Ph.D. Liberty University Microevolution Vs Macroevolution Microevolution Changes in the gene frequency of a population over time. Modification of pre-existing genetic information in population. Factors contributing to Microevolution Genetic drift Mutations Gene flow Natural selection Genetic Drift Random loss of genes or traits in a population through time. Big impact on small populations.
Large populations are more resistant.
Small populations risk extinction Macroevolution Addition of new features within a population when the ancestral stock neither had these features nor the genetic information which codes for it. Puctuationalism Neo-Darwinism Evolutionary change is a slow gradual process evenly distributed over time. Origin of novel adaptive structures is through mutation and natural selection. Punctuationalism Evolutionary change in sudden spurts with long periods of change. Rapid appearance, fully formed, with no apparent ancestors.