T. Rex Linked to Chickens, Ostriches

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T. Rex Linked to Chickens, Ostriches https://www.smithsonianmag.com/science-nature/t-rex-linked-to-chickens-ostriches-180940877/

The closest living relatives of Tyrannosaurus rex are birds such as chickens and ostriches, according to research published today in Science (and promptly reported in the New York Times). Paleontologists used material discovered in a chance find in 2003 to pin down the link.

The dinosaur-ness of birds has been suspected for many years based on anatomical similarities, but the new research is the first molecular evidence. For decades, dinosaurs were thought to be reptiles: big ones, to be sure, but basically cold-blooded, slow-moving, and dim-witted. The movie Jurassic Park popularized the idea of dinosaurs as quick, smart and birdlike. (The movie's ideas had been proposed in the 1970s--a book by paleontologist Robert Bakker, called The Dinosaur Heresies, nicely conveys this change in thinking and the controversy that accompanied it.)

To get molecular evidence about dinosaurs, you need some actual molecules--a tall order for a group of animals that died out 65 million years ago. But in 2003, scientists Jack Horner and Mary Schweitzer discovered some unfossilized material inside a T. rex bone by a combination of luck, desperation, and sharp eyes (see Smithsonian, May 2006). Faced with flying a giant femur out of a remote Montana field site, they broke the bone in half so it would fit inside their helicopter. If they'd had a larger helicopter, we might never have known.

Unlike in Jurassic Park, the real-life researchers couldn't recover any DNA from the ancient remains. But they did retrieve molecules of collagen, a structural protein that appears in slightly different forms in many animals. They compared the dinosaur version with 21 living animals, including humans, chimps, mice, chickens, ostriches, alligators and salmon. T. rex's collagen proved to be most similar to chickens and ostriches; its next closest match was to alligators.

Chickens and ostriches are only distantly related to each other, so the research says little about what kind of birds might be the closest relatives of the famous carnivore. The scientists noted that answering that question would require data from more molecules than just collagen. Whether they are currently cracking into any more giant fossils in search of material was not divulged.

Are Chickens Really The Closest Descendants Of T-Rex? https://earthbuddies.net/are-chickens-really-the-closest-descendants-of-t-rex/#:~:text=Y ou%20may%20have%20heard%20about,are%20closely%20related%20to%20dinosaur s.&text=A%2068%20million%20years%20old,chickens%20are%20the%20closest%20o ne.

Do you like chickens? Chickens have been consumed by human since ancient times. Even the breeding itself has been done since millions of years ago. You may see it as a mere food nowadays, but after you read this article, you may have more respect to the crispy wings on your table. Like other animals that walks on our earth nowadays, chickens are result of long evolution process of its ancestor. You may have heard about this, but indeed chickens are closely related to dinosaurs. Among other kind of birds, chickens, including turkeys, are the closest one. Although nowadays you see chickens are only eating seeds, their ancestor is one of the most feared predator at its time. A 68 million years old Tyrannosaurus Rex DNA was compared to DNA of 21 modern species of animals and from the analysis researchers found out that chickens are the closest one. The analysis of DNA was done to the fossil of dinosaur also known as T-Rex which was found in 2003. The fossil itself was unique, because it contained a little bit of soft tissues like blood vessel, which allow the researchers to extract sufficient amount of DNA for the research. The scientists were also comparing the DNA of a Mastodon fossil to modern days animals and the result was amazing. They found that the proteins found in the T-Rex fossil were most similar to those of chickens, and the mastodon were most similar to modern day elephants. For a long time, actually scientists have predicted the correlation between birds and dinosaurs based on the shape of their bones. But that was all just a prediction without any further researches. And the research conducted in 2008 gave the real answer. “We determined that T rex, in fact, grouped with birds – ostrich and chicken – better than any other organism that we studied,” said Prof John Asara from Harvard to Telegraph. It determined avians’ relationships with non-avian dinosaur’s evolution. “We also show that it groups better with birds than modern reptiles, such as alligators and green anole lizards,” he continued. It means that although dinosaurs were reptiles, modern days reptiles are their more distant cousins rather than birds. Following the research that found out the unpredictable close relationship between chickens and dinosaurs, another research was conducted. Bhart-Anjan Bhullar, who was a student in Arhat Abzhanov’s lab at Harvard, try to reverse back a chicken to its ancestor. Bhullar took sample from embryonic chickens and altered some of their genes. The result was amazing that by changing a few genes from the embryo, the test objects developed unusual similarities to dinosaurs. “Those chickens that were altered in that way, they grew up to have a snout that looked like a dinosaur snout,” said Bhullar as quoted from Inverse. Imagine if the research conducted further modification to more genes of the embryo, it may hatch as a dinosaur from the start.

