The more anthropomorphic primates
of the Hominini
tribe are placed in the Hominina
subtribe. They are characterized by the evolution of an increasingly erect bipedal
locomotion. The only extant
species is Homo sapiens
. Fossil records indicate this subtribe branched from the common ancestor with the chimpanzee
lineage about 3 to 5 million years ago.
Current evidence suggests that, about 2.6 million years ago, Australopithecus
began to diverge into two paths, on the one hand to Paranthropus
, more robust, specialized in an herbivorous
diet that required a stronger jaw and molars and powerful facial muscles that required a cranial crest, much like a modern gorilla
has, to unite them. The other track led to Homo
with a relatively larger brain, more delicate teeth and jaw. Both genera existed at the same time for about a million and a half years.
This subtribe is usually considered to include Australopithecus, Paranthropus, Sahelanthropus, Orrorin, Ardipithecus, Kenyanthropus, and Homo. However, the exact makeup is still under debate, as some scientists struggle to determine the order of descent in human evolution.
Key features of this group involve various adaptations for living terrestrially
instead of arboreally
. One feature is an erect bipedal stance and the skull placed on top of the vertebral column. The feet are not prehensile
unlike the rest of primates, since the first toe is built robustly and aligned with the other four. The hands have a developed opposable thumb and are quite adept at manipulating objects.