Biology Exam 2 Study guide
evolution The phenomenon that populations of organisms change over the course of many generations. As a result, some organisms become more successful at survival and reproduction
natural selection The process that eliminates those individuals that are less likely to survive and reproduce in a particular environment, while allowing other individuals with traits that confer greater reproductive success to increase in numbers.
Directional selection is when natural selection favors a specific phenotype over the other.
Stabilizing selection is when natural selections tries to favor an intermediate phenotype, therefore, the extreme's are targeted towards the two species.
Disruptive selection is when natural selection favors both phenotypes and typically eliminates the middle phenotype; hence, you end up with 2 different species. fitness The relative likelihood that a genotype will contribute to the gene pool of the next generation as compared with other genotypes. adaptations The processes and structures by which organisms adjust to changes in their environment. sexual selection A type of natural selection that is directed at certain traits of sexually reproducing species that make it more likely for individualsto find or choose a mate and/or engage in successful mating. gradualism A concept suggesting that species evolve continuously over long spans of time. punctuated equilibrium A concept that suggests that the tempo of evolution is more sporadic than gradual. Species rapidly evolve into new species followed by long periods of equilibrium with little evolutionary change. genetic drift The random change in a population’s allele frequencies from one generation to the next that is attributable to chance. It occurs more quickly in small populations. bottleneck effect A situation in which a population size is dramatically reduced and then rebounds.
While the population is small, genetic drift may rapidly reduce the genetic diversity of the
natural selection The process that eliminates those individuals that are less likely to survive and reproduce in a particular environment, while allowing other individuals with traits that confer greater reproductive success to increase in numbers.
Directional selection is when natural selection favors a specific phenotype over the other.
Stabilizing selection is when natural selections tries to favor an intermediate phenotype, therefore, the extreme's are targeted towards the two species.
Disruptive selection is when natural selection favors both phenotypes and typically eliminates the middle phenotype; hence, you end up with 2 different species. fitness The relative likelihood that a genotype will contribute to the gene pool of the next generation as compared with other genotypes. adaptations The processes and structures by which organisms adjust to changes in their environment. sexual selection A type of natural selection that is directed at certain traits of sexually reproducing species that make it more likely for individualsto find or choose a mate and/or engage in successful mating. gradualism A concept suggesting that species evolve continuously over long spans of time. punctuated equilibrium A concept that suggests that the tempo of evolution is more sporadic than gradual. Species rapidly evolve into new species followed by long periods of equilibrium with little evolutionary change. genetic drift The random change in a population’s allele frequencies from one generation to the next that is attributable to chance. It occurs more quickly in small populations. bottleneck effect A situation in which a population size is dramatically reduced and then rebounds.
While the population is small, genetic drift may rapidly reduce the genetic diversity of the