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______ is the original source of new alleles. a. Mutation b. Natural selection c. Genetic drift d. Gene flow e. Speciation f. Microevolution

Which is required for evolution to occur in a population? a. genetic diversity b. selection pressure c. gene flow d. none of the above

Match the pattern of natural selection with its best description. stabilizing disruptive a. eliminates extreme forms of a trait b. eliminates mid-range forms of a trait

Sexual selection frequently influences aspects of body form and can lead to _____. a. a sexual dimorphism b. male aggression c. exaggerated traits d. all of the above

The persistence of the sickle allele at high frequency in a population is a case of _____ a. bottlenecking b. balanced polymorphism c. the founder effect d. inbreeding

______ tends to keep populations similar to one another. a. Genetic drift b. Gene flow c. Mutation d. Natural selection

The theory of evolution by natural selection does not explain ______. a. genetic drift b. the founder effect c. gene flow d. how mutations arise e. inheritance f. any of the above

Which of the following is not part of how we define a species? a. Its individuals appear different from other species. b. It is reproductively isolated from other species. c. Its populations can interbreed. d. Fertile offspring are produced.

Which of the following statements is correct? a. Genetic drift occurs only in small populations. b. Inbreeding increases genetic diversity. c. Gene flow can reintroduce alleles into a population.

After fire devastates all of the trees in a wide swath of forest, populations of a species of treed welling frog on either side of the burned area diverge to become separate species. This is an example of ______ a. allopatric speciation b. adaptive radiation c. an evolutionary bottleneck d. genetic drift