal column. The other groups of surviving chordates are the tunicates (who I'll get to eventually) and the lancelets. Because lancelets are so primitive, they are used at model organisms representing an early stage of vertebrate evolution. It was originally thought that lancelets are remnants of an early lineage that eventually evolved into vertebrates. Genetic studies later showed that tunicates are actually more closely related to modern vertebrates than lancelets. They are still used as a model organism as they are a fantastic representation of early chordates. The similarity of lancelets to the 530 million year old Pikaia gracilens, one of the earliest known chordates, is one of the reasons they are such a useful model organism.
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(image: a diagram of lancelet anatomy by Wikipedia user Systematicist)
Lancelets can be found all over the world, living in temperate to tropical shallow seas. The only known exception is Asymmetron inferum, which has been found around whale falls at 225 m (738 ft) deep. They are small animals, reaching around 8 cm at their largest. An amphioxus looks pretty worm-like, with a simple mouth at one end and a pointed tail at the other. The name amphioxus means "both (ends) pointed" which is a pretty appropriate description. The mouth is lined with tentacle-like threads called oral cilli, which are used for feeding. Lancelets are filter-feeders that use the cirri to filter plankton, microbes, and organic detritus. Water and food pass into the pharynx (back of the mouth), which is line with gill slits. This is where it gets weird. The gill slits aren't used for respiration, but for feeding. Mucus gets pushed through the gill slits by cilia, trapping the food and moving it deeper into the digestive tract. Not only to lancelets not use their gill slits to respirate, they actually don't have a respiratory system at all. Instead, they just absorb dissolved oxygen through their thin and simple layer of skin. Their circulatory system doesn't move oxygen around either as there is no heart or hemoglobin present. For what it's worth, they don't have a proper live either. When you look at a lancelet's anatomy, you can see similarities to fish anatomy, just much more primitive and with some parts missing.
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(image: the head of a lancelet, with mouth and cilli visible)
Lancelets have 4 different systems used for vision. Two, the Joseph cells and Hesse organs, are simple photoreceptors that are on the notochord and detect light along the back of the animal. Imagine having a bunch of very simple yes on your spinal cord that can see through your skin. There is also a simple photoreceptor called the lamellar body (which confusingly is also the name of a type of lipid) and a single simple eye on the head. Speaking of light, lancelets are florescent, producing green light when exposed to blue to ultraviolet light. In all species, the proteins responsible for this are found around the cilii and eye, but some species also have them in the gonads and tail. The purpose for this florescence isn't exactly known, but a common hypothesis is that it helps attract plankton toward their mouths.
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(image: an extreme close-up of a lancelet's cilli fluorescing)
Lancelets have seasonal reproduction cycles that occur in summer. Females release their eggs first, followed my males releasing sperm to fertilize them. Depending on species, spawning can either occur at specific times, or gradually throughout breeding season. Development occurs in several stages. In the frist stage, they live in the substrate, but they will quickly move into the water column to become swimmers. These swimming larvae practice diel vertical migration, traveling to the surface at night and returning to the seafloor in the day. While larvae can swim, they are still subject to the current and can be carried long distances. Adults retain their ability to swim, which is done by wriggling like an eel and in some cases, spinning around in a spiral fashion while moving forward. Unlike the larvae, adults spend most of their time buried in the substrate with only their heads exposed. They typically only emerge when mating or if disturbed.
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(image: a diagram of the lancelet life cycle. source)
Because of their use as model organisms, humans have developed methods to keep and breed lancelets in captivity. The majority of research has been done on Branchiostoma lanceolatum, but several other species have been studied. Multiple species are endangered due to pollution and global warming. Several species are edible and can either be eaten whole or used as a food additive. In spring, when their gonads begin to develop for breeding season, they develop a bad flavor.
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Mom: "we have garden eels at home". Garden eels at home:
(image: three lancelets sticking their heads out of the sediment)
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forms-and-phyla · 9 months
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Phylum #11: Priapulida, the penis worms!
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It is the late Ediacaran. For thirty million years, enigmatic creatures have peacefully grazed on microbial mats - unique ecosystems where layers of photosynthetic bacteria covered the shallow seafloor. And then the penis worms arrived.
Priapulids were among the first animals to start digging inside the substrate at a large scale. Unlike previous creatures, their burrows were vertical, not horizontal. Disturbing the microbial mats in depth and oxygenating the substrate, they set the stage for life to diversify in a new ecosystem. The Cambrian substrate revolution had begun.
530 million years later, priapulids - named after the Greek god of fertility - survive as one of the three scalidophoran phyla. The only ones to still reach massive sizes, some species can be up to 40 centimeters long!
While they do not have plated armor or complex spines like their cousins, they share the ability to extend and retract their spiked head. They also live in or near the seafloor, often hunting for sea worms which they catch with their toothed, eversible pharynx. Their body often ends in complex tail appendages, believed to act as gills thanks to their large surface area.
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rosayenem · 3 months
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What of the possibilities that are not adaptive for the system, in part or as a whole
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a-dinosaur-a-day · 7 months
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So we don't know, exactly, how most birds are related to each other
so, for fun:
more polls that can't get derailed
had to cut the et al for space, sorry
enjoy
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