Population bottlenecks occur when the size of a population is drastically reduced, either through extinction or because of separation.
When this occurs, it is reasonable to assume that the genetic cross-section of the remaining population is not identical to that of the original population. Not all individuals carry every allele present in the original population, so the remaining population will carry only a small portion of the original number of alleles.
This can cause what is known as the 'founder effect'.
A bottleneck can reduce genetic diversity by decreasing the population size, leading to a loss of alleles. This can increase the likelihood of genetic drift and limit the ability of the population to adapt to changing environments. It can also increase the frequency of deleterious alleles due to random fluctuations in the small population.
Apex . . bottleneck
Allele frequencies change randomly each generation. APEX
bottleneck (apex) [correct]
The flood likely caused a genetic bottleneck, reducing the genetic diversity of the ant population. The rapid growth after the flood may have allowed new mutations to become more prominent, leading to changes in allele frequencies. This could result in a genetic drift or selection event.
Genetic drift is the random fluctuation of gene frequencies in a population due to chance events. It can lead to changes in the genetic makeup of a population over time, particularly in smaller populations.
Apex . . bottleneck
Allele frequencies change randomly each generation. APEX
bottleneck (apex) [correct]
The flood likely caused a genetic bottleneck, reducing the genetic diversity of the ant population. The rapid growth after the flood may have allowed new mutations to become more prominent, leading to changes in allele frequencies. This could result in a genetic drift or selection event.
Answer this question… Genetic drift
Genetic drift is the random fluctuation of gene frequencies in a population due to chance events. It can lead to changes in the genetic makeup of a population over time, particularly in smaller populations.
founder effect
evolution within a species. the allele frequencies in a gene pool of a population
No, stable allele frequencies do not prevent microevolution. Microevolution involves changes in allele frequencies within a population over time, even if those frequencies are stable for a period. Evolution can still occur through mechanisms such as genetic drift, selection, and gene flow, even if allele frequencies are temporarily stable.
The type of equilibrium where allele frequencies do not change is called Hardy-Weinberg equilibrium. This equilibrium occurs in an idealized population where certain assumptions are met, such as random mating, no mutation, no migration, no natural selection, and a large population size. In Hardy-Weinberg equilibrium, the genotype frequencies can be predicted using the allele frequencies.
The term you're looking for is "founder effect." It refers to a situation where a small population establishes a new colony which might have different allele frequencies from the original population due to the limited genetic variation carried by the founders.
A bottleneck can lead to a significant reduction in the genetic diversity of a population, causing certain alleles to be lost and others to become more common. This can increase the frequency of rare alleles and result in genetic drift, potentially leading to an increase in genetic diseases or reduced fitness in the population.