Human Evolution: Australopithecus

Before getting started, a word on terminology: I will try to use genus names (Homo, Australopithecus, etc) or their abbreviations as much as possible, instead of saying ‘hominid’ or ‘hominin’, the reason being that those two words have traditionally been thrown around erroneously and without definition (is it only Homo? Is it all the Old World apes?). If I do happen to say hominin, I will mean those apes that diverged from the chimps already, not necessarily the genus Homo. Hominid I reserve to members of Homo.

Human Evolution: What Are Humans?

Before starting on anything, let’s go through an entire phylogenetic review of where humans are, listing the characteristics of each clade they belong to (note: not exhaustive lists, only what I can remember while typing – I have no vertebrate references to look at). Within the vertebrates, they belong to the Gnathostomata, the vertebrates with jaws and characterised by their skull. Within this clade, they are osteoganthostomes. In other words, they use bone, not cartilage, to build their skeleton.