The spiny anteater is the common name for the echidna, a mammal indigenous to New Guinea and Australia. The spiny anteater is similar to its distant cousins, the anteaters of North America, in that its diet consists largely of insects. Unlike other anteaters, the spiny anteater is a monotreme, which are mammals that lay eggs.
The echidna derives its name from Greek mythology. Echidna was a mythological monster that was half-human and half-snake. She was a rival of Greek gods and was considered the progenitor of many mythological monsters.
The spiny anteater gets its name from the hundreds of spines that cover its body, causing it to look similar to a hedgehog or porcupine. One of its distinguishing features is its long, slim snout, and there is a species called the short-beaked echidna that has a smaller snout. The snout houses an elongated, sticky tongue, which it uses to snare insects such as ants and termites. The snout serves as both mouth and nose, and it is toothless.
Echidnas are squat, powerfully built diggers with compact limbs and formidable claws. An echidna will dig into ant and termite mounds and logs in order to find its prey. Like its cousin, the platypus, it is aided by its ability to use its snout to sense electronic pulses from its prey. This type of electroreception is also common in sharks and eels.
The spiny anteater and platypus are the only known monetremes. An echidna lays eggs that remain inside the mother’s pouch, similar to a marsupial’s, for about 10 days. After the egg hatches, the baby spiny anteater remains inside the mother’s pouch for six to eight weeks. When the young echidna is old enough to leave the pouch, the mother prepares a den for it to remain in while she forages. It will return to the den to nurse the baby every few days.
A female monotreme does produce milk, but it lactates through openings in its skin and not through nipples as other mammals do. It has a pair of patches on its skin where the lactating milk seeps and can be accessed by the young echidnas. It is weaned at about seven months old and begins foraging on its own.
Based on fossil records found in Australia, it is believed that other species of monotremes have existed but are now extinct. Evidence suggests that monotremes arose in Australia and moved across Antarctica into what is now South America. As of 2011, it is believed that no monotremes naturally reside outside of Australia or New Guinea.