Which of the following factors would not contribute to allopatric speciation? a. The separated population is small, and genetic drift occurs. b. The isolated population is exposed to different selection pressures than the ancestral population. c. Different mutations begin to distinguish the gene pools of the separated populations. d. Gene flow between the two populations is extensive.

Verified step by step guidance

1. Step 1: Understand the concept of allopatric speciation. Allopatric speciation is a mode of speciation that occurs when biological populations of the same species become isolated from each other to an extent that prevents or interferes with genetic interchange.
2. Step 2: Analyze each option in relation to the concept of allopatric speciation. The key to allopatric speciation is the lack of gene flow or genetic interchange between the separated populations.
3. Step 3: Option a, b, and c all contribute to allopatric speciation. A small separated population can lead to genetic drift, different selection pressures can lead to different evolutionary paths, and different mutations can distinguish the gene pools of the separated populations.
4. Step 4: Consider option d. Extensive gene flow between the two populations would actually prevent speciation, as it would allow the two populations to interbreed and maintain similar gene pools.
5. Step 5: Conclude that the factor that would not contribute to allopatric speciation is option d: Gene flow between the two populations is extensive.

Key Concepts

Allopatric Speciation

Allopatric speciation occurs when a population is geographically separated, leading to reproductive isolation. Over time, the isolated populations may evolve independently due to different environmental pressures, genetic drift, and mutations, resulting in the emergence of new species. This process highlights the importance of physical barriers in the diversification of life.

Genetic Drift

Genetic drift is a mechanism of evolution that refers to random changes in allele frequencies within a population, particularly in small populations. It can lead to significant changes over generations, potentially resulting in the loss of genetic variation and the fixation of certain traits. This phenomenon is crucial in allopatric speciation as it can enhance divergence between isolated populations.

Gene Flow

Gene flow is the transfer of genetic material between populations through migration and interbreeding. Extensive gene flow can counteract the effects of speciation by homogenizing genetic differences between populations, making it less likely for them to evolve into distinct species. In the context of allopatric speciation, high levels of gene flow would inhibit the divergence necessary for speciation to occur.