ANT 1 Lecture Notes - Lecture 19: Spina Bifida, Phenotype, Neural Tube Defect
Document Summary
Lecture 19: human genetic variation: review from last lecture: out-of-africa hypothesis, homo ergaster left africa (first migration, 1. 2-1. 8 mya) Evolved into homo erectus and possibly homo floresiensis in asia. Evolved into homo heidelbergensis and then homo neanderthalensis in europe and the middle east. The homo ergaster (and homo heidelbergensis?) who stayed behind in africa during the first migration evolved into. Homo sapiens, who then left africa again (second migration, 60 kya) and replaced all the other hominins in europe, 60 kya: people from one african population migrate to eurasia and australasia. 60 kya present: dispersed human populations diverge: when populations expand, local groups become isolated from each other and genetic differences begin to accumulate. Each subsequent founder effect further reduces variation: original populations contain the most variation. Populations furthest away from the original source contain the least variation: once you lose the variation, you can"t get it back.
