ENVS200 Chapter Notes - Chapter 4: Allele Frequency, Species, Pollen Tube
Document Summary
Physical and ecological processes interact with selection and drift to produce new species. Natural selection and genetic drift are two mechanisms that can cause dramatic changes in gene frequencies within a population. Such evolutionary changes have obvious implications for interactions among individuals within the larger ecological community. For example, selection toward larger body size in a predator may alter the intensity of predation experienced by the prey. What we have not yet discussed is what happens over even longer time scales, where large changes in gene frequencies can result in the evolution of a new species. Species are the raw material for all ecological interactions, and thus any process that can alter the rate of speciation has significant ecological consequences. In this section we will discuss a variety of mechanisms that can cause speciation. However, before we can discuss how species evolve, we must first have an understanding of what we mean by species.
