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After 11 years of activity, our Paleoart folder is now full to capacity. I have closed this folder to submission attempts and have created a new folder for paleoart, Paleoart II, so please direct all artworks of prehistoric life to this folder and this folder only. Any paleoart submissions to the General Art folder will be declined without comment.

I have added a notice of this change to the rules on the main page, as well as to the description of the full folder (now renamed Paleoart I) to minimize possible misunderstandings.

Thank you to all of our members for continuing to make this group the biggest evolution-themed community on DeviantArt, 11 years and counting!
Hi loyal Domain of Darwin followers,

Over the past couple of weeks I have been shamefully neglectful of the group, and stupidly allowed a handful of submissions to expire. Unfortunately, it seems as though most of their notifications have disappeared from my inbox, so I cannot solicit them individually. Therefore, if you submitted something to the group in the past several weeks and it did not get accepted, please resubmit at your earliest convenience! Very sorry once again.
For centuries, dinosaurs have captured the public’s imagination through their massive proportions and power, and their ancestral connection to birds has more recently brought a new fascination to paleontology. But when a newly discovered dinosaur is both huge and covered in feathers, it becomes the stuff of legend—a true dragon shaped by evolution instead of mythos.

Meet Dakotaraptor steini, one of the largest “raptor” dinosaurs known to science. This 17-foot-long predator was described by Robert DePalma, curator of vertebrate paleontology at the Palm Beach Museum of Natural History, and colleagues in last month’s Paleontological Contributions. Hailing from the Hell Creek Formation’s 66-million-year-old boneyards, Dakotaraptor would have shared its sub-tropical, floodplain environment with Triceratops, Edmontosaurus, and Tyrannosaurus rex, so it was by no means the largest animal stomping around late Cretaceous North America. But among its fellow dromaeosaurs—the family of bipedal, carnivorous dinosaurs typified by an enlarged “killing claw” on each foot and a close affinity to birds—its only competitor was the much older Utahraptor, which predated the Hell Creek ecosystem by about 60 million years.

The Thing with Feathers

As yet, there is no direct fossil evidence that Utahraptor, Deinonychus, and a number of other dromaeosaurs were feathered, because many of them come from depositional sediment where the preservation of delicate feathers is not possible. We can infer that they were certainly feathered based on fossils of their German and Chinese cousins, who had the good fortune (to us, anyway) to fossilize in fine-grain limestone and volcanic ash. These have given us a breathtaking detail of feather preservation in dinosaurs like Archaeopteryx, from Germany’s Solnhofen quarries, and Microraptor, from the famous Liaoning formations of northern China.

These animals (and many like them) don’t merely have feathers, they have a specific sort of feather seen today in flying birds: long, vaned, barbed feathers with strong central quills. Since these feathers are directly known from both early ancestors and late descendants of these dinosaurs, it is reasonable to assume that the whole tribe possessed them—the trait is ancestral to the entire group. This method of inference is known as phylogenetic bracketing, and it is based on the same logic we use to determine that prehistoric mammals, known only from bones, were likely covered in hair.

Bracketing is a robust method of inference when we have a lot of data points, and for dromaeosaurs we do. But most of these data points come from smaller, more obviously birdlike members of the family, and there’s always been an undercurrent of doubt as to whether the larger members of the family would have them, too. What would a dinosaur so large, the skeptics ask, need long, quilled feathers for? Why does something far too big to fly need the sort of feather ostensibly used for flying? Dakotaraptor hasn’t answered all of these questions for us, but it has given us one of the most important data points yet.

Like its much smaller Mongolian cousin Velociraptor, Dakotaraptor has huge, obvious quill knobs on its arms. Knobs like these are clear signs of ligament attachment points for big, strong feathers with robust quills. But while the turkey-sized Velociraptor could have derived some aerodynamic advantage from its wings, Dakotaraptor was bigger than a grizzly bear. No one knows for sure what it was doing with wings, but one thing is certain—it wasn’t flying.

