marine reptile

ELASMOSAURUS
“Thin plate lizard”
Late Cretaceous, 80.5 million years ago

Elasmosaurus was a plesiosaur that could grow up to 46 feet in length – half of that length being neck! When first discovered in 1868, the prominent paleontologist Edward Drinker Cope mistook its attenuated neck for a tail, placing its head on its rear end. Cope’s professional rival, Othniel Charles Marsh, ridiculed him for this error, marking the scientific community’s first usage of “butthead” in peer review.

zeroodd asked:

Abby! As someone who is pretty smart on dinosaur stuff-Do you know what the link between creatures like the Monosaur and Plesiosaur to ocean animals now? Or are they also more related to birds and reptiles then sharks and such?

Ah! Good question– I’m gonna give you a long and kind of complicated answer, and since I am but a Junior Scientist, some of it may not be fully accurate, so get your grains of salt ready.

Marine reptiles, which refers to any reptile that returns to the sea (meaning they start out as terrestrial and over the course of millions of years become ocean-dwelling), don’t really have any living descendents (though there are a couple modern reptiles that could be called “marine reptiles”, such as sea turtles and marine iguanas). Ichthyosaurs died out in the mid-Cretaceous, right before the dinosaurs, and Plesiosaurs and Mosasaurs died along with the dinosaurs. As for their closest living relatives, that’s a little tricky!

A lot of folks agree that Mosasaurs are somewhat closely related to modern snakes and lizards, which means they most likely shared a common ancestor. For context, modern snakes evolved around the late Cretaceous, which is also when Mosasaurs ruled the seas. Snakes probably didn’t evolve from Mosasaurs, though there is an argument to be made for that– snakes more likely evolved from a burrowing reptile on land. Snake evolution is really weird and hotly debated!

Ichthyosaurs and Plesiosaurs (a group which includes both the long-necked plesiosaurs and the badass short-necked pliosaurs) are a little harder to place– Ichthyosaurs evolved in the late Triassic and it’s not quite agreed upon whether they are kind of related to lepidosaurs (snakes, lizards, tuataras) or are more closely related to Plesiosaurs. Plesiosaurs are part of a group called Sauropterygia, which is within the clade “Archosauria” and includes a lot of extinct animals, and Ichthyosaurs could be in the sister group to that, which would make them more closely related to modern crocodiles than to modern snakes and lizards.

This is all pretty confusing, so here’s a phylogenetic tree to help you visualize this stuff! I put Ichthyosaurs nearer to lepidosaurs than to Plesiosaurs, which could be inaccurate. You can see where dinosaurs and humans and sharks fit in to this, too– sharks, as you can see, are not closely related to any marine reptiles.

In case you haven’t encountered a lot of these, I’ll explain how a phylogenetic tree works! Each intersection, where the lines branch out (called a node), is where these organisms split off from a common ancestor. The length of the lines doesn’t have anything to do with passage of time or how closely related the organisms are, all that matters are the nodes! A sister group is two branches that come from the same node– so “mammals” are the sister group to “reptiles I guess”, and “pterosaurs” are the sister group to all dinosaurs. The group of branches coming from one node are collectively called a “clade”, and that clade can be given a name, like “archosauria” or “reptiles I guess”. Clades usually share some common features from their shared ancestor.

Hopefully this hasn’t just confused you even more! It’s a lot of information to take in, and it’s confusing information, at that. But here’s a summary: marine reptiles are like whales, but the reptile version– they started out as land-dwelling reptiles, then returned to the sea. Mosasaurs were more closely related to modern snakes and lizards, and Plesiosaurs may have shared a common ancestor with crocodiles (though they are very very different from crocodiles and probably looked a lot more like marine mammals!) Ichthyosaurs… could be either? Oh yeah, and they aren’t dinosaurs– they aren’t even very close to dinosaurs

PS: “Testudines” are modern turtles+tortoises– and they might be a part of archosauria, or they might not be! Until we nail down what the origin of turtles is, it’s really up in the air.

