Principles of Evolution, Ecology and Behavior

Yale Course , Spring 2009 , Prof. Stephen C. Stearns

Lecture 9: The Evolution of Sex

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Lecture Details :

Principles of Evolution, Ecology and Behavior (EEB 122)

There are several explanations for the evolution of sex and its continued prevalence. One is facilitating the spread of helpful mutations while hastening the removal of harmful ones. Another is expediting resistance against pathogens. Sex does have several costs compared to asex, such as only giving half your genome to offspring, having to find mates, and the risk of predation and STDs. Overall, the benefits outweigh the costs and sex has a firm hold on the majority of the recent branches of the tree of life.

00:00 - Chapter 1. Introduction
08:54 - Chapter 2. The Traditional View on Sex’s Existence
13:38 - Chapter 3. The Costs of Sex
28:02 - Chapter 4. Recombination
38:25 - Chapter 5. Pathogens and Parasites
44:54 - Chapter 6. Modern Asexuality and Conclusion

Complete course materials are available at the Open Yale Courses website:

This course was recorded in Spring 2009.

Course Description :

The Nature of Evolution: Selection, Inheritance, and History - Basic Transmission Genetics - Adaptive Evolution: Natural Selection - Neutral Evolution: Genetic Drift - How Selection Changes the Genetic Composition of Population - The Origin and Maintenance of Genetic Variation - The Importance of Development in Evolution - The Expression of Variation: Reaction Norms - The Evolution of Sex - Genomic Conflict - Life History Evolution - Sex Allocation - Sexual Selection - Species and Speciation - Phylogeny and Systematics - Comparative Methods: Trees, Maps, and Traits - Key Events in Evolution - Major Events in the Geological Theatre - The Fossil Record and Life's History - Coevolution - Evolutionary Medicine - The Impact of Evolutionary Thought on the Social Sciences - The Logic of Science - Climate and the Distribution of Life on Earth - Interactions with the Physical Environment - Population Growth: Density Effects - Interspecific Competition - Ecological Communities - Island Biogeography and Invasive Species - Energy and Matter in Ecosystems - Why So Many Species? The Factors Affecting Biodiversity - Economic Decisions for the Foraging Individual - Evolutionary Game Theory: Fighting and Contests - Mating Systems and Parental Care - Alternative Breeding Strategies - Selfishness and Altruism

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