Echidna

Echidnas (/ɪˈkɪdnə/), sometimes known as spiny anteaters,[1] belong to the family Tachyglossidae in the monotreme order of egg-laying mammals. The four extant species, together with the platypus, are the only surviving members of the orderMonotremata, and are the only living mammals that lay eggs.[2] The diet of some species consists of ants and termites, but they are not closely related to the true anteaters of the Americas. Echidnas live in Australia and New Guinea.

Echidnas evolved between 20 and 50 million years ago, descending from a platypus-like monotreme.[3] This ancestor was aquatic, but echidnas adapted to life on land.[3]