科学美国人60秒 SSS 2013-09-04（在线收听）

 A baby's cries for food might drive tired parent aggravation,but some species take more drastic measures like the burying beetle,the [xxxxx] which punish it's pesky children by eating them,researches  want to get to the bottom of a age-old  question in evolutionary biology,the origin of begging, Natural selection favors of greedy well-fed child,but it also favors parents xxxx food evenly to the young and save some for themselves.So how do you result that parent child conflict,burying beetles do so by putting the ultimate price on pleading:death.Begging larvae were 13 times more likely than layback larvae to be eating by mom which may discourage from asking for more than their fair sure in the grub. That finding appears in the journal behavior ecology,humans have different standers than beetles do of course,For us pestering your parents may be a good thing.One study suggest crying  to sign a good health which may lower baby's chance that being neglected or abused, Than again, after the first few years,you probably better off not being a cry baby.