What is the X in X-mas?
|adaptive radiation |
The evolutionary diversification of a species or single ancestral lineage into various forms that are each adaptively specialized to a specific environmental niche. Adaptive radiation generally proceeds most rapidly in environments where there are numerous unoccupied niches or where competition for resources is minimal. See Note at adaptation.
evolution of an animal or plant group into a wide variety of types adapted to specialized modes of life. A striking example is the radiation, beginning in the Tertiary period (beginning 66.4 million years ago), of basal mammalian stock into forms adapted to running, leaping, climbing, swimming, and flying.