Adaptive radiation is the rapid evolution of multiple species from a common ancestor when introduced to new environmental opportunities. This process often results in a wide variety of forms adapted to different ecological niches.
Speciation: The formation of new and distinct species in the course of evolution.
Ecological Niche: The role and position a species has in its environment, including all interactions with biotic and abiotic factors.
Common Ancestor: An ancestral species from which multiple descendant species have evolved.