The Dakotaraptor, its Form and Function

Dakotaraptor might have been around the same size as its Utahraptor great-uncle, but its body plan was very different. Where Utah was stout, low-slung and muscular, Dakota was tall and lithe, something like a scaled-up Deinonychus. The proportions of its legs and feet would have enabled it to run faster than its stouter relatives. Like all dromaeosaurs, it possessed two enlarged claws—one on the second toe of each foot, and held off the ground—and these were massive and powerful, with larger muscle-attachment points than in related species. Its hands are tipped with huge claws and its arms long and flexible. Every element of its anatomy suggests an active, carnivorous lifestyle.

The large feathers on the arms of this giant dromaeosaur may offer further clues to its predatory behavior. Many different uses for arm-feathers in non-flying dinosaurs have been proposed, including the shielding of eggs during brooding, signaling for courtship, and aggressive territorial display. However, none of these functions require the amount of stress that large quill knobs imply. In living raptors—that is, hawks, falcons and eagles—prey is often struck with the feet, which show a curious similarity to those of dromaeosaurs. Birds of prey have massively enlarged talons on the second toe, as well as short ankles that provide the torque for squeezing the life out of their prey. The bird will hang on while standing atop its meal, wings outstretched for balance and protection as its weight bears down on those huge second-digit talons. So similar are the feet and legs of dromaeosaurs that paleontologist Denver Fowler has proposed a similar method for dispatching prey. This model, known as “raptor prey restraint”, is a likely explanation for the wings of Dakotaraptor: the sturdy quills would provide a balancing surface, and the strong arms a primitive flight stroke.

In its late Cretaceous ecosystem, Dakotaraptor’s size would have pitted it against a wide swath of competition from other predators. T. rex was considerably larger, with adults up to 40 feet in length, but tyrannosaurs are known to have complex growth stages and Dakotaraptor was almost certainly striving to dominate the same ecological niche as Tyrannosaurus juveniles. This would have set the giant raptor apart from Acheroraptor, the only other dromaeosaur known from the Hell Creek Formation. Acheroraptor was a coyote-sized little predator comparable to Velociraptor, and its much smaller prey would have made it largely ignorable to something the size of Dakotaraptor.

Dakotaraptor is known from several individuals that provided a collation of vertebrae, parts of the legs and feet, a complete arm and hand, and a number of scattered teeth. Some of the individuals these bones belonged to differed in size despite appearing fully mature, and this has led some researchers to speculate that Acheroraptor may actually be a smaller size morph of the same genus. Acheroraptor, however, is known only from a few pieces of the jaws, so the only overlap between material in the two dromaeosaurs is the teeth. While this makes direct comparison difficult, the teeth, at least, differ substantially: those belonging to Acheroraptor have strong and numerous serrations that the larger raptor lacks. Lead author DePalma is confident that the two are distinct, and has stated that “future fossil discoveries will no doubt reinforce the differences between the two taxa”.

That notwithstanding, there is much yet to be learned about this enormous dromaeosaur and its haunts and habits. As of yet we have no skull material and little from which to draw inference about social behavior, family structure or life history. The use of its feathers, while offering some tantalizing possibilities, is still much a mystery. But such is the joy of paleontology—each new discovery answers some questions and opens many more, ripe for exploration by those who dare.

This article was originally published at and has been republished here with permission.
If you have submitted something in the past 3 weeks and it's expired, please resubmit! I have been extremely busy and intended to set gallery submissions to 3 week expiries instead of 1 week, but stupidly forgot to set for all subfolders. Sorry for any inconvenience!
Jurassic World, the next entry in the Jurassic Park film series, is coming out in a little over a week. As the first Jurassic Park movie since 2001, it's been a major source of excitement among fans of the series. Based on that, along with the amount of hype it's been getting, it's likely to be one of this summer's major blockbusters.

On the other hand, among people who are interested in dinosaurs as science and not just entertainment, the reaction has been much more critical. This is mostly because the movie's dinosaurs still look about the same as they did in the original film in 1993. A lot of new data about dinosaurs has been collected over the past 22 years, and Jurassic World incorporates almost none of it. Thomas Holtz gave this summary: "The original movies brought the dinosaur research of the 1980s to 1990s viewers, and the latest one seems to bring the dinosaur research of the 1980s to the 2010s viewers."

