KNM WT 15000 is a member of the species Homo ergaster, a close
relative of modern humans. Looking at the skull in frontal view, note
the shape of the skull. It is more rounded than earlier species, it has
higher "vaulting" - it rises higher above the orbits, it does
not have a sagittal crest, nor the flaring zygomatics of more robust forms.
Yet the skull shows many characteristics of earlier species. Rotate the
skull to side view, and notice that there is still a good degree of prognathism
- the teeth and jaws project forward of the nasal opening. In modern humans
there is generally very little prognathism. Also not the presence of a
large supraorbital torus, or browridge, above the orbits.
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