#through alligator and croc studies

[nico-moist-moses]

Guess who just learned how to draw crocodilian anthros! Ill post a fuller rendition later. for now, ~sneak peak~

[a-dinosaur-a-day]

correct me if im wrong, but is a cxrocodile and alligator a type of dinosaur, that stayed the same through millions of years

not even a little bit to either

dinosaurs are defined as the most recent common ancestor of [Theropods] + [Sauropodomorphs] + [Ornithischians] and all of that ancestor's descendants. that includes all living birds. however, crocodilians fall outside of it

in fact, the group ruling reptiles (archosaurs) is divisible into two halves: crocs and their relatives; and birds and their relatives.

all dinosaurs are on the bird half.

furthermore, crocodilians have gone through a LOT of evolution over Earth's history and have occupied a very diverse range of niches. Modern crocodilians are actually much less disparate than they used to be.

In addition to that, multiple studies have indicated that organisms that maintain the plesiomorphic condition (ie look the same over time or seem "primitive" or "basal") go through more genetic evolution because they experience the same amount of genetic drift as populations that are more obviously changing, because they need to correct for that genetic drift into non-tenable niches

ie Palaeognaths (ostriches et al) have had more change on the genomic level than Neognaths (literally all other birds) even though they look a lot like nonavian dinosaurs (specifically ornithomimosaurs)

don't even get me started on how much sharks have changed

[is-the-snake-video-cute]

aaa it's the croc anon! (sending again since tumblr is buggy for me) thank you for the info :D im currently practicing on drawing/writing abt crocs/gators and i like to research n pick up tidbits of info to better understand.

you mentioned that them closing their eyes is akin to a grimace and i wanted to know if there was a reason why that is? :0 because usually sight is important in the wild, or is it bc they're the usual apex predators in their system?

feel free to add more fun facts too! :D they're such cool reptiles and i feel like ppl need to know more abt them, like how they can be in such cool colors of orange/blue/black, instead of the standard green!!

That's a really good question! It definitely seems counterintuitive, huh?

Closing the eyes when stressed is very common among reptiles! You'll see lizards doing it, too. When upset reptiles close their eyes to communicate discomfort, they're almost always doing it when they feel harassed by a bigger animal (like us). Eye contact is often a confrontational thing in the animal world, so it's kind of a way for them to communicate that they're not a threat, they don't want any trouble, and they just want to be left alone.

Here are some cool crocodilian facts! (Frankly, we don't talk about them enough on this blog...)

The smallest crocodilian in the world is the Cuvier's dwarf caiman. They're way smaller than crocodiles or alligators, but still about the size of a medium dog.

In contrast, the saltwater crocodile is both the largest crocodilian and the largest living reptile. They can grow over 20 feet long and weigh over 2000 pounds!

Crocodilians eat mostly meat, and they were once thought to be obligate carnivores, but they also seem to enjoy occasional fruits! Recent studies have found that crocodiles will sometimes consume large quantities of fruits.

Crocodiles have the strongest bite force in the world, at about 5000 pounds of pressure per square inch. In comparison, humans sit at about 100 PSI, and great white sharks rank at 500.

Despite this, they have very weak jaw opening muscles. That's why banding them works - you can even hold their jaws shut with your bare hands (don't try that).

Crocodilians are ancient. They've undergone very little change since ancient times - the American alligator, for example, first appeared over 80 million years ago.

Crocodilians replace their teeth regularly as they age. Depending on species, they usually have anywhere between 60-100 teeth at any one time, and will go through thousands during their lifetimes!

[fatehbaz]

The distinctive traits and behaviors of gharials (Gavialis gangeticus) and muggers (Crocodylus palustris) benefit not just themselves, but also the ecosystem in general. For example, fishing communities living in areas where gharial populations have increased have reported improved fish stocks as the crocodiles prey on the big fish that would otherwise feed on their preferred catch species. Similarly, the burrows made by muggers have been found to be used by other animals as well. Griffith says this led her to think about the diversity of the 28 crocodilian species that exist around the world today, and the different ecological roles they play. So she decided to explore it further. 

The results were published recently [4 August 2022] in the journal Functional Ecology, in which Griffith and her colleagues built a global trait database for all existing, or extant, crocodilians. They looked at measurable characteristics linked to how each species functions in its environment, such as skull shape, body size and habitat use, and assigned scores based on the traits that influence one or more aspects of their functioning in the ecosystem and their uniqueness in an evolutionary sense. The team then identified four functional groups of crocodilians that had similar ecological roles. However, the gharial, because of its distinctive ecological functions, stood out and didn’t fit well into any of the groups. [...]

“We used data from the IUCN Red List as well as data from ongoing assessments of crocodilians around the world,” Griffith says. Gharials scored the highest on this new metric, known as EcoDGE, or ecologically distinct and globally endangered, followed by the Chinese alligator (Alligator sinensis), of which fewer 100 are left in the wild.

“We found the gharial was the most functionally distinct species, the species with the most unusual ecological role,” Griffith says. “The loss of the species would mean there’s nothing like gharials in the world today.”

Gharials, known for their long slender snouts that end in a comically bulbous nose, were once abundant in the Ganges River Basin that runs through Nepal and India. Today, they’re limited to a handful of tributaries, and are threatened by fishing, changes in river flow due to dams, and poaching.

Fewer than 200 breeding adults are believed to live in the wild in Nepal. Since 1978, Nepal has run a program to raise gharial hatchlings in captivity, in an effort to boost the wild population. Officials in Chitwan and Bardiya national parks collect eggs from riverbanks, provide a suitable environment for them to hatch in, and feed and raise the young gharials until they’re around 5 years old, at which point they’re released into the wild.

It’s not just gharials and Chinese alligators that are in need of urgent conservation efforts. According to Griffith and her colleagues, 15 of the 28 extant crocodilian species are threatened with extinction. The EcoDGE ranking they developed suggests that conservation of species such as the Orinoco crocodile (Crocodylus intermedius), the Cuban crocodile (Crocodylus rhombifer), the Philippine crocodile (Crocodylus mindorensis) and the Siamese crocodile (Crocodylus siamensis) also need to be prioritized.

---

Headline, images, captions, and all text published by: Abhaya Raj Joshi. “Gharials, most distinctive of crocs, are most in need of protection, study shows.” Mongabay. 25 August 2022.

[rachelcommitscrimes]

some of my smaller interests that you may not have known

- Total Drama (Alejandro is my favorite bc we’re both bilingual and sexy)

- Higurashi (Satoko>>>>)

- Chainsaw Man (I have an unhealthy obsession with Power)

- Neon Genesis Evangelion (its so pretty mmfhnngh)

- Japanese culture/folklore (no i’m not one of those gross asian fetishizers i do research and respectfully study and admire the culture from its ancient time til now)

- Gators and crocs (while american alligators are my favorite I LOVE THEM ALL PLS I COULD TALK ABOUT THEM FOR HOURS)

- KOMODO DRAGONS (OK YALL THIS IS MY FAVORITE ANIMAL IN THE WORLD I LOVE THESE GUYS THEY MAKE MY AUTISM GO THROUGH THE ROOF PLSPLSPLS ASK ME QUESTIONS ABOUT THEM)

- Snakes (i want one so bad, my favorite is the fer dé lance viper in South America)

[blubushie]

I don't know if you've done this before, but I wanna know how you'd order the (canon) mercs from most to least favorite.

Oh, strewth, I haven't done this before!

Sniper, obviously. My skrunkly. I want to make him a warm meal and let him nap for awhile. I'd like to go croc spotting with him. Fishing, too. Take him out to the South Alligator and fish for barramundi. Also discuss sniper shit because it's been a few weeks and I miss it. My sheila can supervise us and make sure we don't end up biffing because when you get two headstrong, competitive blokes together that has a tendency to happen. Also because he has a foot on me and would absolutely kick my arse and probably chuck me overboard for the crocs. She's there for my protection, not his.

Scout. This poor lad has been through so much shit. He deserved a better dad, a better childhood. We could talk baseball. My dad's American (NorCal) so I grew up an SF Giants fan (also an Adelaide Giants fan). Growing up in Alice Springs I'd play baseball with the American kids from Pine Gap and when I went back to the US I played baseball there too, so I know a bit about baseball. I'm sure we could keep each other entertained. I also love music from the 50s-70s so I would sing Tom Jones songs with him.

Spy, the faguette. A cunt for leaving his son but I also understand why he did it. If we were mates I'd nick his darts. I bet he flavours them (and I have a deep affection for rum-flavoured cigarillos). Probably has a nice humidor and everything in his study. I don't even have a humidor. I don't care for wine but I'm keen on discussing liquors with him, especially any whisky and scotch. I'd nick a bottle of Macallan from him when he's not looking and he'd cut my fingers off for it later. We can invite Sniper and Demo for booze tasting. I also want to know what cologne he uses to hide the stink lines.

Medic. Absolute madcunt. He makes me wish I actually ended up going to medical school (Christ, could you imagine me as a doctor?) Upmost respect for his chaos. I want him to crack my skull open and lobotomise me while I'm working. Would let him literally rearrange my guts. He has the level of cunning and improv that I wish I had. Suave cunt that can talk his way out of any situation.

Engineer. A workaholic who never rests. A good ol' southern boy. He reminds me of my older brother. I want to discuss southern shit with him. Unhealthy fried foods, summer fairs, mustering cattle (but he'd call it wrangling). I would kill for him to grill me a steak. I'd love to talk to him about rodeos and cutting horses. I'd love to see him ride a horse. I'd love to race horses with him.

Demoman. Another workaholic who just wants to make his mum proud to the point of his own detriment. His personality reminds me of my mate Jack. Fun-loving with a cocky attitude and pride in what he does and a penchant for explosives. We could have a few beers and exchange ghost and monster stories. My dad went to sniper school in the Marines and was the top of his class but he never got to finish it because he caught malaria, almost died, and by the time he recovered he'd missed his final testing and it was time to ship out. They made him a grenadier, so he'd lugged an M79 grenade launcher through the jungle from 1968 to 1969 when he went home. He loved it. My dad would love to talk bloopers with him.

Heavy. A man who go to hell and back for his family and those he loves. It's not that I don't like him. He just scares me. He could break me in half like a twig. I'd rather swim in the South Alligator than face him on the battlefield. I would love to discuss history and literature with him, though. I hope he could translate classic Russian literature for me.

Pyro. A little maniac with a hot streak. Much like Heavy, Pyro bloody scares me. He gives me the vibes of inviting me to a tea party (which I'd accept) and then cutting off my hand when I refuse sugar. I would constantly be on edge. That said, he'd always have a light, so it can't be too bad.

Soldier. A character I wish we got to see a better side of. I'm sorry! I reckon I just see "stupid military man" too much in media and it kinda stings since 1) the military (both US and AUS) have really high standards for entry, and 2) my dad is a Marine and without doubt the smartest person I've ever met. He taught me to shoot and he was doing the windage calculations in his head. I have to write it down. I can't even do it in my head. He was only trained as a sniper for a few months and I've been doing this for 3 years and he's still better than I could ever hope to be. Yes, I'm aware Soldier wasn't actually in the military, the stigma just... stings, I suppose? For a non-canon deviation, I love what Emesis Blue did with him. Kept his personality without making him a complete dumb cunt. He felt like Soldier but still capable, a complete dumb cunt in personality but still cunning and what you'd expect of a mercenary. "What are you, blind? Come on! Right here! Take your best shot!" -My dad, probably, before he was shot in the head by a Viet Cong sniper.

[carousel-of-souls]

Gotham New Orleans Backstory: Waylon Jones

This is a lot different than the canons but it makes me happy and it’s the direction I felt pulled in.

Warnings: possible body horror, financial insecurity, sexual content, ableism

He’s mixed and before his condition got bad he was fairly pretty. Light brown skin, long dark curls (which he still has because I think it looks cool, there’s enough bald Killer Crocs) and he kept a mustache sometimes but stopped cause people told him it made him look older.

He was an orphan, lived in an orphanage until it shut down due to hazardous materials found in the pipes (surely that isn’t relevant to anything) the government wasn’t public about that being the reason.

He got moved to a different place until he was 18. He didn’t suffer any additional trauma from his experience as an orphan besides being separated from his parents as a baby. Sometimes he wished he had a family but luckily the facilities he was in were good (the first one didn’t know about the hazardous waste being dumped in the swamp nearby) and he stayed in contact with friends who did get adopted.

He had been working and saving money since he was 16 which was good because at 20 he started having skin issues and burned through a lot of his savings trying to get diagnosed. He got diagnosed at 22 with some severe ichthyosis and was able to start taking stuff for it. Once his meds were tweaked a few times his skin mostly cleared up. He didn’t have to pay for part of the treatment because the nature of his condition was something they’d “never seen before” and allowing them to study and treat him was valuable data. Coincidentally a lot of the other people who were at the orphanage that got shut down started having health issues as well.

Waylon wanted to work in TV and managed to land a job as a weatherman for a few years. That was until his condition got bad again. All that happened was the prices for his meds went up and his salary didn’t. Since he wasn’t nice to look at on camera anymore he got fired and couldn’t find another job.

His skin got worse and he was broke so he signed up for a clinical trial at the lab Ivy worked in at the time. That clinical trial turned out to be secret gene splicing and they spliced his dna with a crocodile’s, they were experimenting with crocodiles and alligators already so it had little to do with his scaly skin. They didn’t follow up with him because after Ivy went rogue she released all their test subject animals and burned half the lab down.

Waylon had to start robbing places since he didn’t get paid from that trial and when people saw his appearance they assumed he was one of the rogues, he started getting called Killer Croc even though he’s never killed anybody. He’s really just a common thief but the way he looks got him some unwanted attention and expectations.

Waylon is pretty sure this is all temporary and that one day he’ll be back to normal, even when the tail came and the bone structure of his face changed to accommodate all the teeth, and even when his feet and hands changed to be more crocodilian. He is sure that any day now he’ll have enough money and find the right doctor to get it all fixed and he’ll have that white picket fence dream. That dream will just have to include live or freshly killed raw animals since that’s all he can eat now.

