London: Scientists have found that burying beetles dish out an unusual punishment to young that nag for food - they eat those who pester their parents the most!
This severe punishment encourages the remaining beetle larvae to plead more honestly according to how hungry they are - and not try to outdo their siblings by pestering their mother for more food, the researchers from University of Edinburgh said.
The reprimand also let the mother beetle maintain a degree of control over how she feeds her squabbling offspring.
Cannibalism is also occasionally used by parents when food is in short supply to reduce the number of mouths they have to feed, researchers found.
Burying beetle larvae pester for food by touching the parent`s mouths with their legs. Parent beetles then feed their young by regurgitating pre-digested flesh.
Researchers gave mothers large foster families to find out if they were more likely to cannibalise offspring that begged most for food.
Researchers also examined whether mothers could control how food was shared between older and younger offspring.
They found that when mother beetles were able to control which larvae to feed - even if younger and older larvae were pestering for food - they chose to feed older offspring.
Researchers said that the findings further understanding about why animal parents respond to begging. Like many other mammals and birds, burying beetles seem to favour elder offspring, they added.
This could be because the older offspring are more likely to grow up larger and survive to give them grandchildren in the future.
"We already knew that larvae beg more if they have been deprived of food but we had not known whether this is because they are informing their parents how hungry they are or whether they are simply squabbling with each other to get their parents` attention," said Dr Clare Andrews of the University of Edinburgh`s School of Biological Sciences.
"Our study shows that if you`re a baby beetle it doesn`t pay to pester your mother for food unless you`re really hungry. Communication is crucial in helping to mediate conflicts of interests between parents and offspring," Andrews said.
The study was published in journal Behavioural Ecology.