BIOL 2P05 Lecture Notes - Lecture 1: Canine Tooth, Hominini, Molecular Clock
11 Apr 2017
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Document Summary
Hominini is the tribe of homininae that comprises humans (homo) and all ancestors of homo sapiens back to the split from the apes. This branching is now dated at 5 to 8 million years ago. The first hominins: differentiation trends from other hominids. Use of tools: the first thing that developed within our tribe is reduced size of canine teeth. Large canine teeth were used for male-to-male competition not for catching prey. Males (humans) are unable to tell when a woman is able to conceive unlike chimps. Males are forced to become providers and wait for when the woman is ready to conceive, unlike in chimps. Males (humans) guard females more often; no male-to-male competition: our increased brain size and skull size evolved 2nd last. Occurred slowly: increased childhood dependency occurred at the same time as our brain size increased, bipedalism is thought to be the consequence of climate change. Drier conditions caused negative effects on primates.
