Researchers working in South Dakota's Hell Creek Formation recently found a new species of raptor that is one of the largest on record, measuring a whopping 16 feet long. Further, this raptor had clear "quill knobs" in its forearms, indicating that the fearsome predator was at least partially feathered-- specifically, that it had stiff feathers sticking out of its arms.

For a raptor of its size, it is extremely unlikely that Dakotaraptor was flying around; instead, the feathers likely kept it (or its eggs) warm or served a display function. Feathers did not evolve for flight, but likely instead evolved due to sexual selection for display purposes or for insulation (keeping warm); since these feathers were stiff, pennaceous feathers, they may well have served a display purpose. What might this giant raptor have looked like in the middle of a mating dance? Maybe something like this.

Dakotaraptor, which lived 66 million years ago, had graceful long bones that indicate that it was very agile (unlike some other large raptors, such as the stocky Utahraptor). It had the agility of small, fast raptors, combined with fearsome proportions and a claw even larger than that of Deinonychus, which translates literally to "terrible claw."

In the original research study, the authors describe the fearsome predatory nature of this newly discovered raptor: "Dakotaraptor had a fortuitous combination of characters that made it a formidable predator: large body size and incredibly robust raptorial pedal ungual II similar to Utahraptor, and potential for speed and agility comparable to the smaller dromaeosaurids."

Members of this raptor family (Dromaeosauridae) were very likely pack hunters. Evidence for this comes from multiple skeletons found fossilized together, and from exceptionally preserved footprints. One fossil site shows footprints "left by two dinosaurs moving together in the same direction" including a trackway that "shows how one dinosaur abruptly changed speed to avoid running into its companion." While it is hard to infer behaviour from fossil evidence, these footprints clearly show that raptors were, at the very least, somewhat social. Yep- that means that everyone's favorite scene from Jurassic World was at least not totally impossible.