Moreover, while human and canine nails grow continuously, cats shed the claw’s outer sheath, preventing the claws from getting too long. Q: I recently adopted Bentley, a 1-year-old toy poodle mix.

The sheath of keratin, similar to a human nail that covered its digits, was discovered by scientists from North Carolina State University. It is believed to have belonged to a Citipati dinosaur.

When cats claw, they are looking to remove the outer layers of their claws as new ones grow, making a stretch on a rough vertical surface enticing." A kitten tearing through a box.

The Duonychus tsogtbaatari fossils preserve the keratin sheath that covered its bony claw. Photograph by Kobayashi, et, al Dinosaur claws were made of bone covered in keratin sheaths, the same ...