Hi y'all - that settles it - I'm going to sweat more. Would you care to sniff my armpit?
On Dec 5, 10:26 am, CrossBow <[EMAIL PROTECTED]> wrote: > That "Smell Factor" again... > > Major Histocompatibility Complex Alleles, Sexual Responsivity, and > Unfaithfulness in Romantic Couples > > Copyright Copyright (c) 2006 Association for Psychological Science > ABSTRACT > > *ABSTRACT—*Preferences for mates that possess genes dissimilar to one's own > at the major histocompatibility complex (MHC), a polymorphic group of loci > associated with the immune system, have been found in mice, birds, fish, and > humans. These preferences may help individuals choose genetically compatible > mates and may adaptively function to prevent inbreeding or to increase > heterozygosity and thereby immunocompetence of offspring. MHC-dissimilar > mate preferences may influence the psychology of sexual attraction. We > investigated whether MHC similarity among romantically involved couples (*N*= > 48) predicted aspects of their sexual relationship. All women in our sample > normally ovulated, and alleles at three MHC loci were typed for each person. > As the proportion of MHC alleles couples shared increased, women's sexual > responsivity to their partners decreased, their number of extrapair sexual > partners increased, and their attraction to men other than their primary > partners increased, particularly during the fertile phase of their cycles. > and... > Birth Control Pills Affect Women's Taste in Men How synthetic hormones > change desire in women--and their choice in a mate By Melinda Wenner > > This year 2.25 million Americans will get married—and a million will get > divorced. Could birth control be to blame for some of these breakups? Recent > research suggests that the contraceptive pill—which prevents women from > ovulating by fooling their body into believing it is pregnant—could affect > which types of men women desire. Going on or off the pill during a > relationship, therefore, may tempt a woman away from her man. > > It's all about scent. Hidden in a man's smell are clues about his major > histocompatibility complex (MHC) genes, which play an important role in > immune system surveillance. Studies suggest that females prefer the scent of > males whose MHC genes differ from their own, a preference that has probably > evolved because it helps offspring survive: couples with different MHC genes > are less likely to be related to each other than couples with similar genes > are, and their children are born with more varied MHC profiles and thus more > robust immune systems. > > A study published in August in the *Proceedings of the Royal Society B*, > however, suggests that women on the pill undergo a shift in preference > toward men who share similar MHC genes. The female subjects were more likely > to rate these genetically similar men's scents (via a T-shirt the men had > worn for two nights) as pleasant and desirable after they went on the pill > as compared with before. Although no one knows why the pill affects > attraction, some scientists believe that pregnancy—or in this case, the > hormonal changes that mimic pregnancy—draws women toward nurturing > relatives. > > Women who start or stop taking the pill, then, may be in for some > relationship problems. A study published last year in *Psychological Science > * found that women paired with MHC-similar men are less sexually satisfied > and more likely to cheat on their partners than women paired with > MHC-dissimilar men. So a woman on the pill, for example, might be more > likely to start dating a MHC-similar man, but he could ultimately leave her > less sexually satisfied. Then if she goes off the pill during the > relationship, the accompanying hormonal changes will draw her even more > strongly toward more MHC-dissimilar men. These immune genes may have a > "powerful effect in terms of how well relationships are cemented," says > University of Liverpool psychologist Craig Roberts, co-author of the August > paper. > > *Note: This article was originally published with the title, "A Tough Pill > to Swallow".* > > -- > gnothe se auton --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Memphis Freethought Alliance" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/memphisfreethoughtalliance?hl=en -~----------~----~----~----~------~----~------~--~---
