Question

这句话怎么分析呀~Therefore,a begging nestling that secures food at t

Answer 1

Therefore, a begging nestling(主语) that secures food at the expense of its siblings （对主语加的定语从句）might actually leave behind （谓语）fewer copies of its genes overall （宾语）than it might otherwise（than 引导的比较状语从句）

定语从句分析

that（主语） secures （谓语）food （宾语）at the expense of its siblings （状语）,因为先行词在从句中充当主语作用,因而关系代词用that

比较状语从句用than来引导it might otherwise,这是一个省略句,看出来谓语只出现了情态动词,后面的动词原形还有宾语全都省略了