Adult women and men are often jealous about completely different threats to their relationship; and these differences seem to establish themselves far sooner than people need them.
These are the findings of a study – “Investigating the emergence of sex differences in jealousy responses in a large community sample from an evolutionary perspective” by Per Helge H. Larsen, Mons Bendixen, Trond Viggo Grøntvedt, Andrea M. Kessler and Leif Edward Ottesen Kennair – that appeared in Scientific Reports.
Here’s the thing: Jealousy associated with a partner’s infidelity has clearly been an evolutionary advantage.
“Jealousy is activated when a relationship we care about is threatened. The function is probably to minimize threats to this relationship. These threats have historically been somewhat different for men and women,” said Larsen.
Evolutionary psychology can help explain the gender differences having to do with this jealousy. The differences in sexual jealousy between the sexes, simply put, revolve around the possibilities for their own children.
Previous research established that men more often react more negatively when their partner has had sex with others than if she falls in love or spends time with someone without having sex. It’s easy to explain this – i.e. if the woman is sexually unfaithful, it ultimately means that her partner might need to use his own resources to raise another man’s children.
Women, on the other hand, are always sure that the child is theirs. They tend to react more negatively to their partner having feelings for another woman than that he’s had sex with her. This response can also be explained – e.g. historically, she could suffer a loss of resources and status for herself and their child if he left her for someone else.
“Jealousy is potentially a costly reaction, perhaps especially for the man before he is physically strong enough to defend himself and his partner against rivals, and before he would normally have had the opportunity to have a steady partner through marriage,” said Kennair.
The researchers, nonetheless, noted that jealousy exists even before one is at an age to take care of his/her partner.
For this study, 1,266 pupils aged 16 to 19 years in upper secondary school were involved. The researchers found that:
- The gender differences in jealousy responses arise even earlier than age 16.
- Distinguishing between sexual jealousy and other types of jealousy can quickly become meaningless for the very youngest among us.
In one way or another, “the benefits of this early, gender-specific sexual jealousy must have outweighed its dangers,” said Kennair. “It could be that the early development of sexual jealousy is simply preparing us for adulthood, and that it has no other function at a younger age.”
But Kennair emphasized that jealousy is a dangerous feeling. Young men could put themselves in danger by experiencing this feeling before it was appropriate and they were physically strong enough to defend the relationship.