Which term describes the movement of alleles into and/or out of a population?
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How do populations respond to all these forces? As relative allele frequencies change, relative genotype frequencies may also change. Each genotype in the population usually has a different fitness for that particular environment. In other words, some genotypes will be favored, and individuals with those genotypes will continue to reproduce. Other genotypes will not be favored: individuals with those genotypes will be less likely to reproduce. What type of genotype would be unfavorable? Unfavorable genotypes take many forms, such as increased risk of predation, decreased access to mates, or decreased access to resources that maintain health. Overall, the forces that cause relative allele frequencies to change at the population level can also influence the selection forces that shape them over successive generations. Show
For example, if moths with genotype aa migrate into a population composed of AA and Aa individuals, they will increase the relative allele frequency of a. However, if the aa genotype has a clear disadvantage to survival (e.g. vulnerability to predation), eventually the changes brought about by the initial migration will be reversed. Here is an example of how a specific genotype is less favorable than another genotype: \( \newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \) \( \newcommand{\vecd}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash {#1}}} \)\(\newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\) \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\) \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\) \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\) \( \newcommand{\Span}{\mathrm{span}}\) \(\newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\) \( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\) \( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\) \( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\) \( \newcommand{\Span}{\mathrm{span}}\)\(\newcommand{\AA}{\unicode[.8,0]{x212B}}\) A population’s genetic variation changes as individuals migrate into or out of a population and when mutations introduce new alleles. Learning Objectives
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Gene FlowAn important evolutionary force is gene flow: the flow of alleles in and out of a population due to the migration of individuals or gametes. While some populations are fairly stable, others experience more movement and fluctuation. Many plants, for example, send their pollen by wind, insects, or birds to pollinate other populations of the same species some distance away. Even a population that may initially appear to be stable, such as a pride of lions, can receive new genetic variation as developing males leave their mothers to form new prides with genetically-unrelated females. This variable flow of individuals in and out of the group not only changes the gene structure of the population, but can also introduce new genetic variation to populations in different geological locations and habitats.  Maintained gene flow between two populations can also lead to a combination of the two gene pools, reducing the genetic variation between the two groups. Gene flow strongly acts against speciation, by recombining the gene pools of the groups, and thus, repairing the developing differences in genetic variation that would have led to full speciation and creation of daughter species. For example, if a species of grass grows on both sides of a highway, pollen is likely to be transported from one side to the other and vice versa. If this pollen is able to fertilize the plant where it ends up and produce viable offspring, then the alleles in the pollen have effectively linked the population on one side of the highway with the other. MutationMutations are changes to an organism’s DNA and are an important driver of diversity in populations. Species evolve because of the accumulation of mutations that occur over time. The appearance of new mutations is the most common way to introduce novel genotypic and phenotypic variance. Some mutations are unfavorable or harmful and are quickly eliminated from the population by natural selection. Others are beneficial and will spread through the population. Whether or not a mutation is beneficial or harmful is determined by whether it helps an organism survive to sexual maturity and reproduce. Some mutations have no effect on an organism and can linger, unaffected by natural selection, in the genome while others can have a dramatic effect on a gene and the resulting phenotype. This page titled 19.2C: Gene Flow and Mutation is shared under a CC BY-SA 4.0 license and was authored, remixed, and/or curated by Boundless. What is the term for the movement of alleles into or out of a population through immigration and emigration?Gene flow is the movement of genes into or out of a population. Such movement may be due to migration of individual organisms that reproduce in their new populations, or to the movement of gametes (e.g., as a consequence of pollen transfer among plants).
Is the produce of the migration of alleles into and out of a population?An important evolutionary force is gene flow: the flow of alleles in and out of a population due to the migration of individuals or gametes.
Which refers to the movement of genes into or out of a population due to either the movement of individual organisms or their gametes?Gene flow.
Gene flow involves the movement of genes into or out of a population, due to either the movement of individual organisms or their gametes (eggs and sperm, e.g., through pollen dispersal by a plant).
Which of the following describes when individuals move in or out of a population?Migration. Migration is the movement of organisms from one location to another. Although it can occur in cyclical patterns (as it does in birds), migration when used in a population genetics context often refers to the movement of individuals into or out of a defined population.
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