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来源：雅诚德英语网
As these experiments show, begging apparently provides a signal of need that parents use to make judgments about which offspring can benefit most from a feeding.
正如这些实验所显示的，乞求显然提供了一种需要的信号，父母可以利用这种信号来判断哪些孩子能从喂食中获益最多。
As these experiments show, begging apparently provides a signal of need that parents use to make judgments about which offspring can benefit most from a feeding.
正如这些实验所显示的，乞求显然提供了一种需要的信号，父母可以利用这种信号来判断哪些孩子能从喂食中获益最多。