AI-powered
podcast player
Listen to all your favourite podcasts with AI-powered features
The Variety of Shells
A shell is a hard casing or covering in some sort and they can be made out of all kinds of things. There are plenty of calcium-based shells. Shells can be keratin in the case of like a, I think, an armadillo. Do my fingers have shells? I think they do. Is your skull a shell of a type?