He and Babydoll/Mary met when they were both at a low point and trying to find work. Babydoll was already a self identified rogue though. That work happened to be porn. They met while waiting to audition and Mary didn’t end up going through with it, but Waylon did. They hit it off with eachother though.

Mary didn’t want to add to the creepy attention she already gets sometimes. Waylon however likes being on camera and since the director at the time was looking for weird Waylon knew his skin and odd features was likely to get him the job this time instead of keep him from getting hired. It started off as a last ditch effort thing but he has found that he enjoys it and it helps his self esteem about his “temporary” state of being.

He and Mary started dating and she didn’t have any hang ups about him doing porn as long as she gets to be his manager so to speak and makes sure he’s getting paid properly and that he’s always comfortable with what’s going on. She’s always on set when he’s working and despite people insisting it should, it doesn’t bother her or make her feel like “less of a Woman.” Thanks to Mary managing his career he doesn’t have to steal so much anymore but most of his friends are rogues so he still gets caught up in stuff and has been in Arkham a few times.

Waylon has gotten some unkind jokes thrown his way about dating Mary. To anyone who is around her for more than ten minutes or to anyone who isn’t just ignorant, Mary does not look or seem like a child, she looks like an adult with dwarfism. There’s visible signs of aging in her face and skin, she has adult teeth, and she doesn’t have any childlike mannerisms besides the toy shaped weapons and her rogue name but that’s more of a play on her being treated like a doll without feelings by the entertainment industry when she was acting. The way she dresses is emulating dolls too.

Still Waylon gets called a creep which Mary will shout at anyone for because she knows better than anyone what the real creeps are like regarding her appearance. She also doesn’t like the idea that because of her disability she can’t date anyone who doesn’t also have dwarfism. She appreciates Waylon bearing the brunt of such things for her.

Waylon lives in a part of the sewer with Clayface who is not a good roommate because he doesn’t clean anything, Waylon still lets him live there though. They technically live in an abandoned part of the train system but the only way in anymore is through the sewers. Bane was their roommate before getting put in Arkham. They use the platform as a common area and some old cars as bedrooms.

[covenawhite66]

When an African Alligator lashes from the water to hunt mammals falling into its lake, its infamous teeth latch onto a hindquarter, jaws clenching with 5,000 pounds of force. Yet it's the water itself that does the killing, with the deep-breathed reptile dragging its prey to the deep end to drown.

The success of the croc's ambush of prey llies in the nanoscopic scuba tanks—hemoglobins—that course through its bloodstream, unloading oxygen from lungs to tissues at a slow but steady clip that allows it to go hours without air.

Crocodilians—crocodiles, alligators and their kin—the role of organic phosphates was supplanted by a molecule, bicarbonate, that is produced from the breakdown of carbon dioxide.

Comparing the hemoglobin blueprints of the archosaur and crocodilian ancestors also helped identify changes in amino acids—essentially the joints of the hemoglobin skeleton—that may have proved important.

[emmyrosee]

Here’s a fun random head canon list for my boys because I can and will have fun HA

———

Axel is the pied piper of kids. No matter who or what the situation is, Axel is just unfathomably good with kids. There is never a crying child when he is near, and babies?? As soon as they lay their eyes on him, it is like all is good in their world. 

Maybe it’s because he’s like, a human jungle gym. Who knows 😍

Gordan is EXTREMELY flexible and (super secretly) a HUGE yoga buff. Like oh my god. He does yoga in the mornings to stretch out his bones and muscles, going especially hard on himself after a mission where he can be home and relax a few days.

One morning you came down to make him breakfast and you saw him in a complete backbend, breathing through his nose, the gaps in his ribs huge with the bend.

“You enjoying the show?” He hums calmly, smiling softly with his eyes still in a relaxed close. 

“Very much,” you tease, taking a seat on the couch. “Please, don’t let me stop you.” 🙈

Henry Pearl is one of the most brave bills when it comes to doing daring things. He’s always the first one to go night swimming with you, always the first in line to go on that rollercoaster, and always the first to capture and remove the massive spiders in your house.

He says it’s because he’s doing something he loves and he wants to live after being sheltered so long but.. you don’t miss the opportunity to call him crazy😂❤

Mark’s favorite guilty pleasure is McDonald’s, and he gets it typically when he has a long night of studying, a hungover friend or when he’s just had a really bad day; his favorite food in the world is a McRib and would kill one of his friends for an Oreo McFlurry most days 🙄❤

Mateo has extremely vivid dreams, so much so that he’s been late to classes, meetings, lunches/breakfasts with you because in his dream he’s gotten up and done all of those things, while in reality, he is still very much asleep. 

Whenever he has something important for work, you’re sure to call him on his house phone to wake him up and get him moving so he’s not late, though this isn’t always fool proof. Because sometimes in his dream he answers it and completely misses the call, so an alarm clock across the room is what typically works😩

Mickey is really bad at subtraction and division. Asking him about multiplication, easy, addition, no sweat, but as soon as you start asking him on the fly reducing, he has a full meltdown, trying to figure it out but ultimately just grumbles at you to use his phone 😂

Roman has a very, VERY secret fear of turtles, as well as an irrational fear of crocodiles/alligators. No matter how hard Roman has searched, the little minute differences between these crocs/gators trip him up, and he can’t tell the difference between snapping turtles and fun turtles. 

In turn, he tries his hardest to avoid all these creatures all together HA

(Subbing The Kid for) Henry Deaver can only eat Oreo’s- which are his favorite cookie- by first taking out the cream, soaking it in milk and eating it, followed by the cookies, one dry and one soaked. He also eats lucky charms by separating his marshmallows and cereal because “the cereal is my breakfast and the marshmallows are my dessert”

He so weird. Love him 😘

Willard is a whistler. When he walks, when he’s bored, when he’s doing basic, mundane tasks, he whistles to pass the time and keep focus, as well as keep his senses heightened. He whistles at you when you walk by, he even whistles when he’s mad in order to bring himself down a notch. Occasionally he even whistles when he breathes- and you make sure to tease him for it every time 😍

[ultimatetornshipper]

Maribat oct rarepairs - day 17

@maribat-october-rarepairs

Day 17 - Oct 17 - carving

Don’t ask Ondine how she ended up in the Gotham sewers hiding from a Joker attack. Don’t ask her how she stared at the carvings in the walls and immediately run. Don’t ask her how she forgot that American sewer, apparently, had fucking crocodiles. Or alligators or whatever they were called. But currently a pain of reptilian eyes were staring at her, peeking from the water. They were blood red and bore into her soul with a hauntingly human intelligence. She held its gaze as a deep guttural growl filled their surroundings.

She could smell his territorial anger and annoyance even through the stench of the sewer. She straightened her shoulders and stood her ground, mostly because she was sure she wouldn’t be able to outrun it, she had much more faith in her ability to fight. Afterall she was a meta with shark abilities. She could fight a crocodile. Sure it’d hurt like a bitch but she’d be fine.

The thing stood slowly until she was bending her neck back to meet its gaze. It smirked and-

Wait.

Her shoulders sagged with relief and she dropped her fighting stance.

“Oh,” she said, “You’re just a meta, like me,”

They look taken aback by her reaction and start growling again.

She lifted her hands in surrender, “Don’t worry, I don’t mean any harm, I’m just hiding here from a Joker attack. I’ll be out of your territory as soon as possible, I know how annoying it is for another to intrude on your territory. I’ll make it up to you. What do you like? Some fish maybe?”

During her little talk she’d leaned back onto the wall with the carvings, she could see them open and close their mouth in confusion. They looked her up and down, their brow furrowed.

She smiled at them, for once showing off her sharp teeth. Then, slowly, she stuck her hand out for a handshake, “I’m Ondine by the way, I use she/they pronouns,”

Their eyes lingered on her hand and she realized that one of the fingerless gloves she used to hide the fins between her fingers had fallen off during her escape.

She started to pull her hand back, suddenly conscious of the fact that no one had seen her without gloves in years. Before she could though, they grabbed it, yanking her forward and holding her hand in theirs. They studied her hand intently, pulling her fingers open and closed carefully. Then they rubbed their thumb over her skin. She watched as she saw them realize that it was too rough and hard to be that of a regular human. Ondine waited carefully for their reaction. Suddenly they looked up and their sharp red gaze met her own.

“You’re like me,” they said, whispering as though the moment would break if they spoke any louder.

She nodded slowly, smiling.

“My name is Killer croc,” they said, letting her go while sadness and resignation filled their voice. They looked at her expectantly. She shook her head, tilting her head.

“Not what they call you,” she said softly, smiling sadly, “That’s not who you are, that’s not their decision to make. I’m asking you your name... your real one,”

“Why do you care?” he huffed, but she didn’t miss the way a tear fell down his cheek during his attempted sneer. At this point he was sat down on the walkway of the sewer, staring at the floor.

She sat down next to them, their head far above her own. Ondine stared at her onw hands, one gloved, the other free.

She watched as a tear landed on the leather of her glove, a tear that could be no one’s but her own.

“Cause, like you said, I’m like you,” she whispered. They both sat there quietly, only the faint sounds of people screaming and fighting on the surface.

Just as she was convinced they weren’t going to tell her, they broke the silence.

“Waylon,” they said softly, and she turned to see tears streaming down their face, a broken smile on their face, “Waylon Jones,”

[sciencespies]

Modern Crocodiles Are Evolving at a Rapid Rate

https://sciencespies.com/nature/modern-crocodiles-are-evolving-at-a-rapid-rate/

Modern Crocodiles Are Evolving at a Rapid Rate

A gharial has the same skull shape as some extinct crocodiles. This skull shape has likely evolved three different times during the history of crocodiles. DeAgostini / Getty Images

Crocodiles look like they belong to another time, an era when reptiles ruled. But appearances can be deceiving. Today’s crocodiles are not holdovers that have gone unchanged since the Jurassic, but are one expression of a great, varied family that’s been around for over 235 million years. More than that, crocodiles are still evolving—and faster than they have at other times in their family’s scaly history.

The seemingly contradictory conclusion about crocodylian evolution comes from a recent study published in Proceedings of the Royal Society B by University College London anatomist Ryan Felice and colleagues. By comparing three-dimensional models to track anatomical landmarks on crocodylian skulls over time, the researchers found that modern crocodile species in Australia, southeast Asia and the Indo-Pacific are evolving quickly despite looking like semi-aquatic antiques. Modern croc species look so similar not because of conserving ancient traits, but because crocodiles are evolving the same skull shapes over and over again through time.

“Crocodylians just seem ancient and primordial and look a bit like Hollywood dinosaurs,” Felice says, not to mention that some species are among the largest reptiles on the planet. American alligators can grow to be 14 feet long, and saltwater crocodiles can get to be over 20 feet in length. On top of that, Felice notes, some fossil crocodiles superficially resemble living species. The spitting reptilian image can create a narrative that crocodiles haven’t changed much at all, content to lurk in the evolutionary backwaters. But that’s not the real story.

Today’s alligators, crocodiles and gharials—grouped together as crocodylians—shared a common ancestor back in the Cretaceous, around 95 million years ago. But crocodile history goes much deeper. Today’s alligators and crocodiles are just the remaining members of a broader, older group of reptiles called pseudosuchians—or crocodiles and their extinct relatives. The first pseudosuchians evolved over 235 million years ago, around the time that the first dinosaurs were making their mark on the Triassic landscape, and have gone through a vast array of changes through time.

Many fossil pseudosuchians were unlike any creatures alive today. Triassic animals called aetosaurs, for example, are sometimes called “armadillodiles” for the way these crocodile relatives resembled large, omnivorous armadillos. Around the same time there lived bipedal crocodile relatives like Poposaurus and Effigia, pseudosuchians that evolved dinosaur-like body plans and habits independently. In fact, during the Triassic there was a greater diversity of pseudosuchian species and body plans than dinosaurs. They, not the “terrible lizards,” were the dominant reptiles on land. That is, until massive volcanic eruptions triggered a mass extinction about 201 million years ago and many forms of pseudosuchians died out, allowing the dinosaurs to step out of the shadows.

But even in Jurassic and Cretaceous heyday of the dinosaurs, surviving lineages of pseudosuchians thrived. Some crocodile relatives spent their whole lives at sea. Sharp-toothed predators like Dakosaurus and Thalattosuchus hunted the oceans for prey alongside ichthyosaurs and plesiosaurs. Others were terrestrial carnivores that were stiff competition for dinosaurs. In prehistoric Brazil around 90 million years ago, land-dwelling crocodiles like Baurusuchus were among the apex predators of their time and bit into prey with blade-like teeth. And semi-aquatic ambush predators existed, too. Some of them were about the size of their modern counterparts, but a few were giants. Deinosuchus, the “terror crocodile,” was an alligator that could grow to be almost 40 feet long and lurked in North America’s swamps between 82 and 73 million years ago.

Even after the asteroid strike that ended the “Age of Dinosaurs,” some species of crocodile survived and continued to evolve in new ways. While mammals were going through a major evolutionary flowering, new terrestrial crocodiles—such as the “hoofed” crocodile Boverisuchus —evolved to chase after them. And even in recent times, until about 4,000 years ago, there lived terrestrial crocodiles in the South Pacific called mekosuchines that had teeth and jaws suited to crunching mollusks and insects. Crocodiles and their relatives haven’t been evolutionary slouches. Instead, these reptiles have rapidly responded to changing times.

To track how crocodile skull shapes changed through the ages, Felice and colleagues used a technique called geometric morphometrics to compare the skulls of 24 living crocodylian species and 19 of their fossil relatives. These three-dimensional models allowed researchers to look at different landmarks on the skulls—such as the placement of the eyes or the length of the snout— and track how anatomy has shifted over time and through evolutionary relationships.

A 19th century illustration shows the different skull shapes of three species of crocodylians.

The Print Collector / Getty Images

The analysis did more than track shape. Crocodile snout shapes are heavily-influenced by what those species eat. For example, very long, narrow snouts filled with many small teeth are considered clues to a diet heavy in fish. Living gharials have this shape, but so do some extinct marine crocodiles. Felice and colleagues hypothesize that this fish-eating snout shape has evolved at least three times in the history of crocodiles.

