TED Ed: Claws vs Nails

Which finger structure appears first in the fossil record?

• Nails

• Claws

Which of these structures is not made of keratin?

• finger nails

• hair

• finger bones

• rhino horn

The aye-aye, a primate from Madagascar, is different from most other primates because

• It has a tail

• It has claws

• It can glide

• It does not have a thumb

Nails help primates to

• Be good swimmers

• Hear sound through the ground

• Dig efficiently

• Climb carefully

What is the main difference between a nail and a claw?

• Their size and shape

• What they are made of

• Their function (job)

• How much they grow

Fingernails, claws, and hooves are all made of keratin. What are some of the special properties of keratin? Which of these properties make keratin an especially useful material to have on an animal’s fingers and toes?