Is the platypus one of the only mammals that lay eggs?

Answer 1

The platypus belongs to an exclusive group of mammals known as monotremes, or egg laying mammals. The only other animal in this group is the echidna. Although platypuses and echidnas lay eggs, they are still mammals because their young suckle on mothers' milk.

Answer 2

Platypuses are mammals because, like all mammals, they feed their young on mothers' milk. This is despite their being egg-laying mammals. The defining trait of a mammal is to have mammary glands, to produce milk for its young. The platypus produces its milk from numerous glands over its underside, unlike other mammals which have teats. Other reasons why platypuses are classified as mammals are that they have fur, are warm-blooded and breathe via lungs.

Reptiles do not feed their young on mothers' milk. They are cold blooded animals, and they have scaly skin, not fur like platypuses have.

Answer 3

Yes. There are two egg-laying mammals. The platypus and the echidna are both egg-laying mammals, or monotremes. They are still classified as mammals because they feed their young on mothers' milk - a characteristic unique to mammals alone.

There are just three known species of egg-laying mammals, or monotremes. They are the platypus and short-beaked echidna (Tachyglossus aculeatus) of Australia, and the long-beaked echidna (Zaglosssus bruijni) of Papua New Guinea. The echidna is sometimes called the spiny anteater, and there are several sub-species of the long-beaked echidna: the Western long-beaked echidna, Sir David's long-beaked echidna and the Eastern long-beaked echidna.