noun Biology.
- evolutionary change involving the gradual accumulation of mutations leading to new varieties within a species.
- minor evolutionary change observed over a short period of time.
n.
- Evolution resulting from a succession of relatively small genetic variations that often cause the formation of new subspecies.
- Evolutionary change below the level of the species, resulting from relatively small genetic variations. Microevolution produces new strains of microorganisms, for example, or the rise of a new subspecies. The accumulation of many microevolutionary changes results in macroevolution.