The Australopithecines have a brain size of about 500 cc, or similar to the brain size of chimpanzees. Homo habilis appeared about 2.2 million years ago and survived to about 1.6 million years ago. H. habilis is thought to have used crude stone tools, but it is unclear whether the species regularly hunted or mostly scavenged. H. habilis evolved and lived in sub-Saharan Africa. There is significant sexual dimorphism in Homo habilis .
Males are much larger than females.
Homo erectus Homo erectus appeared about 2 million years ago. This species overlaps H. habilis and may have eventually driven H. habilis to extinction. Homo erectus had a brain size of 800 to 1200 cc., which gradually increases until it merges with that of Homo sapiens . The upper limit overlaps that of Homo sapiens. Homo erectus definitely used tools and possibly fire, and migrated from Africa to Europe and Asia between 1,000,000 and 700,000 years ago.