Echidnas, also known as spiny anteaters, belong to the family
Tachyglossidae in the monotreme order of egg-laying mammals.
There are four extant species, which, together with the Platypus, are
the only surviving members of that order and are the only extant
mammals that lay eggs. Although their diet consists largely of ants
and termites, they are only distantly related to the true anteaters of
the Americas. They live in New Guinea and Australia. The echidnas are
named after a monster in ancient Greek mythology.