__________ is the most primitive of the robust australopithecines and possibly the root ancestor.
A) Au. robustus
B) Au. aethiopicus
C) Au. boisei
D) Au. garhi

Question

Quizplus · Accepted Answer

Au. aethiopicus is considered the most primitive of the robust australopithecines and is believed to possibly be the root ancestor of this group.  This species lived about 2.5 million years ago in East Africa and had a distinctive bony ridge on its skull, indicating it had a powerful jaw for chewing tough foods. Au. robustus, Au. boisei, and Au. garhi are also robust australopithecines but are considered to have evolved after Au. aethiopicus.

__________ Is the Most Primitive of the Robust Australopithecines and Possibly