See also: Tachyglossidae, Echidna
The Spiny Anteater, or Echidna, is a member of the monotreme order. Monotremes are mammals that lay eggs; the only other such kind of animal is the Platypus.
Spiny Anteaters are not particularily related to other animals called "Anteaters", nor to porcupines or hedgehogs!
There are two species of Spiny Anteater: the Short-Nosed Echidna (Tachyglossus aculeatus), and the Long-Nosed Echidna (Zaglossus bruijni). The Short-Nosed Echidna is found in Australia, Tasmania, and New Guinea, while the Long-Nosed Echidna is only found in New Guinea. Little is known about it, so this writeup is about the Short-Nosed Echidna only.
Spiny Anteaters do not at all look like platypi. They resemble porcupines or hedgehogs since they have sharp spines on their backs. These spines are usually yellow with black tips, but can be entirely yellow. Underneath the spines, Short-Nosed Echidnas are covered with dark brown or black body hair, although in one subspecies, the hair covers the spines almost completely. Their most prominent feature is the pointy snout and long, sticky tongue that they use to catch ants and termites. They weigh about 2 to 6 kg, and grow to a length of up to 53 cm. (Long-Nosed Echidnas can weigh up to 16 kg, and grow to lengths of 75 cm.)
Echidnas can survive basically everywhere there is a good supply of ants or termites. They can be found all over Australia, in deserts, forests and in the highlands.
They are solitary except for the mating season and are mainly nocturnal animals, particularily in dry regions. They do not display advanced social behaviour, like, for example, grooming, or the formation of lasting bonds between individuals.
They mainly feed at night, from ant and termite nests that they detect by locating the electrical signals of their prey with their sensitive snouts. When a nest is found, the Echidna will dig into it, exposing the ants or termites, and catching them with its tongue.
Being monotremes, these animals have a rather strange mode of reproduction: At the start of the mating season (July and August) the female will develop an egg pouch, similar to the pouch of a marsupial. Three weeks after mating, it digs a burrow where it lays a single, soft, leathery egg into its pouch. (Rarely, there are two or three eggs.) The egg hatches after ten days, and a small, blind and hairless Anteater emerges. It stays in the pouch for the next 8 to 12 weeks, suckling on a milk patch on its mother's skin. When the spines develop, it leaves the pouch but stays in the burrow for the next six months, with the mother coming back regularly to feed it. It becomes independent of the mother at the age of one year.
Spiny Anteaters get eaten by Goannas (lizards), Dingos and Foxes.
Unfortunately, they are also food for feral cats and dogs, which have wreaked havoc upon the fauna of Australia, Tasmania and New Guinea ever since they were introduced. Hundreds of Echidnas are also killed by cars every year. However, the Spiny Anteaters are currently not classified as a threatened species.
Information mainly taken from