A Creative World

As someone whose specialty is working on fossilized dinosaur skin, I have more than a passing interest in bird feet and the scales of reptiles.

Because the carnivorous theropod dinosaurs—a group of bipedal dinosaurs characterized by hollow bones and three-toed feet—eventually evolved into birds, the two groups share a lot of similarities.

So, we can use birds as a model for reconstructing the behavior and lifestyles of extinct dinosaurs.

Raptorial birds—think the likes of hawks and falcons—often have large, protruding toe pads that act like little fingers to help them grip their prey. Raptorial birds that specialize in catching fish also have spiky scales on the underside of the foot to assist in restraining their slippery catch.

For more than 25 years, extraordinary fossils of feathered dinosaurs have been emerging at a tremendous rate from Early Cretaceous (roughly 145 million to 100 million years ago) rocks in China.

They identified about a dozen fossils that preserved not only feathers, but, more importantly, the skin and scales surrounding the feet.

These fossils ranged from dromaeosaurs (the group of predatory dinosaurs that includes Velociraptor), such as Microraptor and Anchiornis, to more conventional-looking primitive birds, such as Sapeornis and Confuciusornis.