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Every year parents painstakingly craft holiday presents that are equal in quality and quantity for each child. And still, every year they’re shocked when they’re forced to listen to hours of debate over who got the better gift.
According to the classic 1970s theory of parent-offspring conflict, children know there is limited breast milk at the cradle and limited inheritance at the grave, so each child is programmed to want the lion’s share.
Parents, on the other hand, strives to lavish attention equally among offspring, in order to maximize survival of all genes.
But new research from the University of Manchester found parents instinctively favor the oldest sibling – at least in the Nicrophorus burying beetle, who shares that biparental quality with us humans.
Their study found that the oldest offspring receive the most regurgitated animal flesh from their parents.
Researchers say parents value the older grubs, because they’ve established a better chance of survival…or the older siblings are simply stronger and so grab parental attention.
Either way, the researchers say it proves that familial conflict is still alive and well.
Did we really need reminding?