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Lec 4 - Neutral Evolution: Genetic Drift

"Lec 4 - Neutral Evolution: Genetic Drift" Principles of Evolution, Ecology and Behavior (EEB 122) Neutral evolution occurs when genes do not experience natural selection because they have no effect on reproductive success. Neutrality arises when mutations in an organism's genotype cause no change in its phenotype, or when changes in the genotype bring about changes in the phenotype that do not affect reproductive success. Because neutral genes do not change in any particular direction over time and simply "drift," thanks in part to the randomness of meiosis, they can be used as a sort of molecular clock to determine common ancestors or places in the phylogenetic tree of life. 00:00 - Chapter 1. Introduction 04:56 - Chapter 2. Genes and Amino Acid Changes Not Reflected in Phenotypes 14:29 - Chapter 3. Neutral Evolution in the History of Life 20:38 - Chapter 4. Mechanisms of Neutral or Random Evolution 35:28 - Chapter 5. The Molecular Clock of Neutral Evolution Complete course materials are available at the Open Yale Courses website: http://open.yale.edu/courses This course was recorded in Spring 2009.

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Lecture list for this course

Lec 1 - The Nature of Evolution: Selection, Inheritance, and History

Lec 2 - Basic Transmission Genetics

Lec 3 - Adaptive Evolution: Natural Selection

Lec 5 - How Selection Changes the Genetic Composition of Population

Lec 6 - The Origin and Maintenance of Genetic Variation

Lec 7 - The Importance of Development in Evolution

Lec 8 - The Expression of Variation: Reaction Norms

Lec 9 - The Evolution of Sex

Lec 10 - Genomic Conflict

Lec 11 - Life History Evolution

Lec 12 - Sex Allocation

Lec 13 - Sexual Selection

Lec 14 - Species and Speciation

Lec 15 - Phylogeny and Systematics

Lec 16 - Comparative Methods: Trees, Maps, and Traits

Lec 17 - Key Events in Evolution

Lec 18 - Major Events in the Geological Theatre

Lec 19 - The Fossil Record and Life's History

Lec 20 - Coevolution

Lec 21 - Evolutionary Medicine

Lec 22 - The Impact of Evolutionary Thought on the Social Sciences

Lec 23 - The Logic of Science

Lec 24 - Climate and the Distribution of Life on Earth

Lec 25 - Interactions with the Physical Environment

Lec 26 - Population Growth: Density Effects

Lec 27 - Interspecific Competition

Lec 28 - Ecological Communities

Lec 29 - Island Biogeography and Invasive Species

Lec 30 - Energy and Matter in Ecosystems

Lec 31 - Why So Many Species? The Factors Affecting Biodiversity

Lec 32 - Economic Decisions for the Foraging Individual

Lec 33 - Evolutionary Game Theory: Fighting and Contests

Lec 34 - Mating Systems and Parental Care

Lec 35 - Alternative Breeding Strategies

Lec Last - Selfishness and Altruism