新GRE argument 新G题库中argument第二题2.The following appeared as part of a letter to the editor of a scientific journal."A recent study of eighteen rhesus monkeys provides clues as to the effects of birth order on an individual's levels of s

新GRE argument 新G题库中argument第二题2.The following appeared as part of a letter to the editor of a scientific journal."A recent study of eighteen rhesus monkeys provides clues as to the effects of birth order on an individual's levels of s
新GRE argument
新G题库中argument第二题
2.The following appeared as part of a letter to the editor of a scientific journal.
"A recent study of eighteen rhesus monkeys provides clues as to the effects of birth order on an individual's levels of stimulation.The study showed that in stimulating situations (such as an encounter with an unfamiliar monkey),firstborn infant monkeys produce up to twice as much of the hormone cortisol,which primes the body for increased activity levels,as do their younger siblings.Firstborn humans also produce relatively high levels of cortisol in stimulating situations (such as the return of a parent after an absence).The study also found that during pregnancy,first-time mother monkeys had higher levels of cortisol than did those who had had several offspring."
Write a response in which you discuss one or more alternative explanations that could rival the proposed explanation and explain how your explanation(s) can plausibly account for the facts presented in the argument.
请问如何破题?求各路高手相助~

新GRE argument 新G题库中argument第二题2.The following appeared as part of a letter to the editor of a scientific journal."A recent study of eighteen rhesus monkeys provides clues as to the effects of birth order on an individual's levels of s
结论是：the effects of birth order on an individual's levels of stimulation
1、样本数量太少
2、firstborn infant monkeys produce up to twice as much of the hormone cortisol,which primes the body for increased activity levels,as do their younger siblings.可能是因为第一胎的猴子年龄比较大.
3、人类不一定和猴子一样（这里我也比较迷惑.不知道是事实还是结论）
4、The study also found that during pregnancy,first-time mother monkeys had higher levels of cortisol than did those who had had several offspring.不能证明结论,也不能说明此一次怀孕的母猴与小猴的激素水平的关系
自己的看法.我对这道题也很迷惑啊.

gre好难，不好意思帮不上忙

貌似比老G的argument难不少

个人认为还可以说cortisol并不一定是决定level of stimulation 的关键因素，还有其他因素，如其他激素起决定作用，但作者没有rule out thoes possibilities