题目选项分析

Extinction is a process that can depend on a variety of ecological, geographical, and physiological variables.These variables affect different species of organisms in different ways, and should, therefore, yield a random pattern of extinctions.However, the fossil record shows that extinction occurs in a surprisingly definite pattern, with many species vanishing at the same time.

Which of the following, if true, forms the best basis for at least a partial explanation of the patterned extinctions revealed by the fossil record?

【选项】Some species become extinct because of accumulated gradual changes in their local environments.