Question

ASAP! Please?

Answer 1

Answer: They aren't classified as birds because monotremes are mammals, unlike birds. They are referred to as mammals because they have mammary glands responsible for manufacturing and producing milk. Birds cannot do this.

Answer 2

Monotremes, like the Duck-billed Platypus, are not referred to as birds because they lactate, which is a function only possible with mammals, not avians.