Modern Humans continued

1
Modern Humans continued
2
(No Transcript)
3
Genetic and morphological evidence
4
Genetic evidence
12 Neandertals 7 archaic H.sapiens
3,000 base pairs
5
Spread of modern humans
6
North American Paleo-Indians
Kennewick, Washington 8,400 y
Warm Mineral Springs, Florida 10,000 y
7

• Human diversity

How is human diversity perceived? Traditionally
as distinctly different races
8

• Many attempts to classify human diversity
• Linnaeus. 1758. Systema Naturae
• Homo sapiens afer (Africans)
• Homo sapiens americanus (Native Americans)
• Homo sapiens asiaticus (Asians)
• Homo sapiens europaeus (Europeans)
• Homo sapiens ferus (Wild Men)
• Carleton Coon. 1965. The Living Races of Man
• Caucasoid
• Mongoloid
• Australoid
• Congoid
• Capoid

9

• Races in non-human species.
• 1. A biological race a subspecies.
• Phenotypically diagnosable populations occupying
  a subdivision of the range of a species.
• These populations have be exposed to different
  selection pressures.
• Therefore, they express a restricted set of
  adaptations
• 2. Human race concept.
• There is no satisfactory biological definition of
  a human race!
• Misconception there are character states unique
  to particular groups of humans
• The characters traditionally used are
  quantitative characters with continuous
  variation.

10
Racial characters are quantitative
characters continuous characters e.g. skin
color Phenotypic expression in and among
populations generally fits a normal distribution
11
Skin pigmentation as a racial characteristic.
12
These groups easy to identify because of
non-overlapping variation.
Gaps
(685 nm)
13
Skin color in 22 human populations Samples of
males Mean /- one standard deviation
14
Global Patterns of Human Variation

• Can be examined genetically
• Can be examined phenotypically
• Are phenotypic differences concordant with
  genetic differences?

15
Eight classes of genetic similarity enzyme
blood group loci Arrayed by increasing difference
Distribution of eight classes of skin
pigmentation intensity
Concordance or discordance?
16

• Today, human races are distinguished by ethnic
  differences NOT biological differences.
• Differences in culture
• nationality
• language
• Religion
• Biological differences are still mistakenly
  emphasized, even Sociology Departments e.g. a
  person of color.