How can some animals eat and digest an entire other animal (skin, fur and bones)?

Question

How can some animals eat and digest an entire other animal (skin, fur and bones)?

In: Biology

Answer 1

Many birds don’t digest everything: they spit up the fur, bones, shells, et cetera, a mass which is a called a [pellet](https://en.wikipedia.org/wiki/Pellet_(ornithology))