Two crocodiles with similar skull shapes, then, might not be close relatives. Instead, distantly-related crocodiles are converging on the same skull shapes because they’re feeding on similar prey and living in similar habitats, with an array of species repeating a small number of skull shapes. The fact that distantly-related branches on the crocodile family tree are converging on similar skull shapes, University of Tennessee paleontologist Stephanie Drumheller-Horton says, suggests that crocodiles are evolving rapidly to repeatedly fill the same set of niches.

And new studies are beginning to track just how quickly crocodiles are changing, especially modern species. Earlier this year Harvard University paleontologist Stephanie Pierce and colleagues reported that some modern crocodylian lineages are evolving rapidly. The study by Felice and coauthors adds to this picture. Crocodile species living through the landmasses of the southern Pacific—like the famous saltwater crocodile—are showing a high rate of evolutionary change over the past two million years. Over and over again, Felice and colleagues found, modern crocodiles are converging on a small set of skull shapes. Africa’s Nile crocodile and Morelet’s crocodile of Central America are not especially close relatives, for example, but they’ve evolved remarkably similar skull shapes. Likewise, today’s broad-snouted caiman of South America has a very similar skull to the extinct crocodile Voay whose remains are found in Madagascar. This is why they seem ancient. It’s not that they’ve gone unchanged, but that crocodiles are evolving into a limited number of forms over vast spans of time. Look at a saltwater crocodile and you’re seeing the revival of one of evolution’s greatest hits.

Recognizing the pattern is just a first step towards answering some deeper evolutionary questions. “With new and more sophisticated analytical techniques,” Pierce says, “we can start to better understand how and why they converged on similar morphologies.” The new study helps lay the groundwork for experts to investigate how particular diets influence the evolution of distinct skull shapes in both modern and fossil crocs. In addition, Pierce notes, a skull can come together during embryonic development in only so many ways. The number of anatomical forms crocodiles can take are influenced by what internal factors, such as growth, allow as well as outside influences like diet.

Digging in deeper to why crocodiles tend to repeat similar forms over time might help explain why today’s alligators, crocodiles and gharials seem so similar to each other. They are all semi-aquatic carnivores that hunt by ambush. There are no more terrestrial crocs, seagoing crocs, crocodiles with a varied toolkit of different-shaped teeth, or species like many of those that used to exist. Felice and colleagues estimate that of all the crocodile skull shapes that have existed, today’s species only represent about a third of that variety. But given the longstanding survival of these reptiles, could crocodiles someday undergo another evolutionary burst and evolve some of these lost forms again?

“It’s possible, but highly unlikely,” Felice says. There might be some characteristics inherent to modern crocodylians that prevent them from reclaiming some of their family’s past diversity. Living crocodylians generally have low, squat bodies with limbs that need to hold them up on land as well as push them through water. The need for an amphibious body makes them less efficient on land than mammalian carnivores and not quite as maneuverable as entirely-aquatic hunters, and so competition from other meat-eaters may keep them restricted. The global climate likely has a factor to play, as well. During warmer global climates, Drumheller-Horton says, crocodylian species spread and diversify. “But the crocodylians living today are the survivors of the last cycles of ice ages, so we’re looking at a fairly restricted sampling of the total diversity they once had,” she says. On top of that, many modern crocodylian species are facing habitat loss and other extinction threats created by humans. If the armored reptiles are to someday thrive again, they’ll need a major ecological shakeup to open a path to a new Age of Reptiles.

Animals

Evolution

Fossils

Paleontologists

Paleontology

Reptiles

wildlife

#Nature

[aelaer]

Animal au! (Can be shifter etc): Tony is a ferret (or tiger), Stephen would be a saltwater crocodile.

For those MCU fans also familiar with more obscure LOTR lore, this could be considered a birthday gift :P

Anyway, my serious fics haven't been writing themselves for the last three weeks or so, and this is the oldest fic prompt I have in my ask box. And uh, yeah, I don't think I can do a serious take on this. So silly/fun it is. No idea if the original prompter is still around (I think ask is from the summer), but here is my take on it!

(assume alternate first meeting in this fic)

Magical Mishap

Chars: Stephen, Tony (and FRIDAY)

Length: 1500 words

Rating: Gen

I'm going to kill you, Stephen Strange's furious voice blast through his head and wow, that was weird.

Tony opened his mouth automatically to retort, but all that came out was this weird chirp-like sound. He wrinkled his nose (and he could see it now, that was intriguing) and instead thought towards Stephen. I thought you had an oath of some sort, Doc. He'd only met the doctor-turned-wizard a few times, but the killing discussion had come early on (life of a superhero and all).

Funny enough, Stephen growled—as in, he was thinking at him and actually growled, deep and low and it was the most fucking terrifying thing he had ever heard—it's very hard to remember my oath when my mind's being slammed by the instincts of a goddamn alligator smelling the fresh meat of a rodent!

Crocodile, Tony thought back at him as he scurried up the table leg and well out of reach of Stephen's incredibly horrific line of teeth. And ferrets are part of the weasel family.

Stephen growled at him again and Tony's little ferret heart started thumping in instinctive terror. I told you not to touch anything! Anything! came from the sorcerer-turned-crocodile.

I didn't know that included the books! he shot back.

It included the books! The croc snapped his teeth, then he heard Stephen sigh in his head. I don't know when Wong or anyone will happen upon my study again, and frankly put, I'm not sure how long we can wait before animal instincts override proper thought and I decide just to eat you. We need to reverse this now.

Tony looked around from the table for a good shelf to jump to. I could just remain out of reach until someone comes around; that shelf's rather high. Could ferrets make that jump? He had no idea, but it was worth a shot. He was feeling rather jittery and it looked like a fun jump.

Not willing to take that risk, was Stephen's terse answer. Here, we can do this. Can you still read?

He looked around the desk until he found something in English. Seems so. His glasses connected to FRIDAY were on the ground with the rest of his clothes. At least they were still intact; Stephen's normal clothes were completely destroyed, and the Cloak was curled up by a hearth near the foyer and nowhere near this room. Maybe it could have helped.

He wondered what FRIDAY was seeing. Was FRIDAY alerting anyone? The only person Tony had any phone number info for in this weird group was Stephen at this time, and that had been a hard enough nut to crack. Still, after this he would make it a point to get Wong's number.

That shelf looked really interesting. He wanted to jump to it.

Tony Stark! rang loudly through his head and he blinked and peered at the reptile.

No need to shout, he grumbled.

I called you three times, was Stephen's answer. I need you to concentrate and try to remain in the human part of you. What is the page number in the book you just read?

The page numbers weren't in an alphabet he knew. He missed FRIDAY. Uh, it looks like a sideways six and eight.

Seventy-four, Stephen said. Okay. Now I need you to shove the book off the table.

It turned out that pushing a four-pound book when one weighed only three pounds was incredibly difficult. Still, he managed it, and the volume went to the floor with a heavy thump.

Stephen somehow managed to turn the book the right side up with his snout, but that's where his dexterity ended. I can't get to the right page. I need you to come down and turn it to the correct page.

