Questions: If a population of otters is reduced dramatically in size, will lead to the loss of substantial genetic variation, even if the population size recovers after a few generations. gene flow a bottleneck artificial selection sexual selection natural selection

The answer is the second one (a bottleneck): a bottleneck will lead to the loss of substantial genetic variation, even if the population size recovers after a few generations.

Explanation for each option:

1. Gene flow: This refers to the transfer of genetic variation from one population to another. It generally increases genetic variation within a population, not decreases it.
2. A bottleneck: This occurs when a population's size is significantly reduced for at least one generation. Because the population is so small, genetic variation is lost due to random sampling of alleles. Even if the population size recovers, the genetic diversity that was lost during the bottleneck cannot be regained.
3. Artificial selection: This is the process by which humans breed plants and animals for particular genetic traits. While it can reduce genetic variation, it is not typically associated with a dramatic reduction in population size.
4. Sexual selection: This is a mode of natural selection where certain traits increase an individual's chances of mating. It can lead to changes in allele frequencies but does not necessarily reduce genetic variation dramatically.
5. Natural selection: This is the process where organisms better adapted to their environment tend to survive and produce more offspring. It can reduce genetic variation if certain alleles confer a significant survival advantage, but it is not typically associated with a dramatic reduction in population size.

Summary: A bottleneck will lead to the loss of substantial genetic variation, even if the population size recovers after a few generations.