Apart from fans of the series, there is one other group of people who seems especially pleased with this outcome, and that group is creationists. In this article, Answers in Genesis has commented that the movie made the right choice not putting feathers on any of its dinosaurs. They've previously released this DVD making the same point. Now that Jurassic World is about to come out, and the lack of feathers on any of its dinosaurs has been officially confirmed, AiG seems especially satisfied that no matter what evolutionary science has to say about how dinosaurs looked, ultimately it can't impact their largest and most popular depictions in our culture.

Unlike creationists who are praising the movie, the movie's director Colin Trevorrow is under no illusions that Jurassic World's dinosaurs are accurate, as he's stated here. This is why instead of jumping on the bandwagon to complain about his ignorance, I'd like to instead examine why he knowingly made his movie's dinosaurs look different from they probably looked in real life, and what that means for depictions of dinosaurs in movies of the future.

In the early 20th century, there were a few major movies where dinosaurs played a central role, the most famous being Gertie the Dinosaur (1914), The Lost World (1925), and King Kong (1933). Dinosaur movies continued to be made from the 1940s up to the 1980s, but by the middle of the 20th century attitudes about them had begun to change. Movies like The Valley of Gwangi (1969) sometimes acquired a cult following, but at this point dinosaurs were no longer considered blockbuster material. They were the stuff of monster movies with relatively small budgets, with their special effects done using animatronics or stop-motion, which never looked completely real no matter how skilled the animators were.

Set against this pattern, it was no easy task for the original Jurassic Park to make audiences take it seriously as a blockbuster. There was only one way to do it, and that was by demonstrating to audiences in as many ways as possible that this movie was unlike any other dinosaur movie of the past fifty years. This effort shows in the movie's special effects, which were far more realistic than those in any dinosaur movie released up to that point, and it also shows in the movie's science. The clearest way for Spielberg to show audiences that this was a new kind of dinosaur movie was by making it the first movie to incorporate the ideas of the Dinosaur Renaissance, showing dinosaurs as active, warm-blooded animals that did not drag their tails.

The situation now is a very different one. There is no need to prove to audiences that dinosaurs are blockbuster material, because the first three Jurassic Park films already proved that in the 1990s and early 2000s. The amount of time it's been since Jurassic Park III is just long enough for the new film to profit from nostalgia, and Jurassic World's most important ambition is to appeal to people who saw the first three films as kids. In pursuit of that goal, making the dinosaurs look significantly different from how they did in the earlier films would be a risky move. And Colin Trevorrow is not interested in taking any risks with this movie--he's interested in replicating the earlier films as closely as possible, including how the dinosaurs look.

This is why complaints about the film's accuracy never had any real chance of changing Trevorrow's mind. Even if he had desired to make an up-to-date dinosaur film, I'm skeptical as to whether Universal Studios would have allowed it. Every company's main responsibility is to their stockholders, and stockholders always would rather see their money go towards a safe investment than towards a risky one. As long as copying the original Jurassic Park is the safest investment for major studios making dinosaur movies, that's what we'll continue to see.

Is there any chance for accurate dinosaur-themed blockbusters in the future? I think there is, but the first movie studio we see them from won't be one like Universal. Although major studios usually stick with whatever is financially the safest bet, there is a small class of directors and studios who occasionally try something a little more unorthodox. Think of Brad Bird and Pixar, who took a chance making a PG-rated movie (The Incredibles) despite the success of all Pixar's earlier films that had been rated G. Or think of Henry Selick and Laika, who took a huge number or risks with the stop-motion feature Coraline, which went on to be a critical and commercial success. Perhaps one day, an up-and-coming filmmaker will decide to take a similar risk with their depiction of dinosaurs. And if the movie becomes as successful as The Incredibles and Coraline have been, it may shape movie depictions of dinosaurs from that point forwards.

For now, we have Pixar's upcoming movie The Good Dinosaur to pin our hopes on. Based on what it's possible to see in the trailer, I'm not all that optimistic about the accuracy of its portrayal. But with Pixar, you can never know for sure.

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