2.  Most scientists date Earth’s origin to around 4.5 billion years ago  222 million years ago, mammals first appeared  200 mya-65 mya dinosaurs roamed the Earth  65 mya- first primates  4.5 million years ago- first possible human ancestor appeared

3.  All information on pre-history human ancestors comes from fossil finds of skulls and bones  Most recent findings came in 1994 when new bones were found in Ethiopia and new species was discovered: Ardipithecus ramidus

4.  Lived 4.4 mya  Cranium the size of present day chimp  Found near present day Ethiopia  Diet included mostly nuts and vegetation

5.  Believed to have been 4 species  Lived 3.5 mya  Walked on 2 legs (hole in bottom of head that spinal column goes into)  Short, hunched over but walked upright  Small brain (size of baseball)  Molars have heavy enamel- more diverse diet  Sexual dimorphism  Altricial infants- children that require a lot of care when born

7.  Homo Habilis – “handy man” 2.5 mya- 1.8 mya 2 subgroups- smaller and larger Rounded skull, bones are thinner Large canines Earliest known to use stone tools. Known as Oldowan tools Found in East and South Africa

9.  1.7 mya -.5 mya  Increase in brain size (2x Australopith)  Shortened face (beginning of chins)  Size increases (males up to 5’10”)  Sexual dimorphism decreased  Use of different tools like hand-axe (Archeulian)  Discovered fire  First to hunt for subsistence

11.  First hominines out of Africa are Homo erectus  First use of fire (700,000 yrs ago)  Ate meat – more scavenging than hunting  Smaller pelvis = smaller babies

12.  Significant increase in brain size  Less robustivity  Increase in tool sophistication  Bones found all over most of the Old World  Still shorter than modern humans  Mousterian tools  Hunters  Thought to have possibly buried dead and have some form of organized religion and language

13.  Appeared 35,000 yrs ago  Taller than all other Homines  Less robust  Rounded skull  Higher, less sloped forehead  Relatively cultured  Extensive tool use

14.  Art  Body decoration  Demise of large animals all around the world  Cultural explosion