#paleo nerd

[itzbiologic]

⭐️ Edmontosaurus had hooves! ⭐️

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Edmontosaurus just made headlines after scientists discovered fossils showing it had hooves on all four feet. This making it the first animal in the fossil record to sport these structures millions of years before mammalian ungulates like horses, deer, alpaca, rhinos, tapirs, and many more.

This cow-shaped plant-eater roamed what is now Wyoming about 66 million years ago, and thanks to the exceptional preservation of two “dinosaur mummies,” researchers can now study its body in astonishing microscopic detail.

But what did paleontologists find?…

Two specimens (1 juvenile, 1 young adult) were uncovered by researchers from the University of Chicago. The dinosaurs’ soft tissues were remarkably well preserved after a rapid layer of clay enveloped their bodies, creating natural casts that captured them in lifelike detail at the moment of their sudden death. This clay-rich “mummy zone” of Wyoming is renowned for producing this form of exceptional preservation.

The fossils were analyzed using X-ray and CT scanning. Scan data revealed that: Edmontosaurus had flat, wedge-shaped hooves at the tips of its toes; Its front vs hind feet displayed different hoof forms; It was capable of both bipedal and quadrupedal locomotion; Added by me: Moving bipedally may have depended on the animal being young and lighter in built.

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🦕 A brief history (THAT WE KNOW OF) 🦖

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Edmontosaurus was a massive, plant-munching hadrosaur (the duck-billed kind) roaming out in North America alongside other dinosaurs like Triceratops and Tyrannosaurus towards the end of the Cretaceous period, 66 million years ago. It got to be over 40 feet long, grazed out in huge herds (dino cattle!), and was a go-to snack for T. rex, according to fossil bite mark patterns. The name is inspired by Edmonton, Alberta's capital, where the first fossils were discovered back in the early 1900s.

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👢Why Hooves Matter for Dinosaurs?

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You might wonder why it’s such a big deal that Edmontosaurus even had hooves. It’s because those feet reveal *how* the animal lived.

With a time gap of 10 million years, the Edmontosaurus's hooves performed nearly the same functions as those of our contemporary ungulate mammals like horses and cows: they provided traction on uneven terrain, supported its enormous weight, and absorbed shock.

It was thought that Edmontosaurus might have had hoof-like hind digits until this most recent fossil discovery. It is unquestionably groundbreaking to see them preserved in actual 3D detail rather than just trackways. Furthermore, these amazing "mummies" showed off a lot more about this dinosaur than just its hooves, including a raised hump from its cervical vertebrae to its thoracic vertebrae, "spikes" along its tail, thin skin covered in pebbly scales, and wrinkled hide around its ribs.

This is a fantastic illustration of convergent evolution for paleontologists (and us eager students). Dinosaurs had already developed a similar solution to the same biological problem—"how do I support this massive body?"—long before hoofed mammals existed. The lives and travels of these giants are better understood thanks to these kinds of discoveries, which also show how great designs evolve over time while maintaining a similar, relatable, and just amazing solution.

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Thank you for reading my post and viewing my paleo art! This world has a lot to offer us, and I can’t wait to see what happens next.

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Article on the find: https://www.science.org/doi/10.1126/science.adw3536

Science | AAAS

[hasellia]

Just Komik by Harashu (@Harashu96 on Twitter) (Via TroodonVet on Twitter)

[myfandomistingling]

Ellie: "I want to ask you something!"

Alan: "Is it about Dinosaurs?"

Ellie: "Do you wanna go on a date with me?"

Alan: "Can we talk about Dinosaurs on the date?"

[smylealong]

Dearc Sgiathanach

Some of you might have seen the news of “the largest pterosaur ever” or some variation of that doing rounds on various social media platforms. The statement is both true and false at the same time, and I will explain why.

