Lecture 11 Genus Homo- Earlier Species
*In the Pliocene, the climate shifted cooler & drier
*This made food increasingly seasonal, tough and difficult to find
*Two forms of Australopithecines seem to have adapted differently:
-Robust species- morphologically (larger teeth, bones, muscles) via
specializing in diets of seeds and nuts
-Gracile species- behaviorally via wider dietary diversity- they probably gave
rise to the genus Homo
The Genus: Homo
*Evolved 3-2.5mya
*Bigger brains
-Tool use
-Hunting
-Complex social behavior
-Control of fire
*Species: habilis, erectus, heidelbergensis, neanderthalensis, sapiens
Homo habilis, 2.5-1.6mya
*”Handy man”
*First discovered by Louis Leakey at Olduvai Gorge, but specimens found in East and South
Africa
*Postcranial similarities to A. africanus, but cranially different:
-larger brain (650 cc)
-smaller teeth
-less prognathic face
*Immediate ancestor of habilis unconfirmed
-Tim White suggests A. garhi
*H. habilis lived when grasslands were spreading (increasing habitat diversity)
*Skull and tooth morphology suggest dietary variability in Homo habilis
-adaptive flexibility
*H. habilis used Oldowan tools
-Tools are found in association with habilis
-Today, it is widely accepted that habilis as the first hominid species
purposefully made and used stone tools
*Tools became fundamental to survival, unlike for australopithecines
*Stone tools important for obtaining food resources as well as for processing foods
-H. habilis were probably scavengers rather than hunters, assessed from faunal
evidence
Oldowan Tools *Two tools types:
-flakes
-hammer stones
*Cutting, chopping, and crushing
*Meat processing
*Evidence of Butchering in Faunal Remains
-Animal teeth marks are often present underneath cut marks. What does this imply?
Homo habilis had camp sites
*High density of tools indicates camp sites used by habilis
*Same places for extended periods of time
*This is clearly different from what we see in living non-human primates
Homo erectus, 1.8-0.3mya
*”Upright man”
*First discovered by Eugene Dubois in Java, but specimens are found in Africa, Asia and Europe
*Cranial capacity average 950cc
Evolution of H. erectus
*African fossils are the more robust than Asian or
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