BIOL 3300 Lecture Notes - Ecological Selection, Allele Frequency, Selective Breeding
Document Summary
Locus: position on chromosome, may correspond to a gene. Allele frequency: proportion of specific allele in population. Genotype frequency: proportion of individuals with specific genotype. Required: variation, heritable trait, differential fitness (ability to survive & reproduce, reproduction. Other mechanisms: genetic drift, gene flow, non-random mating, mutation. Two types: ecological selection, ex: predators (peppered moth), food, sexual selection (variety of types, ex: competition for mates (inter & intra specific) No proper flower development with mutations at cauliflower. As a result of selection by bees, evolution occurred over 1 generation. In f1 white flower was being selected for. Have to look at strength of selection and what is being selected for or against. Looking at beak depth in finches: bigger beak can crack harder seeds. Salmon size decreasing over the years, therefore eggs produced decrease: selection against larger size fish. Have small or large bills; feed on different sage according to beak size (soft/hard seeds) Historical constraints: ex: giraffe neck length.