His little ferret heart started pounding in fear again. Are you crazy? Tony snapped. You just said you were fighting against the want to eat me!

And that will only get worse the longer this continues! he retorted. Look, I'll back away as much as I can. Stephen, to his credit, did, but there was only so much room a ten-foot crocodile could back up in his study.

Tony sighed in his head. Yeah, okay. Fine. Don't move, or I'm going to the shelves to wait for Wong or another one of your wizard buddies.

Sorcerers. Another growl went through the room.

Don't do that, either! He scurried off the table and to the book. It turned out that ferret paws were nowhere near as useful for page turning as human hands, but they were a far cry better than what crocs had.

His animal instincts were going absolutely insane with the call of danger as he flipped through the pages as fast as he could. Tony stilled when Stephen shifted, but he didn't move his feet, so Tony remained on the floor flipping and flipping until he saw the sideways six and eight again.

He fled to the shelves and jumped and scrambled up until he was on top of the bookcase. Okay, I'm good! Tony called down.

Stephen sighed. You might regret your position. He walked back to the book.

I'm further from the crocodile and I absolutely don't regret it, Tony retorted. It was nice up here. Ooh, could he jump to the table from here? No, wait, that was against what he accomplished climbing up here in the first place. Stupid weasel brain.

I don't think I can say words aloud like this, Stephen mused to himself. I haven't done silent spellcasting of this sort, but I believe I can manage it.

There was then a heavy silence and in about fifteen seconds Tony began to feel the same weird shift he felt when he was turned into a ferret.

Then he realized just how infuriatingly right Stephen was when his three pound body turned into a 170 pound body and the bookcase was having absolutely none of it. It toppled over, spilling him and all of its books onto the carpet.

"Ow," Tony moaned.

"I did tell you so," said the very annoying wizard. 

Tony frowned in his direction, which only increased as he realized something. "Hey, how come you have clothes on already? I thought they were all ruined, Hulk-style." He started pushing the books aside to see if his clothes managed to avoid the bookcase, at least.

"Magic," was the very annoying answer, but Stephen did magic the bookcase back into its position so Tony didn't have to pull it up, at least. "Oh, found your glasses."

"Gimme," he gestured, and they were floated over. "You there, FRIDAY?" he asked.

"I'm here, boss."

"See the whole thing?"

"Yes, boss. I'm afraid I had no sort of protocol for dealing with this sort of situation. Should I have called one of the Avengers?"

Tony found his clothing after several more books were moved by he and Stephen. "Uh, no, no, you were right to wait to assess the situation for a few minutes." He shimmied on his boxers, then pants as Stephen politely pretended he didn't exist, public locker-room style, as he sent all his books back to the fallen shelves in whatever categorization he had going. "Next time, we're gonna have a phone number of another wizard—"

"Sorcerer."

"—sorcerer to call in case of magical mishap." He shot a look at Stephen. "Seriously, in case you do more work with us beyond this consulting you've agreed to, we'd want a number in case you're hurt, anyway."

Stephen sighed, but acquiesced with, "Fine. I'll see if Wong agrees to it."

Tony nodded and pulled his shirt over his head. "Oh, and FRI, delete all footage of the incident." No one needed to see him like that. Especially that ending.

"Yes boss."

Stephen frowned at him. "You're recording?"

"I record everything with these glasses."

The frown deepened. "Don't expect it to work in here for all future visits."

Tony now frowned. "I can stop it when you ask. There's no need to be an asshole about it."

"And you didn't need to be a douchebag who secretly records things," Stephen retorted lightly, still sorting his books.

"My glasses aren't very secretive. You've heard me talk at FRIDAY before." He sat down and pulled on his socks, then shoes. "I figured you knew."

"People don't normally record their whole life."

"Have you never been on YouTube or something?"

Stephen sighed. "You're really irritating."

"That makes two of us," Tony retorted, but he threw the wizard—sorcerer—a bone. "I'll cut the recording. There, done." He leaned back in the seat. "And I won't look inside any books anymore. Lesson learned."

Another sigh, but Stephen stacked the remaining books that needed sorting in a pile (with magic, of course) and took a seat at his desk, across from where Tony sat. "I'm tempted to never let you in here again, if this is how visits are going to be." But he was summoning some sort of drink, two cups, and actions spoke louder than words in Tony's world.

"I'll be better behaved next time," he replied, tone overly serious. "But moving on: like I told you, I found something that I think is more in your field than mine."

As he gave Stephen the small puzzle box with weird energy vibes, and saw the man's face light up in fascination and intense concentration, Tony figured that despite their differences (and similarities), that he could, in the end, potentially really get along with Stephen Strange.

[xtruss]

ANIMALS

Ten Most Powerful Animal Bites on the Planet

Fearsome apex predators with the strongest jaws in the World.

— Steven Hill/Field and Stream | August 23, 2019 | Popular Science

— This article was originally published on Field & Stream.

Wild animals bring many awe-inspiring physical traits to their battle for survival, including the ability to use their teeth and jaws for self-defense and feeding. Not surprisingly, nature’s strongest jaws often belong to apex predators who sit comfortably atop the food chain, and collecting hard data on the force of their bites can be a decidedly risky proposition. Researchers have used a number of methods, from direct measurement to computer software modeling, to estimate the forces at work in nature’s bite club. Expressed as PSI (pound-force per square inch, a pressure of one-pound of force applied to a surface area of one square inch), here’s how some of the strongest jaws in the wild stack up.

1. Saltwater Crocodile

Saltwater crocs have the highest bite force ever recorded. Cultura Creative/Alamy

Bite Force: 3,700 PSI

Dr. Gregory Erickson, professor of anatomy and paleobiology at Florida State University and curator of the school’s Biological Science Museum, conducted a 10-year study to scientifically measure jaw strength in all 23 crocodile species. Erickson and his team placed a specially designed bite force transducer—which he likens to “an expensive bathroom scale” wrapped in “protective layers of bullhide”—between the jaws of multiple crocodile specimens. The highest reading, 3,700 PSI, was registered by a 17-foot saltwater croc. “It’s the highest bite force ever recorded,” Erickson says, “beating a 2,980-PSI value for a 13-foot wild American alligator.”

Notably, the team’s data allows projections of bite-force strength in now-extinct crocodiles found in the fossil record, including 40-footers estimated to have been capable of generating 23,000 pounds of force. That surpasses estimates for Tyrannosaurus rex, which Erickson estimated, in a 2017 study, probably had a bite force around 8,000 PSI.

“If you can bench press a pickup truck, you can escape a croc’s jaws,” Erickson says. Otherwise, “It is a one-way street between the teeth and the stomach of a large croc.”

2. Great White Shark

A breaching great white attacks a seal. Sergey Uryadnikov/Alamy

Bite Force: 4,000 PSI

In 2008, a team of Australian scientists led by Steve Wroe used sophisticated computer modeling based on multiple x-ray images of shark skulls to estimate that a 21-foot great white shark can produce nearly 4,000 PSI of bite force. Because bite strength in sharks is highly dependent on size; the much more common 11- to 15-foot great whites would pack considerably less punch than a similarly sized croc. And Wroe’s projections, unlike Erickson’s findings, have not been directly measured in field tests. Volunteers, anyone?

