Brain is ⅔ the size of a human brain
Make sophisticated stone axes
First hominid with HUMAN VOICE and uses sound (not language)
Start to live together in troupes of monogamous couples for social relationships and not just survival
Some palaeontologists consider Homo Ergaster and Homo Erectus as separate species, some consider them as the same
The name means "Man who works"
Brain Size: 800-900 cm3
More advanced stone tools known as Aeschulian Technology
20% less sexual dimorphism than Australopithecus
Probably had more advanced language than Habilis
Most complete example was discovered in 1984 in Kenya by Kamoya Kimeu, contains 108 bones
Nicknamed "Turkana Boy" after Lake Turkana where it was found
Also known as "Nariokotome Boy"
5 feet tall and 150 pounds