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 oyc.yale.edu)
| 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 |
| References |
| Lecture 4 - Natural Evolution: Genetic Drift Instructor: Stephen C. Stearns. Transcript [html]. Audio [mp3]. Download Video [mov]. |
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