This process has been a barrier to same-sex parenthood, since the methylation prevents an embryo with same-sex parents from developing normally.
"The reason you can't ordinarily do that…I would guess isn't as related to aging as to the way males and females have different interests," said Harrison.
Since males are not guaranteed to be the partner of the female, they would have more interest in having a child grow quicker to ensure immediate survival, for example, while a female -- who often needs to raise the children -- would have an interest in smaller children who are easier to raise. That idea is known as the parental conflict hypothesis.
"There's some tendency for the male imprinting pattern to increase growth rates," said Harrison.
In their paper, the researchers noted that smaller size -- a feature of female interests -- seemed to correspond with longer life.
But Harrison noted that "generally, the smaller mice live longer. However, smaller mice don't always live longer, it's a generalization."
But longer lives may not always be an evolutionary advantage.
"Post-reproductive lifespan is going to be irrelevant, primarily in the context of survival of one's offspring," said Keith Latham, a professor of biochemistry at the Fels Institute for Cancer Research and Molecular Biology at Temple University.
Aa Machiavellian as it may sound, longer life, he said, has little evolutionary benefit once an animal has had children, but can be harmful to the population of animals, since they still need things like food.
"Shorter lifespan, in a population, would tend to eliminate post-reproductive individuals and [expand] the environmental resources available to the population," said Latham.