Lecture on Genetic Variation and Race

Key Figures and Concepts

Richard Lewontin
- Concerned with measuring genetic variation within and between human groups.
- Conducted pioneering work in genetics in the 1960s using gel electrophoresis.
- Investigated genetic differences across races using data collected by anthropologists and geneticists.

85% of Genetic Variation
- The majority (85%) of genetic variation occurs between individuals within the same local population (e.g., Swedes, Chinese, Kuikuru, Icelanders).
- There is as much genetic difference between two individuals of the same race as between individuals of different races.
Implications of Lewontin’s Work
- Genes do not correlate strongly with racial categories.
- "Black" and "White" individuals are not genetically more similar within their groups than across these racial categories.
- More diversity exists within racial groups than between them.

Greater Emphasis on Geography
- Genetic differences are more accurately explained by geography rather than race.
- Accumulation of certain genes can occur in specific geographic locations.

Origin and Migration
- Human lineage started in Africa.
- Two major migrations:
  - First migration out of Africa by early hominids, but these lineages died out (e.g., Neanderthals and Homo Erectus).
  - Second migration of Homo sapiens less than 100,000 years ago led to all modern humans today.
Modern Human Migration
- Movements due to agriculture and other migrations, such as crossing the Bering Strait to the Americas.
- Genetic mixing and reassortment over approximately 100,000 years.

Evolutionary Perspective
- 100,000 years is short in evolutionary terms, insufficient for the development of distinct sub-species.
- Variation mainly in superficial features (e.g., skin color, hair form).
Conclusion
- Humans are effectively genetically similar beneath superficial differences.
- Visual differences are misleading, contributing to misconceptions about race.