Question 1

Which of the following best describes Darwin's four postulates of natural selection?

Accepted Answer

Variation exists among individuals, traits are heritable, more offspring are produced than can survive, and survival is non-random.

Question 2

A population of beetles has two alleles for color: G (green) and g (brown). If the frequency of G is $$p = 0.7$$ and g is $$q = 0.3$$, what is the expected frequency of heterozygotes under Hardy-Weinberg equilibrium?

Accepted Answer

$$2pq = 0.42$$

Question 3

Which scenario best illustrates genetic drift?

Accepted Answer

A population of rabbits is reduced to a few individuals after a flood, and the surviving population has different allele frequencies than the original.

Question 4

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

Accepted Answer

Natural selection is acting on the population.

Question 5

A scientist observes that a population of finches has developed larger beaks over several generations due to a drought that made only large seeds available. Which evolutionary process is most likely responsible for this change?

Accepted Answer

Natural selection

Question 6

Which of the following best describes allopatric speciation?

Accepted Answer

Speciation occurs when populations are separated by a physical barrier.

Question 7

In a population, the frequency of allele A is $$p = 0.4$$ and allele a is $$q = 0.6. $$What is the expected frequency of homozygous recessive individuals ($$aa) $$under Hardy-Weinberg equilibrium?

Accepted Answer

$$q^2 = 0.36$

Question 8

Which process increases genetic variation within a population?

Accepted Answer

Mutation

Question 9

Which of the following is an example of vicariance?

Accepted Answer

A river changes course and splits a population of frogs into two isolated groups.

Question 10

Which type of selection favors individuals with intermediate phenotypes and reduces variation?

Accepted Answer

Stabilizing selection

Question 11

A population of fish in a lake is found to have a higher frequency of a rare allele after a group of fish from a nearby river migrates into the lake. Which evolutionary process is illustrated?

Accepted Answer

Gene flow

Question 12

Which of the following is a biological species concept criterion?

Accepted Answer

Species are defined by their ability to interbreed and produce viable, fertile offspring.

Question 13

Which of the following is true about monophyletic groups in phylogenetic trees?

Accepted Answer

They include all descendants of a common ancestor.

Question 14

A scientist is comparing two phylogenetic trees for a group of mammals. Which criterion should be used to determine which tree is best?

Accepted Answer

The tree that requires the fewest evolutionary changes (parsimony).

Question 15

Which of the following is an example of sympatric speciation?

Accepted Answer

A population of insects splits into two species due to a mutation causing reproductive isolation, even though they live in the same area.

Question 16

Which of the following best describes disruptive selection?

Accepted Answer

Selection favors individuals at both extremes of a trait distribution.

Question 17

A population of plants undergoes polyploidy, resulting in instant reproductive isolation from the parent population. What type of speciation is this?

Accepted Answer

Sympatric speciation

Question 18

Which of the following is NOT a mechanism of non-random mating?

Accepted Answer

Random mating

Question 19

Which of the following is a morphological species concept criterion?

Accepted Answer

Species are defined by measurable physical traits.

Question 20

Which evolutionary process is most likely to decrease genetic variation in a small population over time?

Accepted Answer

Genetic drift

Evolution, Population Genetics, and Phylogeny: Study Guide

Study Guide - Practice Questions

Study Guide - Flashcards