Exam 7: Evolution and Adaptation　

Consider three populations of a plant species, each isolated from other populations of the same species. Population X has contained approximately 100 individuals in each generation for the past 200 generations. Population Y has contained approximately 10,000 individuals in each generation for the past 200 generations. Population Z has contained approximately 1 million individuals in each generation for the past 200 generations. If genetic drift is the only evolutionary process acting on these populations, how can we expect the amount of genetic variation to differ among these populations?

A group of island birds have beaks that are on average 20 mm long with a standard deviation of 1 mm. Beak length is a genetically based trait with a heritability of 0.5. Only small seeds are available for these birds to consume, and some of the large-beaked birds are unable to reproduce. The group of birds that successfully reproduces has an average beak size of 16 mm. Based on this information, predict how much the beak size is expected to change in the next generation.

The drastic phenotypic differences between large dogs, such as bloodhounds, and small dogs, such as Chihuahuas, are a result of

Which of the following is a necessary component of allopatric speciation?

Which of the following is/are correct? I. Sympatric speciation occurs without geographic barriers. II. Sympatric speciation can occur through polyploidy. III. Sympatric speciation is less common than allopatric speciation.

The evolution of pesticide resistance in insects is an example of

Consider a gene that affects fur color in mice. This gene has two alleles, A and a. If AA mice have white fur, Aa mice have gray fur, and aa mice have black fur, how would we describe the effect of these alleles?

What is the term for evolution that acts at the level of species, genera, and higher levels of organization?

A trait that is determined by multiple genes is referred to as

What term describes making new combinations of alleles using existing genetic variation when gametes are formed?

For mutations that enter a population of a diploid organism, which type of mutation is most likely to be affected by natural selection when it first appears?

How might understanding microevolution have a direct benefit to humans in the fight against diseases?

The phenomenon by which moths in England evolved from light-colored forms to dark-colored forms over several decades is known as

If climate change were to cause a tree with very dark bark to become common in England, what would we expect to happen to the color patterns of the peppered moth, and why would we expect it to happen?

The human activity of controlling the survival and reproduction of organisms to produce offspring with specific sets of traits is known as

What term refers to the alleles of all the genes of every individual in a population?

When one gene controls the expression of another gene, this is called

When a phenotype is under disruptive selection, which parts of the phenotypic distribution are expected to have the highest fitness?

A small species of fly lays its eggs in plant stems. The developing fly larvae cause a gall, or large round structure, to form in the stem. Genetic differences among flies cause variation in the size of the galls they produce. Both birds and wasps feed on the larvae in the galls. The proportions of small, medium, and large galls able to survive attacks by either birds or wasps are shown in the table. If a population of flies lives in a field with equal abundance of birds and wasps, will gall size be by directional, stabilizing, or disruptive selection? Explain your answer. Gall size () Gall survival with birds (\%) Gall survival with wasps (\%) 15 100 25 20 100 100 25 25 100

Describe the difference between synonymous and nonsynonymous mutation. Which type is more likely to be affected by natural selection, and why?