57.
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?
(A) Major episodes of extinction can result from widespread environmental disturbances that affect numerous different species.
(B) Certain extinction episodes selectively affect organisms with particular sets of characteristics unique to their species.
(C) Some species become extinct because of accumulated gradual changes in their local environments.
(D) In geologically recent times, for which there is no fossil record, human intervention has changed the pattern of extinctions.
(E) Species that are widely dispersed are the least likely to become extinct.
问题的意思不明白呀!!有谁能解答吗?
个人理解:
A:灭绝的特殊事件可能是由于能影响多种物种的广泛的环境变动
B:有些灭绝的特殊事件有选择性的影响有自身特点的生物。
C;一些物种的灭绝是由于其所处环境的渐变的累积效果
D:就没有化石依据的地理近代而言,人类的干预已经改变了灭绝模式。
E:分散的越广泛的种类, 灭绝的可能性越小。
A.主要的灭绝时期是由于能影响多种物种的广泛的环境变动
B。特别灭绝时期是选择性地影响带有某些特征的物种
其他选项意思理解差不多,答案是选 D么?
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