Evolutionary Biology Exam 2 Quiz 2026 – FSU
1. Under the Hardy-Weinberg Equilibrium, which of the following is NOT an
assumption?
A. No mutation
B. Random mating
C. Large population size
D. High rate of migration
Answer: D
Rationale: Hardy-Weinberg equilibrium assumes no migration (gene flow), no mutation,
no selection, random mating, and an infinitely large population.
2. If the frequency of a recessive allele (q) is 0.4, what is the frequency of the
homozygous dominant genotype in a population at HWE?
A. 0.36
B. 0.16
C. 0.48
D. 0.60
Answer: A
Rationale: If q = 0.4, then p = 1 - 0.4 = 0.6. The homozygous dominant frequency is p^2,
which is 0.6 * 0.6 = 0.36.
,3. Which evolutionary force is most likely to reduce genetic variation within a
small population over time?
A. Mutation
B. Migration
C. Genetic drift
D. Disruptive selection
Answer: C
Rationale: Genetic drift refers to random changes in allele frequencies and typically leads
to a loss of genetic variation, especially in small populations.
4. A trait that is shared by two or more taxa and their most recent common
ancestor is called a:
A. Homoplasy
B. Synapomorphy
C. Symplesiomorphy
D. Autapomorphy
Answer: B
Rationale: A synapomorphy is a shared derived character used to define monophyletic
groups.
5. Which process results in the formation of a new species due to a physical
geographic barrier?
A. Allopatric speciation
B. Sympatric speciation
C. Polyploidy
D. Parapatric speciation
Answer: A
Rationale: Allopatric speciation occurs when populations become geographically isolated
from one another.
, 6. What is the primary difference between vicariance and dispersal?
A. Dispersal involves a pre-existing barrier
B. Vicariance involves the movement of organisms
C. There is no difference
D. Vicariance involves the appearance of a physical barrier
Answer: D
Rationale: Vicariance occurs when a physical barrier (like a mountain range or river)
splits a population, while dispersal occurs when individuals move to a new area.
7. The ‘Neutral Theory of Molecular Evolution’ suggests that most evolutionary
changes at the molecular level are caused by:
A. Natural selection
B. Sexual selection
C. Environmental adaptation
D. Genetic drift of neutral mutations
Answer: D
Rationale: Neutral theory, proposed by Motoo Kimura, suggests that most genetic
variation is due to drift acting on mutations that do not affect fitness.
8. The biological species concept defines species based on:
A. Reproductive isolation
B. Morphological similarity
C. Ecological niche
D. Phylogenetic lineage
Answer: A
Rationale: The biological species concept defines a species as a group of interbreeding
natural populations that are reproductively isolated from other such groups.
1. Under the Hardy-Weinberg Equilibrium, which of the following is NOT an
assumption?
A. No mutation
B. Random mating
C. Large population size
D. High rate of migration
Answer: D
Rationale: Hardy-Weinberg equilibrium assumes no migration (gene flow), no mutation,
no selection, random mating, and an infinitely large population.
2. If the frequency of a recessive allele (q) is 0.4, what is the frequency of the
homozygous dominant genotype in a population at HWE?
A. 0.36
B. 0.16
C. 0.48
D. 0.60
Answer: A
Rationale: If q = 0.4, then p = 1 - 0.4 = 0.6. The homozygous dominant frequency is p^2,
which is 0.6 * 0.6 = 0.36.
,3. Which evolutionary force is most likely to reduce genetic variation within a
small population over time?
A. Mutation
B. Migration
C. Genetic drift
D. Disruptive selection
Answer: C
Rationale: Genetic drift refers to random changes in allele frequencies and typically leads
to a loss of genetic variation, especially in small populations.
4. A trait that is shared by two or more taxa and their most recent common
ancestor is called a:
A. Homoplasy
B. Synapomorphy
C. Symplesiomorphy
D. Autapomorphy
Answer: B
Rationale: A synapomorphy is a shared derived character used to define monophyletic
groups.
5. Which process results in the formation of a new species due to a physical
geographic barrier?
A. Allopatric speciation
B. Sympatric speciation
C. Polyploidy
D. Parapatric speciation
Answer: A
Rationale: Allopatric speciation occurs when populations become geographically isolated
from one another.
, 6. What is the primary difference between vicariance and dispersal?
A. Dispersal involves a pre-existing barrier
B. Vicariance involves the movement of organisms
C. There is no difference
D. Vicariance involves the appearance of a physical barrier
Answer: D
Rationale: Vicariance occurs when a physical barrier (like a mountain range or river)
splits a population, while dispersal occurs when individuals move to a new area.
7. The ‘Neutral Theory of Molecular Evolution’ suggests that most evolutionary
changes at the molecular level are caused by:
A. Natural selection
B. Sexual selection
C. Environmental adaptation
D. Genetic drift of neutral mutations
Answer: D
Rationale: Neutral theory, proposed by Motoo Kimura, suggests that most genetic
variation is due to drift acting on mutations that do not affect fitness.
8. The biological species concept defines species based on:
A. Reproductive isolation
B. Morphological similarity
C. Ecological niche
D. Phylogenetic lineage
Answer: A
Rationale: The biological species concept defines a species as a group of interbreeding
natural populations that are reproductively isolated from other such groups.
