OG11-40

amywangwei

(40)    A third theory, proposed by Wynne-Edwards and termed "epideictic," argues that organisms have evolved a "code" in the form of social or epideictic behavior displays, such as winter-roosting aggregations or group vocalizing; such codes

(45) provide organisms with information on population size in a region so that they can, if necessary, exercise reproductive restraint. However, Wynne-Edwards's theory, linking animal social behavior and

population control, has been challenged, with some

(50) justification, by several studies.

以上是跟题目有关的一段，前面是讲其他两种解释数量控制的理论，我的问题是：

40.         According to the Wynne-Edwards theory as it is described in the passage, epideictic behavior displays serve the function of

（A）determining roosting aggregations

（B）locating food

（C）attracting predators

（D）regulating sexual activity

（E）triggering hormonal changes

答案是D，根据原文47行exercise reproductive restraint, 我对D没意见，主要是我不知道E错在哪。OG的解释是Hormonal changes are proposed by the density-dependent theory, not the Wynne-Edwards theory. 照这样说的话，那D选项也是在density-dependent theory中提出来的呀。

而且sexual activity不是由hormonal changes引起的吗？

从原文第三段对这两个词组的提出来看Other regulators include physiological control mechanisms: for example, Christian and Davis have demonstrated how the crowding that results from a rise in numbers may bring about hormonal changes in the pituitary and adrenal glands that in turn may regulate population by lowering sexual activity and inhibiting sexual maturation. 也不能排除E呀？觉得很奇怪，而且没有搜到相关的讨论，请大家指教！

mbamom

以下是引用amywangwei在2007-3-12 23:24:00的发言：

答案是D，根据原文47行exercise reproductive restraint, 我对D没意见，主要是我不知道E错在哪。OG的解释是Hormonal changes are proposed by the density-dependent theory, not the Wynne-Edwards theory. 照这样说的话，那D选项也是在density-dependent theory中提出来的呀。

答案是D，根据原文47行exercise reproductive restraint, 我对D没意见，主要是我不知道E错在哪。OG的解释是Hormonal changes are proposed by the density-dependent theory, not the Wynne-Edwards theory. 照这样说的话，那D选项也是在density-dependent theory中提出来的呀。

而且sexual activity不是由hormonal changes引起的吗？

从原文第三段对这两个词组的提出来看Other regulators include physiological control mechanisms: for example, Christian and Davis have demonstrated how the crowding that results from a rise in numbers may bring about hormonal changes in the pituitary and adrenal glands that in turn may regulate population by lowering sexual activity and inhibiting sexual maturation. 也不能排除E呀？觉得很奇怪，而且没有搜到相关的讨论，请大家指教！

从原文第三段对这两个词组的提出来看Other regulators include physiological control mechanisms: for example, Christian and Davis have demonstrated how the crowding that results from a rise in numbers may bring about hormonal changes in the pituitary and adrenal glands that in turn may regulate population by lowering sexual activity and inhibiting sexual maturation. 也不能排除E呀？觉得很奇怪，而且没有搜到相关的讨论，请大家指教！

不是，虽然density-dependent theory中提到过lowering sexual activity, 但D是从exercise reproductive restraint得来的, WE理论只提到exercise reproductive restraint，并未提到hormone的变化，所以不能得出E结论

另外对于E, 首先hormone changes不一定是sexual activity变化的唯一原因，再有因为没有specified，triggering hormonal changes可以是trigger除pituitary and adrenal glands hormones之外的hormones变化, , 所以不一定引起sexual activity的变化，一句话，答案从原文中来，原文中没提的，不能主观推测

amywangwei

恍然大悟，我终于明白了，之前想了好久，谢谢mbamom