They are made of keratin, the same material from which human fingernails and tetrapod claws are made, and are structurally and compositionally very different from the scales of reptiles.
The pangolin scales are made of keratin.
The pangolin scales are made of keratin.
为该句子写一个更简单的版本: They are made of keratin, the same material from which human fingernails and tetrapod claws are made, and are structurally and compositionally very different from the scales of reptiles. 输出: