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Velociraptors have been misunderstood ever since they were featured in Jurassic Park as giant scaly dinosaurs that hunted in packs and disemboweled prey with sickle-shaped claws. That portrayal got several things wrong. Velociraptors were actually feathered animals. They grew up to 100 pounds, about the size of a wolf. And they likely hunted solo—using their claws to clutch rather than slash prey—when they roamed central and eastern Asia between about 74 million and 70 million years ago, during the late Cretaceous period.

In fact, the raptors that terrorized Jurassic Park were based on a Velociraptor relative: Deinonychus antirrhopus,a much larger dinosaur that inhabited North America in the early Cretaceous period, about 145 to 100 million years ago.

So what were Velociraptors really like? Although our knowledge is still growing as more fossil evidence is unearthed, paleontologists have managed to learn a lot about these iconic predators.

Bird-like traits

There’s strong consensus among scientists that today’s birds are actually dinosaurs, and that they evolved from theropods, a family of three-toed predators that included Velociraptor mongoliensis and Tyrannosaurus rex. This family connection explains why Velociraptors had many traits found in modern-day birds, including their hinged ankles, swivel-jointed wrists, wishbones, and forward-facing toes. Most notable, though, was their plumage.

Researchers have long suspected that Velociraptors were feathered rather than covered with reptilian scales. In 2007, a study published in the journal Science found that a Velociraptor mongoliensis fossil had quill knobs—bumps along its forearm that anchor feather quills to the bone and are common in modern birds.

Unlike many of its avian relatives, however, this dinosaur was Earth-bound. Not only were its arms too short for flying, but Velociraptor’s wishbone—a forked bone between the neck and breast that generally serves as a spring to help birds fly—wasn’t the right shape to support flapping wings. Instead, the 2007 study hypothesized that Velociraptor’s feathers might have been an evolutionary leftover from smaller ancestors that could fly, or they might have served to attract mates, shield nests from the cold, or maneuver while running.

Still, Velociraptors are often likened to birds of prey such as eagles and hawks because of the long claw protruding from the second toe of each foot. Although scientists once theorized the claws may have been used for slashing, most now believe that the dinosaur used them to pierce and pin down prey as hawks do.

Hunting

Given a Latin name that means “quick plunderer,” Velociraptors clearly were thought to have been effective hunters. The bipeds had an excellent sense of smell, evidenced by the size and shape of the part of their skulls that held olfactory bulbs, the part of the brain that processes scent. Their muscular legs and long shins allowed them to take long strides and reach speeds estimated to hit 24 miles an hour. By moving with their clawed toes lifted, Velociraptors kept their talons sharp enough to pierce prey; once it was in their grasp, they likely finished the job with a jaw full of serrated teeth.

In Jurassic Park, Velociraptors were depicted as pack hunters. But there’s little evidence that this was the case—in fact, quite the contrary. A 2007 study conducted chemical tests of Velociraptor relative Deinonychus’ teeth to find out whether the dinosaur’s young ate the same foods as adults. These tests revealed that the dinosaur’s diet changed as it aged—a dietary diversity that isn’t generally seen among pack animals.

Given the chance, this predator likely wouldn’t have hunted humans, either. Despite the famous fossilization of a battle to the death between a Velociraptor and a much-larger Protoceratops, paleontologists believe that Velociraptors mainly preyed on small mammals and reptiles. In 2011, scientists also theorized that these predators were nocturnal, as their scleral ring—a bony disc that reinforces the eye—was wide and would have let in enough light to see at night.

Velociraptor also probably wasn’t as intelligent as popular culture has made it out to be. It’s true that this dinosaur had a large brain in proportion to its body, making it one of the more intelligent dinosaurs. But that’s a level of brainpower likely on par with average birds rather than the likes of chimps or parrots.

Velociraptor evolution

Scientists are still piecing together which ancestor species led to Velociraptor, as well as whether multiple types of Velociraptors existed. Velociraptor mongoliensis was first discovered in the Mongolian desert in 1924. In 2008, however, similar jaw bone fossils found in the same region puzzled paleontologists. These new fossils shared the same skull openings as Velociraptor, as well as a similar number of teeth. But their overall structure was distinct enough for scientists to describe a new species, Velociraptor osmolskae. Research into the life of this new and mysterious Velociraptor species is ongoing.

More recently, scientists discovered Velociraptor’s oldest known relative: a three-foot-long fluffy dinosaur named Hesperornithoides miessleri. Covered in feathers and sporting a sickle-shaped claw on each foot, this little hunter lived in the late Jurassic period, about 164 million to 145 million years ago. Though Hesperornithoides miessleri was apparently unable to fly, its existence suggests that dinosaurs began to evolve feathers and wing-like arms millions of years before the first birds appeared.

Velociraptor disappeared from the fossil record about 70 million years ago. A few million years later, a cataclysmic asteroid strike sparked an extinction event that wiped out the non-avian dinosaurs.

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