Human Origins • Origin of the human genus Homo is one of the most intriguing and controversial questions in paleo-anthropology. • The oldest fossils of our genus are at least 2.3 to 2.5 million years old.
Precursors of Modern Humans • Homo ergaster and Homo erectus (2 MYRS to 400,000 years ago (some researchers are ‘lumpers’ and some are ‘splitters’) • Homo sapiens neandertalensis (Neanderthals--200,000-35,000 years ago) • Homo sapiens sapiens (Modern Humans—ca. 40,000 years ago, although some early forms appear more than 200,000 years ago)
Why Africa? Why Then? • A period of environmental cooling and drying in Africa may have set the stage for the evolution of Homo. • Many types of animals suited to a drier environment originated between about 2.8 million and 2.4 million years ago, including the first species of Homo. • Toolmaking humans may have had an advantage in obtaining alternative food sources. • The new foods might have included underground tubers and roots and meat obtained through scavenging or hunting. • Brain enlargement, early stone tool use, and expansion of diet all may have been ways of adapting to fluctuating environments.
The First Neanderthals were found in alpine Neander Valley, Germany, in 1856
The Strange History of Neanderthals • Neanderthals lived in Alpine Europe beginning 200,000 years ago. • They were tough and highly adapted to freezing conditions, but disappeared around 30,000 years ago. • It’s always been thought that modern humans, moving into Europe from Africa somehow wiped them out - but the truth may be rather different.
The Levallois Tradition:Sophisticated Techniques, Efficient Tools • For thousands of years Neanderthals held the upper hand, before new technology, horrible environmental conditions, and sheer luck allowed modern humans to survive them.
Neanderthal Thinking:Honoring the Dead at Shanidar Cave, Iraq80,000 years ago
Whose Art?Much Cave Art Cannot be Firmly Attributed to H. sapiens sapiens
Ancient DNA and the H. sapiens sapiens – Neanderthal Debate • Several ancient Neanderthal remains have been typed and found to differ significantly from human mitochondrial DNA. • A team of scientists in Germany have recovered and sequenced Y-chromosome DNA from a 49,000 year-old Neanderthal.
Did Neanderthals and Homo Sapiens Sapiens Mate? • Some scientists argue that if there were widespread, successful matings among Neandertals and the ancestors of modern humans, then there would be contribution of Neandertal genetic sequences to the genomes of modern humans. • Others aren’t so sure. Perhaps a larger nu number of tested samples will yield different results.
A Good Source for the Controversy • http://www.indiana.edu/~ensiweb/dna.nean.html
Indonesian Flores Population ‘Hobbits” (until 13,000 BP) compared with Humans Elsewhere
The Multiregional Hypothesis:We are All Family Those people we call Homo erectus, Neanderthals and others along with Homo sapiens, formed a single species. This species arose in Africa two million years ago in the form called Homo erectus and spread out over the world, developing adaptations to regional conditions.