Final answer:
Adaptive radiation is the process where a population of one species disperses and adapts to different niches, leading to multiple speciation events. It is exemplified by the Hawaiian honeycreeper, Galapagos finches, and East African cichlid fish.
Step-by-step explanation:
Adaptive Radiation
In some cases, a population of one species disperses throughout an area, and each finds a distinct niche or isolated habitat. Over time, the varied demands of their new lifestyles lead to multiple speciation events originating from a single species.
This is called adaptive radiation because many adaptations evolve from a single point of origin; thus, causing the species to radiate into several new ones. Island archipelagos like the Hawaiian Islands provide an ideal context for adaptive radiation events because water surrounds each island which leads to geographical isolation for many organisms. The Hawaiian honeycreeper illustrates one example of adaptive radiation. From a single species, called the founder species, numerous species have evolved.
Example of adaptive radiation:
The Hawaiian honeycreeper: From a single species, several species of Hawaiian honeycreepers have evolved, each with its own distinctive characteristics.
Another example is the Galapagos finches observed by Darwin. These finches have diversified into several species with different beak sizes and shapes, each adapted to different types of food sources on the islands.
The cichlid fish in East African lakes is another example of adaptive radiation. They have evolved into hundreds of different species, each adapted to exploit a specific ecological niche within the lakes.