An Oxford University study examining the basis of how romantic relationships are formed found that ladies are all about calling and texting their men—bug-a-boo-ing, if you will—until around their mid-thirties, at which point they drop those scrubs in favor of chatting up women half their age.
Not paid escorts (probably); their daughters (probably).
Why? According to evolutionary psychologists, because they want to ensure their daughters have "viable progeny."
In other words: Where are my grandkids?
To cull data for the study, a team of researchers, led by Professor Robin Dunbar, analyzed seven months' worth of mobile phone records, divided by age and gender of phone plan's subscriber, taken from more than 3 million Europeans.
Using both call and text history, researchers identified the most-contacted person (whom they, somewhat presumptuously, designated the "best friend") of each user, then tracked people's relationships with their "best friends" across age group and gender.
It turns out that, between the ages of 20 and 40, men and women behave similarly; they're all about blowing up the phones of the opposite sex. Phone users from this age group were much more likely to have a "best friend" of the gender opposite them, than of their own gender.
This trend was especially true for women — particularly those on the younger end of the spectrum.
For every one woman in her late twenties who had a female "best friend," there were three more in the sample, also in their late twenties, whose best friends were male.
Based on the fact that these opposite gendered "best friends" tended to be of a similar age to the subscribers, researchers concluded, again, perhaps a bit presumptuously, that they must, in fact, have been sexual partners.
"Second best friends" (who, in real life, are probably the actual best friends with whom the texts and calls of study's so-called "best friends" are analyzed) were more likely to be of the same sex as a subscriber.
However, for all their early dude enthusiasm, the data showed that, by around their mid-thirties, women are over it.
Professor Dunbar explains the change:
"What seems to happen is that women push the 'old man' out to become their second best friend, and he gets called much less often and all her attention is focused on her daughters just at the point at which you are likely to see grandchildren arriving."
Here, again, Dunbar is assuming daughters. Because the records only provided researchers with users' ages and sexes, all they could conclude from analyzing them was that, starting in their mid-30s, women suddenly begin calling and texting much more frequently with other women about a generation younger.
These new "best friends" may be nothing more than manic pixie dream girls the women are hooking up with to inject a bit of whimsy into their lives. But daughters makes sense.
Men, on the other hand, are less likely to undergo such a switch at any point. Their most frequently-contacted person tended to remain a female throughout their lives.
You're so desperate, men.
As for why women make this swap, Dunbar offers a super sketchy guess: Maybe, when women hit menopause and are unable to reproduce, they re-evaluate their methods for preserving their line. Instead of focusing on their own sexual partners, as they did in their youth, they put their energy into strengthening their children's (in particular their daughters') odds of producing "viable" offspring.
Or maybe they just miss their daughters because they're going off to college.
Or maybe, 30 years in, they're just tired of talking to their husbands.
[Image via AP]