occurs when individuals move into or out of a population, changing the allele frequencies in the population. In this case, new brown beetles in the population cause the frequency of the brown allele to increase.
occurs when organisms with one inherited trait survive and reproduce more than organisms with other traits.
favors intermediate phenotypes, selecting against phenotypes at both ends of a range and reducing variation
favors phenotypes at one end of a range and is common in periods of environmental change.
favors phenotypes at one end of a range and is common in periods of environmental change
individuals with certain inherited characteristics are more likely to obtain mates than other individuals.