EEB 122 - Principles of Evolution, Ecology and Behavior

Lecture 04 - Natural Evolution: Genetic Drift. 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. (from

Lecture 04 - Natural Evolution: Genetic Drift

Time Lecture Chapters
[00:00:00] 1. Introduction
[00:04:56] 2. Genes and Amino Acid Changes Not Reflected in Phenotypes
[00:14:29] 3. Neutral Evolution in the History of Life
[00:20:38] 4. Mechanisms of Neutral or Random Evolution
[00:35:29] 5. The Molecular Clock of Neutral Evolution

Lecture 4 - Natural Evolution: Genetic Drift
Instructor: Stephen C. Stearns. Transcript [html]. Audio [mp3]. Download Video [mov].

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Lecture 01 - The Nature of Evolution: Selection, Inheritance, and History
Lecture 02 - Basic Transmission Genetics
Lecture 03 - Adaptive Evolution: Natural Selection
Lecture 04 - Natural Evolution: Genetic Drift
Lecture 05 - How Selection Changes the Genetic Composition of Population
Lecture 06 - The Origin and Maintenance of Genetic Variation
Lecture 07 - The Importance of Development in Evolution
Lecture 08 - The Expression of Variation: Reaction Norms
Lecture 09 - The Evolution of Sex
Lecture 10 - Genomic Conflict
Lecture 11 - Life History Evolution
Lecture 12 - Sex Allocation
Lecture 13 - Sexual Selection
Lecture 14 - Species and Speciation
Lecture 15 - Phylogeny and Systematics
Lecture 16 - Comparative Methods: Trees, Maps, and Traits
Lecture 17 - Key Events in Evolution
Lecture 18 - Major Events in the Geological Theatre
Lecture 19 - The Fossil Record and Life's History
Lecture 20 - Coevolution
Lecture 21 - Evolutionary Medicine
Lecture 22 - The Impact of Evolutionary Thought on the Social Sciences
Lecture 23 - The Logic of Science
Lecture 24 - Climate and the Distribution of Life on Earth
Lecture 25 - Interactions with the Physical Environment
Lecture 26 - Population Growth: Density Effects
Lecture 27 - Interspecific Competition
Lecture 28 - Ecological Communities
Lecture 29 - Island Biogeography and Invasive Species
Lecture 30 - Energy and Matter in Ecosystems
Lecture 31 - Why So Many Species? The Factors Affecting Biodiversity
Lecture 32 - Economic Decisions for the Foraging Individual
Lecture 33 - Evolutionary Game Theory: Fighting and Contests
Lecture 34 - Mating Systems and Parental Care
Lecture 35 - Alternative Breeding Strategies
Lecture 36 - Selfishness and Altruism