Does your kid look like your ex?
According to researchers from the University of New South Wales, there’s a type of non-genetic inheritance that means your kids could wind up looking like a past sex partner.
The idea is nothing new — it dates back to ancient Greece. To prove it, Dr. Angela Crean, Dr. Anna Kopps and Professor Russell Bonduriansky looked at male flies and then studied their offspring. They found that the young tended to be similar in size to a mother’s first mate instead of her second (the biological father).
“Our discovery complicates our entire view of how variation is transmitted across generations, but also opens up exciting new possibilities and avenues of research. Just as we think we have things figured out, nature throws us a curve ball and shows us how much we still have to learn,” said Crean, the lead author of the study, which was published in Ecology Letters.
Curve ball is right, especially if your first mate was like, eons ago.
The researchers say that the resemblance is because immature eggs absorb molecules in the seminal fluid of your first mate. That, then, impacts the development of the second male’s offspring.
“Even though the second male sired the offspring, offspring size was determined by what the mother’s previous mating partner ate as a maggot,” Crean said.
Assuming this research could be true for humans, your ex could kind of come back to “haunt” you. Or his precious face could be a sweet reminder of your first time. Or, maybe this is the perfect excuse to hunt down Leonardo DiCaprio to get in on his gene pool?
“We know that features that run in families are not just influenced by the genes that are passed down from parents to their children. Various non-genetic inheritance mechanisms make it possible for maternal or paternal environmental factors to influence characteristics of a child,” Crean said, adding that it’s not clear how their findings relate to other species including humans.
In the meantime, we’re keeping tabs on you Leo.