10: genus homo
DESCRIPTION
Genus HomoTRANSCRIPT
Genus Homo
• Hominin = a habitually bipedal primates.
Early Hominins
• All the early hominins were found in Africa. They all were relatively small brained and used comparatively simple technology.
Emergence of Genus Homo
• Around 2.2 million years ago, we start seeing the emergence of Genus Homo in Africa.
Genus Homo: the generalities
• Larger brains than Early Hominins
• Skulls are less ape-like.
• More complex culture, including the use of stone tools.
Homo habilis
• Homo habilis (literally: handy man) is one of the earliest members of Genus Homo to be identified.
• Despite having a larger brain then earlier hominins, Homo habilis still had archaic features.
Archaic Features
• Brow Ridges
• Sloping Forehead
• Prognathism
• Lack of a chin
Homo habilis
• Had an average brain size of around 680ml, nearly 50% larger than previous hominins.
• First fossil we associate with the use of stone tools.
Homo habilis skull (left)vs. Australopithecus (right)
Stone Tools
Homo ergaster 1.9-1.4 mya
• Homo ergaster is a possible ancestor of Homo erectus and possibly also an ancestor of Homo heildebergensis.
Homo erectus 1.8 mya to 50,000 years ago.
Homo erectus
• Larger brain: 1000ml on average (and as large as 1250ml).
• Prominent brow ridges and prognathism
Migration
• Homo erectus is widely believed to be the first hominin to migrate out of Africa.
“Tuang Child” Endocast
Endocast Reconstruction of Homo erectus
Brain Regions
Speech
• The bones attached to the larynx and pharynx indicate Homo erectus had the ability to make the sounds necessary for speech…
• Furthermore the neural structures for speech production and recognition are present in the brains of Homo erectus.
Homo heidelbergensis
• Found about 400-600,000 years ago
• Was possibly the first hominin to bury their dead.
• May be the direct ancestor of both Homo sapiens and Neanderthals.
Homo neanderthalensis
• Homo neanderthalensis or Neanderthals: between 225,000 and 28,000 years ago.
• Neanderthals lived through the Pleistocene a period characterized by a series of glacial advances (Ice Age).
Neanderthals
• Large brains• Heavy brow ridges
and sloping forehead
• Built heavier and stockier than contemporary humans
Neanderthal Adaptations to the Cold
• Short, stocky bodies: conserved heat in the core.
• Long, broad noses would have warmed the cold air that they inhaled.
Humans vs. Neanderthal
Interbreeding?
• There is evidence that the majority of people of non-African origin have between 2 and 4% Neanderthal DNA.
• This would imply, of course, that modern humans and Neanderthals were the same species. They should be referred to as Homo sapiens sapiens and Homo sapiens neanderthalensis.
Modern Humans
• Modern Humans (Homo sapiens) probably emerged around 150,000 years ago.
• Have flat faces• Lack heavy brow ridges• Have “globular” skulls rather than
elongated ones.• Presence of a chin
Modern Humans
• The earliest anatomically modern humans are found in Africa.
Modern Human Skull
Bering Strait Land Bridge