ANTA01H3 Lecture Notes - Lecture 2: Bighorn Sheep, Bowerbird, Porphyria
Document Summary
Evolution does not rely solely on a particular mechanism or praceess. Smallest unit of time in which evolution occurs is a generation. Niche: role of a species in its environment (eg) galapos island. Selection by humans for favorable traits: sexual selection. Selection on feathers or behavior associated with mating. Female choice (eg. female bower bird inspecting a bower) Male choice is not very important because sperm is cheap: non-random mating more associated with humans. Mutation: a change in dna can refer to change in dna bases as well as changes in chromosome # or structure. Could be the first step in process of speciation: founders effect: differences in the frequency of variants in a population as a result of random chance in which members start a new population. One outcome of founders effect can be the increase in the relative frequency of a rare type (eg. a gene for a disease such as porphyria)
