AN202 Lecture Notes - Lecture 18: Human Y-Chromosome Dna Haplogroup, Balancing Selection
Document Summary
Patterns of variation: recent studied of human variation indicate that: Most variation in traits is clinical: cline: gradual differences across an area, few sharp boarders in traits between human populations, most groups similar to nearby groups, reflects the effects of gene flow. Most traits vary independently: reflects independent inheritance, different selective pressures, populations could be groups in different ways using different traits, mtdna and y-dna variation an be use to group relationships. All human groups appear to share a relatively recent common ancestor smaller and more closed related groups may share some typical traits reflects recent common ancestry. They still show much more internal variation: most genetic variation is seen within racial groups. Variation between racial groups accounts for relatively small % of total human variation .
