The Short-Beaked Echidna is the only native Echidna to Australia - the other 3 extant echidnas are native to Niu Gini! Thank you for the etymology! I had no idea they painted Ekhidna as such a gross sea-beast ๐
I studied the skeletal structure of T. aculeatus! They have a pectoral girdle that is really similar to the therapsids (mammal-like reptiles from the Permian/Triassic)! Shows how old of a species monotremes are! Their humerus is lateral to the body, giving them that waddle, and their tibia and fibula are "backwards" compared to mammals causing their hind feet to point caudally!
The maxilla and mandible of T. aculeatus is fused into a beak-like mouth. It isn't actually a beak, however, as it is made of specialised jaw bones and muscle, rather keratin coated bone (like a bird beak). They use their long tongue and long mouth to snuffle in soil for ants and termites (they are insectivores), and then use their tongue to grind up their food against a bony hard plate on the maxilla, along with a slight back and forth motion of their jaws, as opposed to the up and down motion humans do when we chew.