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Echidna, along with the platypus are fascinating animals. They are the remnants of ancient species and are a cross-over species exhibiting
characteristics of reptiles and mammals.
These animals are living proof that Darwin's evolutionary theory is correct.
Although echidnas lay eggs, they still produce milk from special patches of skin and are therefore classified as mammals.
The Australian population of echidnas consists of the short beaked variety (Tachyglossus aculeatus) although it is thought that
some members of the long beaked variety may still exist in the Kimberley region of Western Australia.
Three of the four known species of echidna inhabit New Guinea. These are the
Western long-beaked echidna (Z. bruijni)
Sir David's long-beaked echidna (Z. attenboroughi) and the
Eastern long-beaked echidna (Z. bartoni)
Echidnas evolved some 50 million years ago from a platypus like ancestor.
They exist on a diet of ants and termites which are drawn in by a long sticky tongue and ground against bony plates in the mouth. They have strong forelegs and large claws
that are ideal for breaking into termite mounds and tearing apart old logs to get at their food source.
The name echidna comes from an animal of Greek mythology that was said to be half snake, half human female. This was because the echidna shares attributes of
mammals and reptiles.
Usually black to brown in colour, there are sometimes albino specimens with white spines and pink eyes.
The echidna's active body temperature is only slightly higher than the platypus, which has the lowest of all mammal active temperatures.
The low metabolism of echidnas may account for their relatively long lifespan. It was thought they lived up to 16 years in the wild but it is now thought they may
live considerably longer than that. Captive echidna have lived as long as 50 years.
These creatures are unusual in a number of different ways, not least that the male has a 7 centimetre 4 headed penis and the female has a 2 branched reproductive tract.
The male must shut down two of the penile heads to copulate but then can alternate between the two sets during mating.
22 days after a successful mating the female lays one leathery egg directly into her pouch. Hatching takes place 10 days later and the puggle (the name for a baby echidna)
breaks out of the egg using a reptile like egg tooth.
After 45 to 55 days, the mother digs a burrow and leaves her puggle there for as much as 5 days while she is away feeding. The young can stay with their mother for
up to 12 months.
Breeding season lasts from June to September and lines of males will follow a female around with the lead male being the oldest and the last in line, the youngest.
Echidna hibernate and there are times when a male will enter a female's burrow while she is sleeping and mate with her.
The main natural threat to echidna is snakes. They enter the burrows and prey on young echidna. Introduced species such as foxes, cats and dogs are also a problem.
If threatened an adult echidna attempts to dig down to expose only its spines or can curl into a ball if caught in the open. Vehicles are also a large threat as the animals have no road sense at all.
Although echida are classified as long and short beaked, they have no real beak at all, it is a long fleshy nose. Like the platypus, male echidna have sharp spurs, but unlike the platypus, they are not venemous.
Kingdom: Animalia
Subkingdom: Bilateria
Infrakingdom: Deuterostomia
Phylum: Chordata
Subphylum: Vertebrata
Infraphylum: Gnathostomata
Superclass: Tetrapoda
Class: Mammalia
Subclass: Prototheria
Order: Monotremata
Family: Tachyglossidae
Genera: Zaglossus and Tachyglossus
Species:
Tachyglossus aculeatus (short-beaked echidna)
Zaglossus attenboroughi (Sir David's long-beaked echidna)
Zaglossus bartoni (Eastern long-beaked echidna)
Zaglossus bruijnii (Western long-beaked echidna, New Guinean echidna)
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