[Campbell Biology P.543] Based on the text, in which of the following situations would genet... | Practice Question

Based on the text, in which of the following situations would genetic drift likely have the most significant impact on allele frequencies?

  • A: A very large population of fish consistently adapts to warmer ocean temperatures over hundreds of years.
  • B: A small group of individuals migrates to a new, isolated habitat and starts a new population.
  • C: A massive population of bacteria undergoes rapid reproduction, leading to many new mutations.
  • D: A diverse population of birds experiences a gradual shift in food availability over several decades, favoring certain beak types.

Explanation

The text states that genetic drift is 'especially significant in small populations' and provides the 'founder effect' as a prime example. The scenario in option B a small group establishing a new population perfectly illustrates the founder effect, a type of genetic drift where chance events can lead to a gene pool differing significantly from the source population.