Microevolution is the very small evolutionary change specially allele frequencies on the level of species that occurs slowly over period of time. These changes occurs on the level of DNA or genetic level.
These evolution can be caused by the natural selection process or genetic drift over the generation of the species or population over period of the time. It is the study of the evolution that occurred on level of separated gene pool.
The very different characteristics of each type of DNA for each person. Each person has a distinctive set of finger prints saliva and other bodily fluids that is uncommon for anyone else to have the exact same. Hope this helps :)
