Adaptive Radiation (DP IB Biology)

Adaptive Radiation

Adaptive radiation

• Natural selection can result in the rapid evolution of multiple species from a common ancestor

  • This is known as adaptive radiation

• These new species are likely to have some similar features due to their shared ancestry

• The differences that arise between the new species often enable them to live together in one habitat because they are able to fill different ecological niches

  • An organism's ecological niche is its role within its ecosystem, e.g. the food that it eats, the environmental conditions that it requires, the predators that it provides food for, etc.

• Examples of groups of species that show adaptive radiation include

  • Darwin's finches; many species of small birds observed by Darwin in the Galapagos islands

  • Hawaiian honeycreepers; a group of more than 50 bird species found in the Hawaiian archipelago

Adaptive radiation example diagram

Adaptive radiation is thought to have given rise to the many species of Hawaiian honeycreeper. Some of these species are able to co-exist on the same island due to filling different niches.