BIOL 1108 Lecture Notes - Lecture 3: Genetic Drift, Natural Selection, Zygosity
Document Summary
Core concept 4: natural selection leads to adaptations, which enhance the fit between an organism and its environment. Adaptation: trait, leads to enhancement of organism in its environment (+: more reproduction. Non-adaptive: migration, mutation, genetic drift, non-random mating (sexual selection) Not natural selection: may not be well adapted to environment, alleles may not be as fit. Natural selection adaptation: some survive/reproduce better than others, leave more copies of their genome behind. Over time evolution: many generations, trait enhances survival/reproduction. Natural section is a cornerstone of modern evolutionary theory. Individuals in a population vary in their traits. Trait is not fixed, has to be variable, difference in different individuals: some of these differences are heritable, more offspring are produced than can survive, and only some of these will survive long enough to reproduce. An individual with a novel adaptation has evolved that adaptation: false: populations evolve, individuals do not, evolve: change in allele frequency over time in population.
