Biology 1001A Lecture Notes - Lecture 14: Gene Flow, Population Bottleneck, Aposematism
Document Summary
Selection on quantitative traits: stabilizing, directional, disruptive, stabilizing is the most common, the extreme phenotype gets selected against, directional, the population at one extreme end will have better survival rates. Selection pressure varies over time, and across habitats: selective advantage for a population at one environment than other environments that"s why there are many variations in the wild, adaptations (traits that increase bearer"s relative fitness) are environment-specific. E. g. predators form search images of prey these predators will remember the image of the prey which ones taste good, they only select against this one type of prey. When one type becomes very little (rare), the predator will change their preference and start selecting against the more common prey. so that with this the allele frequency will stay 50 - 50 ratio. Maintain multiple alleles, indefinitely, selection cannot remove a type of allele.
