Exam 18: Evolution of Populations

A used car is shipped from Australia to the United States. Stowed away in the trunk of the car is a piece of wood infected with Australian termites. Once in the United States, the buyer of the car finds the rotting wood and dumps it on the side of the road. The termites survive and establish a colony on the side of the road, but do not mate with local termite populations. This is an example of

Disruptive selection operates whenever

Is the effect of an individual permanently leaving a population likely to have a greater genetic effect if the home population was large or if the home population was small?

In the figure below, the flying bird moves permanently into the population shown on land. As a result, the allele frequency of A in the population changes from

Which of the following statements concerning evolution is false?

The bell-shaped curve at the top of the figure below shows the distribution of a phenotype in a population at the start of an experiment. The three graphs (lettered A-C)beneath predict what the distribution will look like if a certain type of selection occurs. Which graph represents what the phenotypic distribution will look like if the population undergoes stabilizing selection?

Microevolution

Larger male elephant seals have more mates than smaller male elephant seals because they are better at defending their territory (and mates). This is an example of ____________________.

If the genotype values predicted by the Hardy-Weinberg equation are greatly different from the values found in the real population, we can say that the population is ____________________.

What is the total number of alleles present for any given gene in a population of 100 individuals?

If a given population has 30 RR individuals, 10 Rr individuals, and 10 rr individuals, what is the genotype frequency of Rr?

A student with Strep throat (caused by a strain of bacterium)is given a prescription for an antibiotic and is told to take the drug for two weeks. After a week, the student feels better and stops taking the drug. Two months later, the student again shows symptoms of Strep throat and decides to finish the leftover antibiotic rather than going to the doctor again. Two months later, the student develops Strep throat for a third time and returns to the doctor. This time, the antibiotic does not work. The doctor runs a test and discovers that the bacterial strain the student is carrying is antibiotic resistant. What most likely happened?

A few members of a species establish themselves on a small island far from other populations of that species. They may experience a genetic bottleneck due to the ____________________ effect.

Which of the following is not a step in the evolutionary process?

In ____________________ selection, individuals with one extreme of an inherited phenotypic trait have an advantage over other individuals in the population.

One factor that complicates the treatment of AIDS is the

Although they are protected in many countries, humans still hunt elephants for their ivory tusks. A mutation that results in tuskless elephants is increasing in frequency in some elephant populations as a result of the evolutionary mechanism of ____________________.

A scientist is studying beak length in a species of hummingbird. The scientist establishes a population of birds with beaks ranging from very small to very long and allows the population to breed for 10 years. At the end of the experiment, she finds that the majority of birds in the population have very long beaks. This is an example of _____ selection.

If p is the frequency of the W allele in a population, why do we equate the WW individuals with the p² portion of the Hardy-Weinberg equation?

A fisherman catches one trout from each of two ponds. Pond A contains 100 trout and pond B contains 1,000 trout. Which population is more affected by the fisherman?