What is microevolution?

1 Answer

It's changes in gene frequency within a population.

Explanation:

Microevolution occurs when there are changes in gene frequency within a population over a short period of time. Microevolution specifically refers to changes within a population, a population being a group of organisms that breed with each other.

Microevolution differs from macroevolution in scale. Macroevolution occurs in a large scale: when we're talking about evolution beyond the species scale, we're talking about macroevolution. The mechanisms of the micro and macroevolution are the same: genetic drift, natural selection, gene flow, and mutations.

http://evolution.berkeley.edu/evolibrary/article/evoscales_01

To learn more, check out this excellent resource from Understanding Evolution.