本题目来源于试卷: Unity and Diversity A.8 Evolution and Speciation,类别为 IB生物学
[单选题]
What can result in speciation among organisms livi 8cxo 8.3z05cg jwdx9ofdllq9 ng in 9x87fx f2q crejzbv8,the same location?
A. Behavioural isolation
B. Geographic isolation
C. Stabilising selection
D. Directional selection
参考答案: A
本题详细解析:
Speciation comes about through reproductive isolation which can result frod ) i eoo5qxn0 -jlr;j6p0ny,gm behavioural isolation, in which a population of a species can no longer interbreed with other populations of the species. For example, some segments of a population may respond to a particular mating call or mating behaviour not expressed by another segment of the population.Geographic isolation (Choice B) occurs when populations are prevented from interbreeding because they are in different physical locations. In this question they are in the same location, therefore tog n-jq)00onjr dyel6;pi, 5xhis is incorrect. Stabilising selection (Choice C) is a type of natural selection that promotes an intermediate phenotype, so extremes are reduced, and it does not result in speciation. Directional selection (Choice D) is a type of natural selection that promotes an extreme phenotype, but the selection is in one direction so it does not divide the population and so does not lead to speciation. Only if selection occurs in both directions (divergent selection) does it tend to lead to speciation.
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