Burying beetles occasionally punish young who nag for food by eating those who pester them most, according to Edinburgh University research.It encourages the larvae to plead more honestly according to how hungry they are and not try to outdo their siblings by pestering their mother for food.
It also helps the mother beetle to maintain a degree of control over how she feeds her squabbling offspring.
Cannibalism is also used by parents when food is in short supply.
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.
The Edinburgh University team 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.
Parents’ attention
They found 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 the findings further showed understanding about why animal parents respond to begging.
Like many other mammals and birds, burying beetles seem to favour elder offspring, the scientists said.
It could be because the older offspring are more likely to grow up larger and survive to give them grandchildren in the future.
Dr Clare Andrews, of the University of Edinburgh’s school of biological sciences, said: “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.
“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.”
The study, which is published in Behavioural Ecology, was supported by the Natural Environment Research Council.
