Which of the following factors would be the most likely to contribute to allopatric speciation?


A. The separated population is large, and genetic drift occurs.
B. Selection pressures in the isolated population are similar to those in the ancestral population.
C. Gene flow between the two populations is extensive.
D. Different mutations begin to distinguish the gene pools of the separated populations.

Verified step by step guidance

1. Understand the concept of allopatric speciation: Allopatric speciation occurs when a population is geographically separated into two or more isolated groups, preventing gene flow between them.
2. Analyze the impact of a large separated population and genetic drift: Genetic drift can lead to significant changes in small populations, but its effect is reduced in larger populations.
3. Evaluate the role of similar selection pressures: If selection pressures are similar in both the isolated and ancestral populations, the genetic makeup of the populations is likely to remain similar, reducing the likelihood of speciation.
4. Consider the effect of extensive gene flow: Extensive gene flow between two populations allows for the exchange of genetic material, which can prevent the populations from diverging significantly and thus inhibit speciation.
5. Assess the impact of different mutations: Different mutations in the gene pools of separated populations can lead to genetic divergence if these mutations lead to different traits that are subject to selection.

Key Concepts

Allopatric Speciation

Allopatric speciation occurs when a population is geographically separated, leading to reproductive isolation. This separation can result from physical barriers like mountains or rivers, preventing gene flow between the groups. Over time, the isolated populations may evolve independently, potentially leading to the emergence of new species.

Genetic Drift

Genetic drift is a mechanism of evolution that involves random changes in allele frequencies within a population. It is particularly significant in small populations, where chance events can lead to the loss or fixation of alleles. This can contribute to divergence between separated populations, enhancing the likelihood of speciation.

Mutation and Gene Pool Divergence

Mutations are changes in the DNA sequence that can introduce new genetic variations into a population. When populations are isolated, different mutations can accumulate in each group, leading to distinct gene pools. This genetic divergence is crucial for speciation, as it can result in populations that are no longer capable of interbreeding.