Homo habilis: 2.2 to 1.6 million years ago ago; made tools

Homo erectus, left Africa 1 million years ago

Homo sapiens first emerged in Africa 500,000 years ago

Homo sapiens neandethalensis, a regional variety of Homo sapiens arose about 100,000 in Europe and western Asia

Homo sapiens sapiens emerged in Africa 100,000 years ago

45,000-40,000 years ago: Homo sapiens sapiens first moves out of Africa into southwestern Asia and Europe

20,000 years ago: Human habitation begins in the Francthi cave in southeastern Greece

10,000-8,000 B.C.: Transition from Paleolithic to Neolithic Age: the beginning of agriculture and permanent settlements

8,000 B.C.: Walled settlement at Jericho in ancient Palestine; Catal Huyuk (Turkey) founded more than 8,000 years ago; thriving community for a 1,000 years

7,000-6,000 B.C.: Agriculture and domestication of animals under way in southern and eastern Europe, including Greece

7,000-5,000 B.C.: Settlements of permanent houses being built in fertile plains in Greece

3500 B.C.: The Sumerians, the first civilization (group of cities) in Mesopotamia, the "Fertile Crescent." These people were not indigenous (local) to the area, but came from the Indus Valley, 1500 miles away.