Q25-8TYU Describe how gene flow, genetic ... [FREE SOLUTION]

Chapter 25: Q25-8TYU (page 549)

Describe how gene flow, genetic drift, and natural selection all can influence macroevolution.

Short Answer

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Gene flow causes an increase in the allele frequency and introduces new allele combinations. In this manner, gene flow increases the genetic variability of a population and helps in macroevolution.

Genetic drift also imparts huge changes in the allele frequency and enhances macroevolution. Natural selection is the most important factor that promotes the selection of organisms with better traits.

Step by step solution

Macroevolution

The term macroevolution is used to refer to a broader class of the population. Macroevolution studies the tree of life just above the species level. Generally, macroevolution occurs due to genetic drift, gene flow, and natural selection.

Gene flow, genetic drift, and natural selection affecting macroevolution

The genetic alteration brings about macroevolution in a population. Several microevolutions can collectively cause macroevolution. The two main events that allow macroevolution are genetic drift and gene flow.

Genetic drift enables random changes in gene frequency over generations.Due to such events, sometimes a new population might arise from a larger population.

Gene flow enhances genetic recombination into a population and allows a new combination of traits. On the other hand, natural selection works by selecting the beneficial traits among a population, over time, bringing macroevolution.

Macroevolution and its significance

All the traits mentioned above allow macroevolution. The gene flow and genetic drift increase genetic variability by altering the allele frequency.

The changes in allele frequency are important for the sustainability and growth of a population in response to the changing environment and competition. Therefore, macroevolution occurs over prolonged generations for the benefit of a species.