Pterosaurs were the first vertebrate to have evolved powered flight. They appear abruptly in the fossil record in the Triassic period and from there on proceeded to evolve into a variety of shapes and sizes before dying out in the k-pg mass extinction which wiped out the dinosaurs as well. Like birds, pterosaurs, too, had very light bones and paper-thin bone walls, a feature that doesn’t lend well to fossilization. Therefore, finding a complete pterosaur fossil is extremely rare.

The newly identified species, Dearc sgiathanach (pronounced jark ski-an-ach), meaning “winged reptile” in Gaelic, belonged to the family ‘Ramphorhynchidae’ and lived during the Middle Jurassic approximately 170 million years ago. It is said to have achieved a wingspan around 2.5m to 3m (8.2 feet to 9.8 feet). That would make it a very large flying creature indeed, rivalling the wingspan of the Andean Condor which stands at 2.7m -3.04m (8.9 feet -10 feet). This specimen is also the most complete specimen found in Scotland, answering several questions in the pterosaur’s evolutionary history that arose from the paucity of fossils. This makes the discovery of Dearc sgiathanach a significant one globally.

However, this isn’t the biggest pterosaur ever. That credit goes to an animal from the Late Cretaceous (68-66 million years ago), called Quetzalcoatlus. Standing as tall as a giraffe, Quetzalcoatlus had a wingspan of about 10.9m (36 feet). To make a comparison for scale, Dearc sgiathanach was about as big as a King size mattress while Quetzalcoatlus was about as large as a two-seater airplane. There is a possibility that Hatzegopteryx, an Azhdarchid found in the Hatzeg island was about as big or bigger than Quetzalcoatlus, but there are not enough fossils of the animal to establish the fact.

In summation, what this means is that while Dearc sgiathanach was indeed a big pterosaur, it was by no means the biggest ever. However, it was the largest flying creature when it was alive, making it the biggest known JURASSIC pterosaur. It is also one of the most complete fossils of Pterosaurs ever found.

Illustration: Natalia Jagielska

Postcranial skeleton and dentition of Dearc sgiathanach. From Jagielska et al., 2022

[smylealong]

Some Pterosaurs

Quetzalcoatlus (The largest creature to have ever flown)

Tropeognathus

Pteranodon

Ramphorynchus

Arambourgiania

Nemicolopterus (smallest known pterosaur)

Kunpengopterus antipollicatus (Nicknamed Monkeydactyl because of its opposable thumbs).

Caelestiventus hanseni (Oldest known Pterosaur)

Hatzegopteryx

These wonderful creatures were the first vertebrates to have ever flown. They were not birds. They were not dinosaurs. They were reptiles who mastered the powered flight. They came in all shapes and sizes. From a giant with a wingspan rivaling that of a two-seater plane to a tiny arboreal creature with a wingspan of 10 inches, Pterosaurs were one of evolutions most bizarre and wonderful outcome. For the longest time, scientists had no idea how a creature, that resembled a broken umbrella, took to the skies. Even today, we can only hypothesize based on the tracks we have found. We can never know for certain for nothing like them exists today. What we do know about these marvelous creatures that the largest among them could cross continents in one flight that could last for days.

Pterosaurs were the true masters of the skies. I will shed more light on this wonderful lineage (if and) when I complete my essay on them.

[smylealong]

HAPPY NEW YEAR, MY DEAR MUTUALS!!

This has been a tumultuous year for a lot of us. It may feel like nothing is going our way. It has been a challenging year for me too, personally. But this little bubble of Tumblr has been my happy place. So here's me wishing you all a very happy and productive new year for you all. I hope 2022 goes better than the two years before it.

With love from the C-drama, K-drama and Paleo Nerd!

[smylealong]

One of the most memorable dinosaurs from Jurassic Park has to be the four-feet-tall, frill- waving, venom-spitting Dilophosaurus. But what if I told you, this dinosaur was neither four-feet-tall, nor did it have any frill, and almost certainly did not spit venom? Its bite may have been venomous, like that of a Komodo Dragon, but that remains a speculation at this point.

