Pangolins are specialized to eat ants and termites. Waddling along on short legs, they use their keen sense of smell to locate insect nests. Digging into them with sharp claws, they create entry holes into which they can insert their tongues. A pangolin tongue is anchored way back inside its body near the hind limbs and is longer than the pangolin's body. As a pangolin rapidly flicks its tongue in and out gathering up insects, it consumes sand and small stones, too. A pangolin has no teeth, and its tongue carries the insects straight to its stomach. Its large muscles churn the insect bodies, grinding them against the sand and stones and breaking them down. Protruding stomach spines made of fingernail material (keratin) cause additional breakdown as food bangs against them. Even a pangolin's eyes are specialized for its diet; they are protected from insect bites by thick eyelids.

All mammals have hair, outgrowths of the skin, during at least some part of their development. While it evolved to insulate animals in cold climates, mammal hair has various functions. Long, stiff hairs (vibrissae, or whiskers) are found in all mammals but humans. Whether on the face, legs, or tail, vibrissae extend an animal's sense of touch. Some mammals, such as porcupines, have enlarged hairs that function as defensive spines. Defense is also achieved by raising individual hairs to make an animal look larger (such as an angry cat). Muscles in the skin make the hair stand up or lie down. Raising and lowering hair changes how much air is trapped under it, which also makes it more or less insulating. Mammals in cold climates tend to have an extra layer of insulating fur, or extra fat under their fur. Mammals in climates that change seasonally shed and replace their hair to create a thicker winter coat and a thinner summer coat.