Blog #3: Explain what microevolution is? What are the three ways that variation occurs?

                                                             

      

                        Microevolution is a change in gene frequency within a population.  This change is because of four different processes: mutation, artificial and natural selection, gene flow and genetic drift.  Evolution at this scale can be observed over short periods of time — for example, between one generation and the next, the frequency of a gene for pesticide resistance in a population of crop pests increases. Such a change might come about because natural selection favored the gene, because the population received new immigrants carrying the gene, because some nonresistant genes mutated to the resistant version, or because of random genetic drift from one generation to the next.  Microevolution is reductionist meaning an approach to understanding the nature of complex things by reducing them to the interactions of their parts.  


                    Variation can occur three different ways.  Variation can occur when all the organisms produce more offspring then one can survive to adulthood and reproduce, many of these offspring will die without reproduction.  Another way that variation can occur is when the variation is heritable, if it's in the parents it's passed on to the offspring.  A third way that variation can occur is by an absence of mutation.