PC: Jurassic Park Franchise

But, before I speak about Dilophosaurus, let me take a moment to talk about another dinosaur called Megalosaurus.

Megalosaurus, meaning ‘big’/’tall’/’great’ lizard, is a large theropod carnivorous dinosaur that lived in the Middle Jurassic period (166 Mya). Megalosaurus was the first genus of non-avian dinosaur to have been named in 1824 by William Buckland. Megalosaurus was one of the three genera that Richard Owen used to coin the term Dinosauria.

When the first fossils of Dilophosaurs was discovered in Arizona between 1940-1942, the most complete specimen became the holotype of a new genus of Megalosaurus named Megalosaurus wetherilli by Samuel P. Welles. However, Welles found a larger skeleton belonging to the same species in 1964. Upon realizing that the creature had two crests on the skull, he renamed and reassigned the species the new genus Dilophosaurus, and the species, Dilophosaurus wetherilli. (The name is given to honor a Navajo councilor, John Wetherill.)

PC: Mark Stevenson

Dilophosaurus is one of the earliest large predatory dinosaurs, even though it is small compared to some of the later theropods. The largest known specimen weighed about 400 kilograms (880 lb), measured about 7 meters (23 ft) in length, and its skull was 590 millimeters (23+1⁄4 in) long. Dilophosaurus had a pair of high, thin and arched crests that went from near the nose to the mid-part of the skull near their antorbital fenestra. While the real purpose of the crests are not clear, scientists have suggested several reasons for them, including thermoregulation, attracting a mate, species recognition and sexual dimorphism, to name a few.

PC: Dilophosaurus wetherilli skull replica by EoFauna

The animal had a long neck that held the skull in a horizontal posture. Being a theropod, Dilophosaurus was a bipedal creature with shorter forelimbs. Based on the bones, paleontologists Phil Senter and Sullivan did an extensive study to conclude that Dilophosaurus was able to grip and hold objects between two hands, to grip and hold small objects in one hand, to seize objects close beneath the chest, to bring an object to the mouth, to perform a display by swinging the arms in an arc along the sides of the ribcage, to scratch the chest, belly, or the half of the other forelimb farthest from the body, to seize prey beneath the chest or the base of the neck, and to clutch objects to the chest. Dilophosaurus was unable to perform scratch-digging, hook-pulling, to hold objects between two fingertips of one hand, to maintain balance by extending the arms outwards to the sides, or to probe small crevices. (From Wikipedia).

[smylealong]

Weigeltisauridae

Flight is an evolutionary trait so rare that it has appeared only four times in the 3.5 billion years of history of life, viz. Insects, Pterosaurs, Birds, and Bats. Powered flight requires certain adaptations and each of the groups mentioned above evolved their own specialized techniques that enabled them to stay airborne for extended periods of time.

However, several animals have evolved gliding. Like with many other adaptations, the reptiles were the first to evolve the ability to glide. Weigeltisauridae were a family of gliding reptiles that lived during the Late Permian, between 258 to 252 million years ago, which makes it the oldest airborne vertebrate animal.

When the fossil was found in 1992, no one understood what the peculiar rods that stretched from the animal’s chest were. Because the skeleton was curved in on itself causing the bones to overlap, the specimen was especially challenging.

After spending weeks studying the fossil, Adam Pritchard and Hans-Dieter Sues have published a new detailed analysis of the specimen. According to them, the bony rods would support a winglike membrane that allowed the creature to glide. Scientists posit that the reptile was an arboreal creature that lived on a diet of insects.

In most gliding reptiles, the wing membrane are modified ribs. What makes Weigeltisauridae so unique is that the bones supporting the wing membrane protruded from the abdomen. The membrane itself was probably controlled by the abdominal muscles. They were probably closely related to the Drepanosaurus, a group of arboreal reptiles that lived during Late Triassic.