Which of the Following Events Would Be Least Likely to Trigger

Question

Which of the following events would be least likely to trigger an adaptive radiation?
A)the evolution of new innovations, such as jaws, teeth, seeds
B)colonization of new habitats
C)presence of few competitors and/or predators
D)colonization of uninhabited islands
E)small habitats with few vacant ecological niches

Accepted Answer

Adaptive radiation occurs when a group of organisms diversifies to fill different ecological niches, but if there are few vacant ecological niches (as in small habitats), there is limited opportunity for diversification. Thus, colonization of small habitats with few vacant ecological niches would be least likely to trigger an adaptive radiation.