Skulls of Australopithecus sp and a Bonobo skull (for comparison). reference photos from Google. 

(edit 2/27: I added the rest of the set here:  Hominid skull picture set

Skulls of Australopithecus sp and a Bonobo skull (for comparison). reference photos from Google. 

(edit 2/27: I added the rest of the set here: Hominid skull picture set