2 However, Bhullar didn’t intend to reverse engineer the evolution and create a dinosaur like in the movie Jurassic Park. But he predicted that such thing may happen in the future. ““This isn’t theoretical. I’m not talking half a century here, I’m talking decades. It’s going to happen.” Bhullar, which is now a professor in Yale, still do some research about the relationship about avian animals and dinosaurs. The most concern is the beak of those birds, which was developed from usual dinosaur snout. He said that it may predict what kind of animal to roam on our earth in the future. Yes, we all know that dinosaurs met the extinction when a giant asteroid hit the earth, but actually not all of those dinosaurs died out. But actually, some dinosaurs with smaller size didn’t die out and survived the Armageddon. Those dinosaurs are the ones who evolved to nowadays birds. The smaller size of their bodies required less food than those with bigger size. And it was also easier for them to find shelter from following disasters after the asteroid hit the earth. Maybe that was why they could survive and finally maintain their kinds until evolving to nowadays modern avian. As a prove, you can trace chicken’s genetic ancestry to find out the look of the ancestor of this animal. And if you can do it far enough, you will find that its look resembles the shape of the fossils of dinosaurs you can find in the museum. And actually, it is pretty much easier to trace the ancestor of vertebrates than other kind of animals, because evolution often only hit us gently but for a very long time. “The secrets of the history of living things are locked away still in its inheritance, and specifically in the genome,” said Bhullar. Thus, in a vertebrate’s DNA, it is most likely to still contain genetic information of its ancestors. Although the information is not going to be 100% complete, but a lot of the information from the ancestors stored from a long time ago will still be in the species’ DNA. “There are only certain variations in anatomy that vertebrates produce, and it’s probably because we’re so intricate, we’re so complex, that majorly screwing something up early on is not going to easily produce a viable living thing,” Bhullar explained. Another prove of chickens’ close relationship with T-Rex is the finding of one feathery kind of dinosaur. About 85 million years ago, a dinosaur named Archaeopteryx roamed the earth. Archaeopteryx is a close relative to T-Rex and velociraptors. The dinosaur had all the birds’ features, they had wings and feathers all over their bodies. The shape of their bodies and the structure of their brains even resembled the modern days birds’ bodies and brains. The only difference is they didn’t have beak, instead they had toothy snouts. Based on the study that Bhullar conducts in his spare time, he stated that that only difference was just unevolved part of body. Bhullar found that actually modern days birds’ beaks are actually overgrown adaptation of a pair of tiny bones at the front of the birds’ face. Adaptation to environment and the way the animal looked for food was responsible for eliminating the toothy snout. The jaw bones shrank and the ‘beak bones’ grew longer to replace the jaw bones, giving the birds’ their current appearances.

3 Tyrannosaurus has never been found with feathers preserved, but its cousins tell us it wasn't the green scaly giant of our childhood. https://eartharchives.org/articles/did-t-rex-have-feathers/index.html

Since its discovery more than 100 years ago, Tyrannosaurus rex has reigned as king of the predatory dinosaurs. Popularized by countless books, television shows, and a certain 1993 movie, the "tyrant king" is well known to nearly everyone on Earth. It was a burly bear-faced monster with long banana-shaped teeth lining a mouth that could swallow a person whole. Tyrannosaurus stood on two strong legs, but had arms shorter than you or me. From snout to tail tip, its skin was covered in scales.

About that last bit though, are we sure it was scaly?

Tyrannosaurus and its closest kin, collectively known as tyrannosaurs, belong to a group of dinosaurs called coelurosaurs. They are known for their extremely birdlike anatomy and feathered fossils. These fossils show that dinosaurs' earliest feathers were hair-like. Over time, they evolved fluffy branched forms and eventually the flat-vaned feathers sported by birds we see today. The large tyrannosaurs from the latest Cretaceous, such as Tyrannosaurus, Tarbosaurus, Albertosaurus, and Gorgosaurus, left few skin impressions for us to study. These impressions were small, only about the size of a coin. From these impressions we can see that the feet and underside of the tail were covered in small scales.

Other impressions from other parts of the body are described as looking completely naked, or like plucked chicken skin. Unfortunately, none of these impressions have been formally published and illustrated in a scientific journal by researchers.

But is this information enough for paleontologists to claim that Tyrannosaurus was fluffy?

To determine the presence or absence of features not preserved in the fossil record, scientists use a method called phylogenetic bracketing. Phylogenetic bracketing looks

4 at the closest relatives of an organism and uses their anatomy to infer what was probably present but currently unknown. For instance, the extinct saber-toothed cat, Smilodon, is currently known from just bones and teeth. With phylogenetic bracketing, we can deduce that like other cats, it was covered in fur. What's more, phylogenetic bracketing predicts that its fur was probably tan colored with darker ring-shaped spots. Of course, finding a Smilodon fossil that certainly showed that it had naked skin or black fur would take priority over phylogenetic bracketing. But in the absence of such fossils, the most conservative approach is to trust the predictions of phylogenetic bracketing.

This technique can be applied to all sorts of extinct organisms, including, of course, Tyrannosaurus.

Tyrannosaurus may have not been found with feathers. But two earlier members of the tyrannosaur group — Dilong and Yutyrannus — were found with long, hair-like covering. Although we have discovered impressions showing scales on the feet and underside of the tail, the distribution of scales is similar to Juravenator, a coelurosaur known to have had both feathers and scales.

Additionally, the skin impressions from other parts of tyrannosaurs' body are described as naked or "plucked." This is consistent with animals that may have had feathers in life, but lost them before fossilization.

Based on our current knowledge, we can tell that Tyrannosaurus was quite unlike the pop culture image of a reptilian monster. While future fossil finds may answer this question with certainty, our current knowledge suggests that the king of the dinosaurs was fuzzier than we remember.