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'.
Apex . . bottleneck
Allele frequencies change randomly each generation. APEX
bottleneck (apex) [correct]
The bottleneck effect and founder effect are both examples of genetic drift in population genetics. The bottleneck effect occurs when a large population is drastically reduced in size, leading to a loss of genetic diversity. The founder effect happens when a small group of individuals establishes a new population, leading to a limited gene pool. Both effects can result in changes in allele frequencies and genetic variation within a population.
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.
Apex . . bottleneck
Allele frequencies change randomly each generation. APEX
bottleneck (apex) [correct]
The bottleneck effect and founder effect are both examples of genetic drift in population genetics. The bottleneck effect occurs when a large population is drastically reduced in size, leading to a loss of genetic diversity. The founder effect happens when a small group of individuals establishes a new population, leading to a limited gene pool. Both effects can result in changes in allele frequencies and genetic variation within a population.
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 change in allele frequencies due to random chance events. Two types are the Founder effect and the Bottleneck effect. The founder effect is when a subset of a population goes to a new are where there are no other of that same species. The bottleneck effect is when a large population is reduced to a small population. Genetic drift decreases variation in a population and has a greater effect on a smaller population than a larger one.
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.