Arizona State University (ASU) BIO182 General Biology II Exam 2 Practice

Adaptive radiation is a process that often occurs when a single ancestral species rapidly diversifies into a wide variety of forms to occupy different ecological niches. This phenomenon is commonly associated with allopatric speciation, which occurs when populations are geographically isolated from one another.

In allopatric speciation, barriers such as mountains, rivers, or distance can lead to the separation of populations. When these populations adapt to their unique environments, they can undergo significant evolutionary changes. This process can result in a burst of diversification where numerous new species arise from the original population, each adapted to specific niches. For example, the finches of the Galápagos Islands illustrate adaptive radiation, where one ancestral finch species evolved into multiple species with different beak shapes to exploit various food sources available in the islands.

Understanding this concept highlights the importance of geographic isolation in fostering both speciation and adaptive radiation, linking evolutionary dynamics to ecological opportunities.