BIO SCI 94 Lecture Notes - Lecture 18: Human Taxonomy, Toba Catastrophe Theory, Population Bottleneck

• School: UC-Irvine
• Department: Biological Sciences
• Course: BIO SCI 94
• Professor: Nancy Burley

Document Summary

Finish up human evolution and start on human population growth. Mitochondrial dna is only transmitted by the mother, and the y-chromosome dna is only transmitted by the father. Greatest grandmother lived in africa about 200-150 kya. Y-mrca = y-chromosome adam can also be traced to africa in 150 - 250 kya. Neanderthal dna can be excluded as ancestral to our dna. Mt-dna and y-dna are very useful for tracing human migrations. There were 2 out of africa events that led to the homo sapiens. There was a genetic bottleneck event that occurred 60,000-75,000 ya. There should be more genetic diversity than there is today. We don"t specifically know, expect that there is a volcanic occurrence that may have caused this mt. Not a mass extinction event, but just a loss of many life. This was a 6 year volcanic winter. Maybe only 15,000 people survived -- mostly in africa. Homo sapiens sapiens radiated in different places .