Question

Describe three or more genetic mechanisms that may lead to the rapid evolution of a new species. Which of these genetic mechanisms are influenced by natural selection, and which are not?

Short answer

Genetic mechanisms that lead to rapid evolution of new species include mutation, gene flow, and genetic drift. Both mutation and gene flow can sometimes be influenced by natural selection, especially if they confer a survival advantage. However, genetic drift is a random process, not directly influenced by natural selection.

Step-by-step solution

Identify Genetic Mechanisms

Three widely accepted genetic mechanisms that lead to the rapid evolution of a new species include mutation, gene flow, and genetic drift. All these mechanisms cause changes in a species' DNA and therefore changes in species over time.

Determine Influence of Natural Selection

Now, it is crucial to discern the genetic mechanisms influenced by natural selection. Natural selection is a process where organisms better adapted to their environment survive and reproduce more than those less adapted. Thus, mutations can sometimes be influenced by natural selection, especially if they confer a survival advantage. Gene flow can also be subject to natural selection if certain traits brought in or out by immigration or emigration are selected for or against.

Determine Mechanisms Unaffected by Natural Selection

Genetic drift, on the other hand, is not influenced by natural selection. It is a random process that involves changes in gene frequencies over time due to random sampling errors. It can lead to the loss of genetic variation within populations, and the fixation or loss of alleles, irrespective of the survival or reproductive advantage they may or may not confer.