Pangolins’ bodies are covered in overlapping scales made of keratin, the same as human fingernails. Scales provide defense against predators. They are sharp at the edges and strong enough to withstand bites. Scales grow continuously as old ones wear off. Arrangement allows curling into a protective ball. Scales also support digging and movement.
It’s a key defense adaptation in a slow-moving mammal.
Scales illustrate convergent evolution of armor in animals.
Pangolin scales can weigh up to one-fifth of total body weight.
Smithsonian National Zoo (si.edu)