Two populations of deer, one of them large and living in a mainland forest and the other small and inhabiting a forest on an island, regularly exchange members that migrate across a land bridge that connects the island to the mainland. In which population do you expect to see the greatest allele frequency change? Why?

Verified step by step guidance

1. Understand the concept of allele frequency: Allele frequency refers to how common a particular allele is in a population. It is influenced by factors such as genetic drift, migration, mutation, and natural selection.
2. Recognize the role of population size: Genetic drift, which is the random change in allele frequencies, has a stronger effect in smaller populations because random events can disproportionately impact the gene pool.
3. Consider the impact of migration: Migration introduces new alleles into a population or removes alleles from it, altering allele frequencies. The smaller population is more likely to experience significant changes due to the influx or outflow of alleles.
4. Analyze the scenario: The island population is smaller, so genetic drift and migration will have a greater impact on its allele frequencies compared to the larger mainland population. The larger population is more stable and less susceptible to random changes.
5. Conclude the reasoning: The greatest allele frequency change is expected in the smaller island population because it is more affected by genetic drift and migration due to its size and limited genetic diversity.

Key Concepts

Genetic Drift

Genetic drift refers to the random fluctuations in allele frequencies within a population, particularly in small populations. In smaller populations, such as the island deer, random events can have a more significant impact on allele frequencies, leading to greater changes over time compared to larger populations.

Gene Flow

Gene flow is the transfer of genetic material between populations through migration. In this scenario, the exchange of deer between the mainland and island populations can introduce new alleles to each population, potentially altering allele frequencies. The extent of gene flow can influence genetic diversity and adaptation in both populations.

Population Size and Allele Frequency Change

The size of a population plays a crucial role in how allele frequencies change over time. Larger populations tend to maintain stable allele frequencies due to the buffering effect of a greater number of individuals, while smaller populations are more susceptible to rapid changes in allele frequencies due to genetic drift and the effects of inbreeding.