Evolution of human intelligence

The evolution of human intelligence is closely tied to the evolution of the human brain and to the origin of language. The timeline of human evolution spans approximately seven million years,^[1] from the separation of the genus Pan until the emergence of behavioral modernity by 50,000 years ago. The first three million years of this timeline concern Sahelanthropus, the following two million concern Australopithecus and the final two million span the history of the genus Homo in the Paleolithic era.

Many traits of human intelligence, such as empathy, theory of mind, mourning, ritual, and the use of symbols and tools, are somewhat apparent in great apes, although they are in much less sophisticated forms than what is found in humans like the great ape language. The cognitive tradeoff hypothesis proposes that there was an evolutionary tradeoff between short-term working memory and complex language skills over the course of human evolution.

^ Klug WS, Cummings MR, Spencer CA, Palladino MA (2012). Concepts of Genetics (Tenth ed.). Pearson. p. 719. ISBN 978-0-321-75435-6. Assuming that chimpanzees and humans last shared a common ancestor about 8-6 million years ago, the tree shows that Neanderthals and humans last shared a common ancestor about 706,000 years ago and that the isolating split between Neanderthals and human populations occurred about 370,000 years ago.

[1] Klug WS, Cummings MR, Spencer CA, Palladino MA (2012). Concepts of Genetics (Tenth ed.). Pearson. p. 719. ISBN 978-0-321-75435-6. Assuming that chimpanzees and humans last shared a common ancestor about 8-6 million years ago, the tree shows that Neanderthals and humans last shared a common ancestor about 706,000 years ago and that the isolating split between Neanderthals and human populations occurred about 370,000 years ago.

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