BIO SCI 94 Lecture Notes - Lecture 4: Genotype Frequency, Allele Frequency, Stabilizing Selection

• School: UC-Irvine
• Department: Biological Sciences
• Course: BIO SCI 94
• Professor: Nancy Aguilar- Roca

Document Summary

Front legs of a mouse and the wings of a bat. If a population is in hardy-weinberg equilibrium then . Observed genotype frequencies are similar to predicted genotype frequencies. True for a highly inbred population that does not violate hardy-weinberg equilibrium Frequency of homozygotes increases allele frequencies do not change. Forces the average to move one way or another. Genotype frequencies do not match hardy-weinberg assumptions. May lead to loss of an allele (freq=0) or fixation (freq=1) **bigger population = less likely for the allele to be lost of fixed. When a small number of alleles leave the population. ** small populations result in more genetic drift. Reproductive isolation - prezygotic barriers (prevents egg and sperms to come together) Behavior that only that species finds attractive. Ex. penis size must match up with mates. Due to protein in sperm that does not match up with the egg and therefore cannot be fertilized. Prevents hybrid developing into viable, fertile adult.