5. They lay eggs. Along with the platypus, the echidna is the only other living egg-laying mammal species. Almost a month after mating, the female deposits a single, soft-shelled, leathery egg into her pouch.

What are the 3 mammals that lay eggs?

These three groups are monotremes, marsupials, and the largest group, placental mammals. Monotremes are mammals that lay eggs. The only monotremes that are alive today are the spiny anteater, or echidna, and the platypus. They live in Australia, Tasmania, and New Guinea.

Do echidna have eggs?

Along with the platypus, the echidna is the only other living egg-laying mammal species. Almost a month after mating, the female deposits a single, soft-shelled, leathery egg into her pouch. The gestation period is quite quick – after only ten days the baby echidna hatches.