Biology Mechanisms of Natural Selection Flashcards

Sexual selection differs from natural selection primarily because it:

Answer: Involves competition for mates rather than survival

Sexual selection specifically involves differential reproductive success based on mate competition or mate choice, not merely survival.

The concept of 'fitness' in evolutionary biology specifically refers to:

Answer: Reproductive success relative to other individuals

Evolutionary fitness is defined as an individual's ability to survive and reproduce relative to others in the population.

Which scenario illustrates the founder effect?

Answer: A few birds colonize a distant island and establish a new population

The founder effect occurs when a small group establishes a new population, carrying only a subset of the original genetic variation.

Heterozygote advantage (overdominance) maintains two alleles in a population because:

Answer: Heterozygotes have higher fitness than either homozygote

When heterozygotes are more fit than either homozygote, both alleles are preserved through balancing selection.

Which of the following would INCREASE the rate of evolution by natural selection?

Answer: High heritability of traits

High heritability means traits are strongly passed from parent to offspring, making natural selection more effective at changing allele frequencies.

Random genetic drift has the greatest effect on allele frequencies in:

Answer: Small, isolated populations

Genetic drift is a random process whose effects are amplified in small populations where chance events significantly alter allele frequencies.

Mimicry in which a harmless species resembles a dangerous one to deter predators is called:

Answer: Batesian mimicry

Batesian mimicry occurs when a palatable or harmless species evolves to resemble an unpalatable or dangerous model species.