Springtime is just over the horizon. Nature is back at square one in its reproductive cycle. For animals, it is as simple as sniffing out that perfect mate; but for humans, love can be a rather complex process. For some, love comes at first sight; but, psychologist Rachel Herz, a professor at Brown University and author of The Scent of Desire, has compelling research that explains love, or actually attraction, through the old reliable olfactory system. Can it be as simple as love at first...smell? Is attraction as easy as animals make it look? Has society overlooked one of nature's basic methods of observation in favor of a more intellectual approach? Love can be ill defined, even in the literary sense, but science has managed to find a way to bring a complex emotion into the most simplistic of terms, something that many find far too reductionists.
The science behind attraction lies in our genes, specifically a group of over one hundred immune system genes known as MHC, or major histocompatibility complex. Men and women, whose MHC are distinct from one another, have a better chance at successfully reproducing than those whose MHC are similar to one another. This is because differing MHC lead to more disease-resistant offspring. In 1995, biologist Claus Wedekind, of the University of Lusanna in Switzerland, conducted the now dubbed "Sweaty T-shirt Experiment," which generated favorable results to the human pheromone argument. Forty-four men were given shirts to wear, as well as scent-free deodorant, soap, and aftershave, to use over the span of two days. Forty-nine women were then asked to sniff the shirts and rate the men on their attractiveness, based purely on scent. The results showed that women preferred the smell of T-shirts worn by men who were "immunologically dissimilar to them." Also, the scents reminded women of past and current boyfriends, leading Elizabeth Svoboda, of Psychology Today, to suggest in her article "Scents and Sensibility," that MHC is a component in women's dating choices.
Sexual chemistry, with the technological advances in society, has become a major, and for some the utmost important, component of finding love in this day in age; but, with such advances come unintended repercussions. According to Svoboda, Herz relates MHC to sexual chemistry, and for women who are on birth control, the effects of the pill can be disastrous in finding the perfect mate. In the same sweaty T-shirt experiment, one notable exception to the rule of MHC mating was that of women on the pill; women on the pill preferred the T-shirts of men whose MHC profile was similar to theirs. Charles Wysocki, a biopsychologist at Florida State University, explains that this poses a problem when women get off birth control to have children: "on a subconscious level, her brain is realizing a mistake was made-she married the wrong guy." To further complicate matters, women who are on the pill also emit scents which can be misconstrued by men as incompatible.
On the other side of the spectrum, an experiment conducted by Geoffrey Miller, an evolutionary psychologist at the University of New Mexico and author of The Mating Mind, showed that men preferred women who were not on the pill. In this experiment, exotic dancers who were not on the pill were making nearly fifty percent more on tips than their pill-taking counterparts. The reason, as Miller points out, could be that "women are probably doing something unconsciously, and men are responding to it unconsciously...we just don't know whether it has to do with a shift in their psychology, their tone of voice, or if it's physical, as in the kind of pheromones they're putting out." An added extraneous variable to the experiment were women who were ovulating at the time of the experiment, who, as the study showed, were the biggest earners. As Svoboda investigated, "other studies have shown that men rate women smelling best when they are at the most fertile," adding further to the argument of scent-induced attraction.
In "Chemical Compatibility," an article in The Providence Journal, Bryan Rourke reports on Eric Holzle, a scientist and engineer with an MBA, who started the dotcom business scientificmatch.com, to match couples based on their MHC makeup, as well as personal preferences and values. Not only was he inspired by the "sweaty T-shirt experiment," but he was nearly robbed of that chance by Herz, who's idea was deterred by her informal market research.
Moreover, the use of fragrances in hygienic products has also muddled nature's olfactory design. Ironically, companies market hygienic products as alluring to the opposite sex. Interestingly enough, Svoboda's research shows that some people choose store-bought fragrances that complement one's own scent. It is also important to note that it is nearly impossible for partners to go without getting a real sense of their partner's scent, especially in long-term commitments.
While genetics does play a role in the success of a successful pregnancy, relationships are far more complex to rely its success on the basis of genetics. Humans possess the intellectual ability to determine their soul mate based on a myriad of aspects, and not just their senses. That it is not to say that genetics should be discounted; in fact, if it is as simple as smelling out that perfect match among the plethora of people in society, some might have an easier time scoping out their future spouse! MHC, or any attraction by scent in the human population, can not be fully responsible for every relationship that malfunctions, or all unsuccessful pregnancies for that matter. Beauty has always been in the eye of the beholder, but now it seems as though scent must also be accounted for.