This large male Green sea turtle came into the reef for a much needed clean. I took a couple photos and then just sat with it for ten minutes as it got cleaned. It must have been at sea for a long time to be this dirty, or maybe it keeps getting creeped out by people staring at him every time he tries to get cleaned. It was such an old turtle, I cried I was so happy to share a moment with such an amazing creature. Currently listed as Endangered by the IUCN Red list. 

ATOPODENTATUS
“Absurd tooth”
Middle Triassic, 240 million years ago

This marine reptile bore a superficial resemblance to a sea lion or manatee (though it had four limbs, distinct from its tail). It had a flamingo-like beak lined with needle-like teeth, and a very unique, zipper-like cleft up the center of its top jaw, both of which lead scientists to believe it was a filter-feeder. It was given the name “absurd tooth,” presumably behind its back.

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California’s new state marine reptile

The endangered Pacific leatherback sea turtle, which makes an epic ocean-crossing journey each year to feast on sea nettle jellies off the California coast, is now the state’s official marine reptile. Gov. Jerry Brown signed the designation into law last week.

The Monterey Bay Aquarium was among the many ocean conservation organizations that supported the designation, introduced by Assemblymember Paul Fong of Mountain View. Fong was also the co-author of Aquarium-sponsored legislation that outlawed the shark fin trade in California.

Leatherback sea turtles are regular visitors to Monterey Bay. (That’s where staff member Alison Barratt took the photo above.) They make a 12,000-mile round trip journey from Indonesia to fatten up on jellies off our coast. Newly published research suggests that sea turtles may be able to sniff out the presence of ocean upwelling, which triggers the jellyfish blooms that turtles find so irresistible.

Unfortunately, longline fishing and development on leatherback nesting beaches have pushed this ancient reptile to the brink of extinction. We’re hoping its new status will bring attention to the threats facing leatherbacks and other sea turtles – and spark greater support for global conservation efforts.

That way, perhaps the leatherback will enjoy a better fate than the California grizzly bear, which survives only on the state flag. (Leatherback flag ©Oceana)

Starting in 2013, each October 15 is designated as Leatherback Conservation Day, with California schools encouraged to share the leatherback’s story with special activities for students.

MOSASAURUS
“Lizard of the Meuse River”
Late Cretaceous, 70-66 million years ago

Mosasaurus was a type of extinct marine reptile similar to a giant monitor lizard, but with fins. It would have been an apex predator of the Cretaceous seas, growing to almost 60 feet long!
The first Mosasaurus fossil was found in 1764 (about 50 years before the first dinosaur remains), though it wasn’t recognized as a marine reptile until around 1800 (roughly 40 years before the term “dinosaur” was coined). While it was instrumental in the understanding of extinction – and by extension modern biology as we know it – Mosasaurus was largely forgotten until its triumphant rediscovery in November 2014 as part of a movie trailer.

THE MARINE REPTILE TIMELINE

While the era of dinosaurs is now fairly fixed in the popular consciousness, far less attention is given to the reptiles of the same time period that returned to the sea. While not dinosaurs, these reptiles too reached impressive proportions- and gained traits, like live birth and warm-bloodedness, that we now associate with mammals.

Take my hand and I’ll walk you through the world of seafaring reptiles, all the way back to diminutive Mesosaurus 300 million years ago…

IT’S MARINE REPTILE TIME.

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DokiDot the Liopleurodon!
This adorable predator will be your huggable friend!
Baby soft minky fabric
Non clumping polyester cluster stuffing
Wool/Rayon felt teeth
and solid black safety eyes

$25+shipping
Payments accepted via paypal
contact me via ask or at GoldbloodedKiller@gmail.com if you’d like this plush or a similar one custom made for you.

Kinda sketchy drawing for ya!

The Triassic marine reptile, Atopodentatus unicus, is one of the most bizarre palaeontological finds of 2014, and that’s saying something. This unreal looking animal had an extremely unusual skull, and likely used it’s tightly-packed needle teeth to filter out small invertebrates from the water.

Here I’ve shown several views of Ato’. A full on side view, lateral view of the head and the anterior view of the head to show why this beasty would rather be drawn in profile. Gawd, someone needs to go to the dentist… 

(It’s good to be back after what seems like a long time. Hope you all enjoy!)