Question 1

Which of the following processes is the only one that consistently leads to adaptive evolution in a population?

Accepted Answer

Natural selection

Question 2

A population of birds is isolated on an island. Over time, a hurricane drastically reduces the population size, leaving only a few survivors. Which evolutionary process is most likely to have a significant effect on allele frequencies in this scenario?

Accepted Answer

Genetic drift (bottleneck effect)

Question 3

Which of the following is a correct statement about the Hardy–Weinberg equilibrium?

Accepted Answer

It serves as a null hypothesis for studying evolutionary processes.

Question 4

In a population, the frequency of allele A is $$p = 0.6$$ and the frequency of allele a is $$q = 0.4. $$According to the Hardy–Weinberg equation $$p^2 + 2pq$$ + $$q^2 = 1$, what is the expected frequency of heterozygotes?

Accepted Answer

$$0.48$$

Question 5

Which of the following best describes the effect of inbreeding on a population?

Accepted Answer

It increases homozygosity and can lead to inbreeding depression.

Question 6

A population of fish is split by a dam, and over time, the allele frequencies in the two groups become more different. Which evolutionary process is most likely responsible for this divergence?

Accepted Answer

Genetic drift

Question 7

Which of the following is an example of directional selection?

Accepted Answer

Finch beak depth increasing after a drought

Question 8

Which mode of selection is most likely to maintain genetic variation in a population?

Accepted Answer

Balancing selection

Question 9

A population of plants is exposed to a new herbicide. After several generations, only individuals with a rare allele survive and reproduce. This is an example of:

Accepted Answer

Directional selection

Question 10

Which of the following statements about mutation is correct?

Accepted Answer

Mutation is the primary source of new alleles in a population.

Question 11

In a population of 1000 individuals, 360 are homozygous dominant (AA), 480 are heterozygous (Aa), and 160 are homozygous recessive (aa). What is the frequency of allele A?

Accepted Answer

$$0.6$$

Question 12

Which of the following is an example of intersexual selection?

Accepted Answer

Female birds choosing mates with the brightest feathers

Question 13

Which evolutionary process is most likely to decrease genetic differences between two populations?

Accepted Answer

Gene flow

Question 14

A population of beetles has two color morphs: green and brown. Birds learn to recognize and eat the most common color. Over time, the rare color increases in frequency. This is an example of:

Accepted Answer

Frequency-dependent selection

Question 15

Which of the following is NOT an assumption of the Hardy–Weinberg equilibrium?

Accepted Answer

Nonrandom mating

Question 16

Which of the following best explains why purebred dogs often suffer from inherited diseases?

Accepted Answer

Inbreeding increases homozygosity of deleterious alleles

Question 17

A group of lizards colonizes a new island. The allele frequencies in this new population differ from the original population. This is an example of:

Accepted Answer

Founder effect

Question 18

Which of the following is a consequence of stabilizing selection?

Accepted Answer

Reduction in both extremes of a trait

Question 19

Which process is most likely to result in the fixation of a neutral allele in a small population?

Accepted Answer

Genetic drift

Question 20

Which of the following is a real-world example of inbreeding depression?

Accepted Answer

Reduced survival and fertility in Florida panthers

Evolutionary Processes: Mechanisms of Evolution and Their Effects on Populations

Study Guide - Practice Questions

Study Guide - Flashcards