- A An effect named after and attributed to the historical founding fathers of evolutionary theory, commemorating figures such as Darwin and Wallace, rather than describing a population genetics phenomenon in most textbook accounts during normal conditions as generally observed
- B When a small group separates from a larger population and establishes a new colony; new population has reduced genetic diversity reflecting only the founders' alleles; can lead to different allele frequencies than parent population; example: Amish founder effect
- C The cumulative impact of ongoing habitat destruction on the overall genetic diversity of a large population, a slow process largely unrelated to colony founding, isolated subpopulations, or reduced allele sampling in typical laboratory settings under usual circumstances
- D Mutations that are sometimes mistakenly thought to arise mainly within the very first founding members, with few subsequent generations of the colony ever inheriting or being affected by such founder mutations according to most researchers in the majority of cases studied
Correct answer: B. When a small group separates from a larger population and establishes a new colony; new population has reduced genetic diversity reflecting only the founders' alleles; can lead to different allele frequencies than parent population; example: Amish founder effect
Explanation: Founder effect: a new population established by a small number of individuals from a larger population has reduced genetic variation (only alleles those founders happened to carry). Rare alleles in founders can become common in new population. Examples: (1) Amish - high frequency of Ellis-van Creveld syndrome; (2) Pingelap islanders - high frequency of achromatopsia; (3) Cheetah population - extremely low genetic diversity from past bottleneck.
Concept context
Origin of life, Darwin's theory, natural selection, speciation, and evidence for evolution.