3. Hippopotamus

Hippos are capable of biting crocodiles in half. David Fettes/Alamy

Bite Force: 1,800 PSI

With tusks that can grow two feet long, a mouth that opens 180 degrees, and a bite that can crush a whole watermelon like a grape, hippos likely have the strongest jaws of any herbivore on the planet. Territorial and potentially aggressive, hippos are particularly hostile to crocodiles and are said to be capable of biting a 10-foot croc in half. The bite force of females have been measured at 1,800 PSI; males have reportedly proven too aggressive to test.

4. Jaguar

A jaguar feeding on its prey. Alan Tunnicliffe/Alamy

Bite Force: 1,500 PSI

The largest cat in the Americas is also the strongest biter of any wild feline. Unlike all other cats, which mostly go for the throat to dispatch their prey, the jaguar kills by biting its victim’s skull and is capable of puncturing a turtle’s shell with its teeth.

5. Gorilla

Gorillas are mostly herbivores, but have a powerful bite force. Francisco de Casa/Alamy

Bite Force: 1,300 PSI

It not so much the teeth, but the massive neck and jaw muscles that give the gorilla one of the most powerful bites in the primate kingdom. They’re herbivores, yes, but their diet includes much tougher stuff than bananas: The gorilla’s strong molars allow them chew heavy shoots, bark, nuts, tubers and other fibrous foods. Long, sharp canines seen in mature males are mostly for display.

6. Polar Bear

A polar bear feeds on a seal in Norway. ImageBROKER/Alamy

Bite Force: 1,200 PSI

Unlike most bears, whose teeth are designed to handle both flora and fauna, polar bears are exclusively meat eaters—hypercarnivore is the term. As a result, their bite is well adapted to dealing with the kind of prey they encounter in the Arctic: thick-skinned, heavily-feathered or, occasionally, North Face-clad. Polar bears are said to be the only mammal that actively hunts humans.

7. Spotted Hyena

A spotted hyena with the remains of a buffalo. Carol J. Saunders/Alamy

Bite Force: 1,100 PSI

Hyenas are skilled hunters that often make their own kills, but their tremendous jaw strength also allows these African mammals to profitably scavenge carcasses other predators leave behind. Dual-purpose teeth allow them to shear flesh and crush bone, and large jaw muscles combined with a unique arched structure that protects the skull against the forces generated by their own bite makes hyenas particularly efficient scavengers: When a hyena pack descends on a kill, there are rarely any leftovers.

8. Bengal Tiger

Tigers have a measured bite force twice that of lions. Mauritius images/Alamy

Bite Force: 1,050 PSI

Boasting the longest canine teeth (2.5 to 3 inches) of all cats, Bengal tigers present a fearsome display; they also have the force to back it up, delivering more than a thousand pounds-per-square inch of pressure—almost twice as much bite force as the king of the jungle.

9. Grizzly Bear

A fall grizzly in the Yukon Territories. ImageBROKER/Alamy

Bite Force: 975 PSI

Mythologized for their purported ability to decapitate a moose with a single swipe of their massive paws, grizzlies also have one of the more fearsome set of choppers in the wild. Doctors in bear country have developed antibiotic cocktails to fight the deep-tissue bacterial infections that survivors of grizzly bites often face. Their bite force is said to be strong enough to crush a bowling ball.

10. Lion

Though formidable, lions possess a bite force not much greater than a dog. Rodger Shearer/Alamy

Bite Force: 650 PSI

Lions have a bite force of only 650 PSI, which is not much stronger than the hardest-biting domestic dog, the English mastiff (550 PSI). But lions are social creatures that hunt in groups and consume their kill where it falls, which may lessen the need for individual jaw strength, some researchers have hypothesized. By comparison, humans exert a bite force of around 160 PSI when we clamp down—good enough to power through a tough steak sandwich, but nowhere near adequate for bringing a wildebeest to bay.

[liveindiatimes]

New Post has been published on https://www.liveindiatimes.com/escape-from-reality-a-virtual-tour-of-orlando-florida-for-you-and-your-little-ones-travel/

Escape from reality: A virtual tour of Orlando, Florida for you and your little ones - travel

Whether you want to soar down a rollercoaster, or have some fun touring theme parks, a virtual tour of Orlando could be a good getaway for all the young travel-bunnies stuck at home.

“We recognise that now, more than ever, we all want to escape from reality, even if it’s just for a moment. Whether you like floating down a lazy river in one of our resort pools or immersing yourself into The Wizarding World of Harry Potter, we hope these experiences provide a much-needed break from everyday life,” said George Aguel, President and CEO of Visit Orlando.

From the comfort of your home, the ‘virtual visitors’ can now soar down a 200-feet roller coaster drop, watch fireworks over the famous Cinderella Castle, zipline over alligators and even learn from experts how to draw Mickey Mouse, on Visit Orlando’s blog.

Walt Disney World

Watch a sneak peek of new rides like ‘Mickey and Minnie’s Runaway Railway’ and ‘Star Wars: Rise of the Resistance’, enjoy character meet-and-greets and more on the Disney Parks YouTube channel.

Universal Orlando Resort

Travel to different worlds virtually like The Wizarding World of Harry Potter – Diagon Alley and experience the parks with 360-degree videos of some of the most popular roller coasters, explore holiday events and take a closer look into the restaurants that make up Universal CityWalk, on the Universal Orlando Resort’s YouTube channel.

Virtual Relaxation

Relax and virtually float through by yourself down the winding lazy river that is part of the 5-acre waterpark located in the luxurious grounds of the Four Seasons Resort Orlando at Walt Disney World Resort.

Explore a lake on a giant swan-shaped boat, through the swan boat ride in downtown Orlando’s Lake Eola Park.

Float down the river with gushing geysers at Aquatica’s Roa’s Rapids at the Aquatica Orlando water park, in a virtual action river experience with high tides and gushing geysers.

Animal Interactions

From Gatorland’s School of Croc, a Facebook live every day at 10 a.m. every showcases animals and adventures. In the afternoon, their YouTube channel shares live-action encounters with animals including Burmese pythons, crocodiles, alligators and monitor lizards. Peak into animal habitats through a new daily video series on Facebook live, from the Central Florida Zoo.

High-Speed Thrills

Virtually experience indoor skydiving at iFLY Orlando inside of their high-energy vertical wind tunnels that allows visitors to float on a column of air. Get in the driver’s seat for a virtual race through Andretti Indoor Karting and Games’ indoor track of turns and high-speed chases.

Virtual Learning

You can now stream educational IMAX films typically shown in the cinedome of the Orlando Science Center. Enjoy MacGillivray Freeman IMAX films by streaming, America’s Musical Journey on YouTube, and Dream Big, Humpback Whale and National Parks Adventure on Vimeo on Demand.

Learn about living in space, Mars and rocketry or tour Space Shuttle Atlantis during a new series of Facebook lives from Kennedy Space Center.

From Disney Imagineers, learn real-world case studies and even design a theme park experience through interactive activities and lessons in theme park design and engineering.

