Evolutionary Biology Exam 1 Practice 2026 – FSU
1. Which of the following describes the concept of ‘descent with modification’
as proposed by Darwin?
A. Species remain unchanged over time
B. Individual organisms adapt their traits during their lifetime to survive
C. Species change over time, giving rise to new species and sharing a common ancestor
D. Evolution occurs only through sudden, massive mutations
Answer: C
Rationale: Darwin used the term ‘descent with modification’ to explain that all organisms
are related through an ancestor that lived in the remote past, and that they have
accumulated diverse modifications over time.
2. In the Hardy-Weinberg equation (p^2 + 2pq + q^2 = 1), what does the term
‘2pq’ represent?
A. The frequency of the dominant allele
B. The frequency of the heterozygous genotype
C. The frequency of the homozygous dominant genotype
D. The frequency of the recessive allele
Answer: B
Rationale: In HWE, p and q represent allele frequencies, while p^2, 2pq, and q^2 represent
the frequencies of the homozygous dominant, heterozygous, and homozygous recessive
genotypes, respectively.
,3. Which evolutionary force is the primary source of all new genetic variation?
A. Mutation
B. Genetic Drift
C. Natural Selection
D. Gene Flow
Answer: A
Rationale: Mutation is the ultimate source of genetic variation because it creates new
alleles by changing the DNA sequence.
4. Which of the following is an example of a vestigial structure?
A. The wing of a bird used for flight
B. The camouflage skin of a chameleon
C. The sharp teeth of a lion
D. The pelvic bones in modern whales
Answer: D
Rationale: Vestigial structures are remnants of features that served a function in the
organism’s ancestors but no longer serve a significant purpose; whale pelvic bones are a
classic example.
5. What is the main difference between natural selection and genetic drift?
A. Natural selection is random, while genetic drift is non-random
B. Natural selection always increases genetic diversity
C. Genetic drift only occurs in large populations
D. Natural selection results in adaptation, while genetic drift is due to chance
Answer: D
Rationale: Natural selection is a non-random process that leads to adaptation based on
fitness, whereas genetic drift is a random change in allele frequencies due to sampling
error, especially in small populations.
, 6. A group that includes an ancestral species and all of its descendants is called:
A. Paraphyletic
B. Monophyletic
C. Polyphyletic
D. Analogy
Answer: B
Rationale: A monophyletic group (or clade) consists of an ancestor and every single one of
its descendant species.
7. Which process leads to the formation of analogous structures in different
species?
A. Convergent evolution
B. Common ancestry
C. Genetic drift
D. Stabilizing selection
Answer: A
Rationale: Convergent evolution occurs when unrelated species evolve similar traits
independently because they occupy similar environments or face similar selective
pressures.
8. What does ‘fitness’ specifically refer to in an evolutionary context?
A. An individual’s contribution of genes to the next generation
B. The lifespan of an individual
C. An organism’s physical strength and speed
D. The ability of an organism to survive extreme weather
Answer: A
Rationale: Evolutionary fitness is measured by reproductive success—specifically, how
many offspring an individual leaves relative to others in the population.
1. Which of the following describes the concept of ‘descent with modification’
as proposed by Darwin?
A. Species remain unchanged over time
B. Individual organisms adapt their traits during their lifetime to survive
C. Species change over time, giving rise to new species and sharing a common ancestor
D. Evolution occurs only through sudden, massive mutations
Answer: C
Rationale: Darwin used the term ‘descent with modification’ to explain that all organisms
are related through an ancestor that lived in the remote past, and that they have
accumulated diverse modifications over time.
2. In the Hardy-Weinberg equation (p^2 + 2pq + q^2 = 1), what does the term
‘2pq’ represent?
A. The frequency of the dominant allele
B. The frequency of the heterozygous genotype
C. The frequency of the homozygous dominant genotype
D. The frequency of the recessive allele
Answer: B
Rationale: In HWE, p and q represent allele frequencies, while p^2, 2pq, and q^2 represent
the frequencies of the homozygous dominant, heterozygous, and homozygous recessive
genotypes, respectively.
,3. Which evolutionary force is the primary source of all new genetic variation?
A. Mutation
B. Genetic Drift
C. Natural Selection
D. Gene Flow
Answer: A
Rationale: Mutation is the ultimate source of genetic variation because it creates new
alleles by changing the DNA sequence.
4. Which of the following is an example of a vestigial structure?
A. The wing of a bird used for flight
B. The camouflage skin of a chameleon
C. The sharp teeth of a lion
D. The pelvic bones in modern whales
Answer: D
Rationale: Vestigial structures are remnants of features that served a function in the
organism’s ancestors but no longer serve a significant purpose; whale pelvic bones are a
classic example.
5. What is the main difference between natural selection and genetic drift?
A. Natural selection is random, while genetic drift is non-random
B. Natural selection always increases genetic diversity
C. Genetic drift only occurs in large populations
D. Natural selection results in adaptation, while genetic drift is due to chance
Answer: D
Rationale: Natural selection is a non-random process that leads to adaptation based on
fitness, whereas genetic drift is a random change in allele frequencies due to sampling
error, especially in small populations.
, 6. A group that includes an ancestral species and all of its descendants is called:
A. Paraphyletic
B. Monophyletic
C. Polyphyletic
D. Analogy
Answer: B
Rationale: A monophyletic group (or clade) consists of an ancestor and every single one of
its descendant species.
7. Which process leads to the formation of analogous structures in different
species?
A. Convergent evolution
B. Common ancestry
C. Genetic drift
D. Stabilizing selection
Answer: A
Rationale: Convergent evolution occurs when unrelated species evolve similar traits
independently because they occupy similar environments or face similar selective
pressures.
8. What does ‘fitness’ specifically refer to in an evolutionary context?
A. An individual’s contribution of genes to the next generation
B. The lifespan of an individual
C. An organism’s physical strength and speed
D. The ability of an organism to survive extreme weather
Answer: A
Rationale: Evolutionary fitness is measured by reproductive success—specifically, how
many offspring an individual leaves relative to others in the population.