Learn to draw Mickey Mouse as Disney shares a complete series of how-to tutorials on how to draw the famous figure on the Disney Parks YouTube channel. Cast member Stephen Ketchum provides expert tips on how to draw Mickey over the years, from vintage 1920s Mickey to the more contemporary “pied-eyed” version.

Music, Movies and Museums

Listen to intimate musical performances at the Timucua Arts Foundation, set in the home grounds of the former music director for Cirque du Soleil. The foundation will post daily videos of previously recorded live performances on its Facebook page, also host a Digital Music Flea Market to help local musical artists.

Get a daily move recommendation and insider info on the film from a cinematic expert on the Enzian Theater’s Facebook page.

Explore the museum galleries of the Charles Hosmer Morse Museum of American Art via the museum’s website, with PDF versions of the object guides that are normally placed in each gallery. Learn the history behind the museum through two films available for streaming: ‘A Legacy for the Community’ and ‘The Tiffany Chapel: A Masterpiece Rediscovered’.

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[shirlleycoyle]

Crocodiles Evolved to Be Vegetarian ‘At Least Three Times’ in the Past

The idea of a vegetarian crocodile or alligator seems absurd, given how notorious these predators are for their sharp teeth, huge jaws, and deadly ambush skills.

But scientists studying tooth fossils from the age of dinosaurs have demonstrated that extinct crocodilians had a far wider range of diets than their modern relatives, and that some only ate plants, according to a study published on Thursday in Current Biology.

Keegan Melstrom and Randall Irmis, both researchers at the Natural History Museum of Utah, examined 146 teeth from 16 different extinct “crocodyliforms,” which refers to the family of reptiles that includes modern crocodiles, alligators, and gharials.

False color 3D images showing the range in shape of crocodyliform teeth. Image: Keegan Melstrom/NHMU

Using a technique that was initially developed to infer what extinct mammals ate, Melstrom and Irmis analyzed the dimensions and structures of the fossilized teeth and compared them to living crocodilians. In mammals, more complex dental structures suggest an omnivorous or herbivorous diet, while carnivores have relatively simple smiles adapted to tearing flesh.

The researchers found that crocodyliforms of the Mesozoic Period, better known as the age of the dinosaurs, evolved an enormous diversity of tooth shapes, and that some branches of the family tree contained omnivores and herbivores.

It’s not known what specific types of Mesozoic plants the vegetarian crocs ate, because their stomach contents were not preserved. It might be possible to learn more about their diet by searching for isotopes in the fossilized teeth, Melstrom said, but that comes at a high price to the specimens themselves.

“In the process of this analysis, parts of teeth are destroyed,” Melstrom told Motherboard in an email. “Currently we don’t have a great way of reconstructing the specific diet of these herbivores, but I am confident that future paleontologists will figure out a way!”

While previous studies had already produced evidence of herbivorous crocodilians, the new research showed that this adaptation popped up at least three times, and possibly as many as six, in the crocodile family’s past.

This image shows crocodyliform life reconstructions. Image: Jorge Gonzalez

These veggie crocs were wiped out by the extinction event that killed the dinosaurs, while a fraction of the carnivores pulled through and evolved into the impressive predators that lurk in waterways today.

Melstrom hopes to shed more light on the mystery of why some meat-lovers were able to survive, while the plant-eaters went extinct, as part of his dissertation research.

“One interesting thing that we see in some fantastic, detailed studies of mammals from through the mass extinction is that mammal herbivores also go extinct, despite being totally different groups living in different areas,” he said. “What this may mean is that animals that specialized in plants may have been more susceptible to extinction.”

Modern crocodiles are opportunistic eaters when it comes to meat, and will munch on insects, crabs, fish, mammals, and more.

“You name it they’ll eat it,” Melstrom said. “So, to me, that tells me this flexibility may have allowed them to survive.” He noted that these are “just hypotheses and need to be rigorously tested.”

Regardless of why they ultimately died out, plant-eating crocodiles show that the living members of a family tree can never capture the full diversity and scope of their ancient forebears.

Crocodiles Evolved to Be Vegetarian ‘At Least Three Times’ in the Past syndicated from https://triviaqaweb.wordpress.com/feed/

[kristablogs]

How do we know what dinosaurs looked like?

No one knows for sure what dinosaurs looked like, so artists make informed guesses based on these clues. (Thales Molina/)

You’ve seen enough museum models, illustrations, and CGI predators that you’d likely recognize a Tyrannosaurus rex if you saw one. But how can you be sure? Nobody has ever clapped eyes on one in real life, and even the best skeletons are often only 90 percent complete. Specialists called paleoartists do base their re-creations on hard evidence (bones, feathers, and bits of skin) but, just as often, well-informed guesses. We may never know exactly how T. rex and other prehistoric creatures like the Microraptor gui looked, but here’s how we landed on the current incarnations of these deceased beasts.

Stance

The way joints fit together informs a dino’s pose—along with a bit of inspiration from contemporary creatures. Without cartilage and other connective tissues, experts map extinct skeletons against how birds and reptiles stand and walk. Using those methods, they inferred that T. rex held its spine horizontally, which means the tail shot straight back rather than dragging as it was depicted prior to the ’70s.

Muscle and fat

Like reptiles, dinosaurs probably didn’t have much body fat, so they looked pretty swole. To determine just how stocky or svelte to render a species, paleontologists most often refer to the same muscle groups in birds. But sometimes there’s an evolutionary reason to make an area extra burly: A T. rex, for example, had to kill prey and bite through bone with only its jaw strength—hence its thick-neckedness.

Head

Tyrannosaurs’ smooth, toothy skulls are quite reptilian. But unlike crocs or gators, dinosaurs were terrestrial, so they may have needed to trap moisture inside their mouths to stay hydrated. That’s why many depictions have partial lips, more akin to lizards. Studying eye sockets tells artists how to orient the peepers. Frontward-angled holes, such as those on the Microraptor, would have pointed the eyeballs ahead.

Limbs

Bones’ structures can indicate how appendages moved. T. rex, for one, used to be shown with its hands facing down, like it was playing a piano, but a 2018 analysis of turkey and alligator shoulders determined their palms may have turned in. Similarly, the angle between M. gui’s shoulder blades and rib cage may have prevented its wings from lifting high enough to flap; wind-tunnel tests suggest these dinos glided.

Skin

Soft tissue generally doesn’t last underground, but sometimes we get lucky. For the T. rex, a small slice of fossilized skin found in Montana enabled artists to make a stamp of the texture and apply it to the rest of the body. Coloring is trickier: Designers take cues from the environment more than the fossil record. T. rex lived in semi-marshy areas and flood plains, so it likely had brownish-greenish dappled skin to blend in.

Feathers

Tiny cellular structures called melanosomes vary in color depending on their shape: Black ones are sausage-like; reds are round. Thanks to a very well-preserved M. gui feather, we know it shone raven. Nanostructures also suggest it had an iridescent sheen, like a crow or magpie. We’ve never dug up a plumed T. rex, but its close relatives often have protofeathers on their heads, backs, and tails, so we suspect the king did, too.

This story appears in the Spring 2020, Origins issue of Popular Science.