love: the toughest science

Why do you love me? \nIt's a question feared by boyfriends and girlfriends alike. \nWhen asked this question by your significant other, do you go with your gut response of "I just do," or search for a better answer then rattle off a list of generic qualities such as "your perfect smile" or "how you take care of me when I'm sick"?\nTurns out, it might be best to risk criticism for your lack of a "real" answer and go with your gut on this one. The answer really isn't that simple. \nA bevy of scientific studies have tried to answer the questions of what attracts one person to another person and what eventually causes some people to fall in love and some to fall out of love. Though science has provided some ideas, love and attraction are still very much a mystery. \n"Research is only starting to scratch the surface of love and attraction," said Erick Janssen, an associate scientist and director of graduate education at the Kinsey Institute for Research in Sex, Gender and Reproduction, and an adjunct professor in the department of psychological and brain sciences.\nSo why do we fall in love anyway? Why don't we pick our partners more sensibly? The answer, Janssen said, may have something to do with nature looking out for our best interests and something to do with just letting ourselves fall.\nHormones play an important role in falling in love.\nFalling in love causes a chemical reaction to take place in a person's body, providing a feeling of euphoria, said William Yarber, a professor of applied health science and gender studies and a senior research fellow at the Kinsey Institute.\n"It's like a drug," he said. "That's why people feel like the world is rosier and they get a little zip in their step." \nUnfortunately, our bodies build tolerance to the dopamine-causing euphoria, and the feeling fades. Some people have a hard time tolerating that. When the euphoric feeling disappears, they end the relationship. \n"Falling into it's the easy thing," Yarber said. "Staying in love -- that's the toughie." \nFrom the beginning of time, interaction between sexes has occurred among various species for one common purpose: reproduction. In some species, like the dung beetles biology professor Armin Moczek studies in his lab, reproduction is the only purpose for male and female interaction. \nBesides our choice of habitat and nutrient source, we have a lot in common with these beetles. Dung beetles dig tunnels under dung pads and carry pieces of the pad down with them to nourish their eggs.\nIn humans, as in beetles, mating behaviors are a product of evolution, Moczek said. Some male beetles have developed horns that help them fight off other male beetles trying to sneak into their tunnels to inseminate the female beetle already inseminated by the male guarding her tunnel. A male who lacks horns uses sneak tactics to gain access to the previously inseminated female to inseminate her himself. \n"In a wide range of organisms, including beetles, and sometimes humans, males can't help but beat the crap out of other males when it comes to females," Moczek said. "But by admitting a degree of biological determinism, I don't equate that with lack of control over our behavior."\nAlthough humans have more than just reproduction to gain from interaction with the opposite sex, several studies have shown successful reproduction is still an important, yet sometimes subconscious, driving force in determining who humans are attracted to.\nWhile attractiveness varies among cultural and personal tastes, a landmark 1951 survey by Clelland Ford and Frank Beach showed there are only two traits women and men consider universally appealing in terms of sexual attractiveness: youthfulness and good health. The reason? Finding a mate capable of producing one's offspring is an instinctive urge in all animals, including humans, according to sociobiologists. \nYarber adds physical attractiveness to the list of universally appealing traits. "If you see someone who's very attractive, you can pass those traits on to your offspring," he said.\nSongbirds seem to have a similar strategy. \nUnlike beetles, birds pick one "social partner" to mate with and care for their offspring for an entire year, said Nicki Gerlach, a graduate biology student studying the mating habits of dark-eyed juncos. But one-third of female birds end up mating with males they perceive as "more attractive" to father their offspring. \n"The attractive males usually don't lose any paternity at home but are gaining babies elsewhere," Gerlach said. \nFemales tend to be more attracted to male birds with more testosterone since they sing more often and strut around in displays of courtship frequently. But since more of their time is occupied courting females, females find them to be worse parents, and the "unattractive" birds still get the job of raising his social partners' offspring.\nIn humans, there's a lot of debate over what type of mate we're attracted to. Some theories say we look for people with traits similar to our own and our parents' -- they remind us of the intimacy we shared with our parents when we were babies. Yet others say we're attracted to people who are more genetically different than us to avoid inbreeding.\nAdrienne Evans, a graduate biology student, said she sees opposites at work in her six-year relationship with her live-in-boyfriend, Francis Fernandez. He's the quiet book nerd while she's the outspoken science geek. More importantly, his ancestors come from Spain, Ireland and Cuba and hers come from a pale British Isle background as well as Germany.\n"We probably don't have a common ancestor in there," she said. \nOr maybe attraction is even more subconscious than we think. Pheromones, odorless chemical substances released into the air by humans, are a topic of much debate among scientists. Pheromones work by arousing sexual interest in people who subconsciously perceive them, and some scientists say they still play a role in who we're attracted to. \nA commonly-quoted study of pheromones by Claus Wedekind that required women to smell men's worn T-shirts found women were most attracted to the genes most different from their own. \nBut other scientists say humans may not be able to detect pheromones at all.\n"We have the necessary equipment (the vomero nasal organ in the nose used to detect pheromones), but we don't know if it still works," Janssen said. \n So what does it take to make a relationship last? \nIt could be that your love maps match. John Money, a world-renowned sexologist, says humans are programmed before birth with a subconscious list of likes and dislikes depicting their perfect mate. These "love maps" cannot be controlled and are the reason one person seems to stand out in a crowded room. The closer another person fits your love map, the more likely your relationship will succeed. \nRelationships need to be in balance with Robert Sternberg's triangular theory of love in order to last. According to the theory, passion, intimacy and commitment are all required in order to have a successful and loving relationship. \nWhile passion can happen in an instant, intimacy and commitment take more time to develop, Yarber said. Passion can also fade more quickly, so it helps to be creative in keeping passion alive. \nRelationships that last are also more likely to be abundant with the hormone oxytocin or "the love drug," as Janssen calls it. Oxytocin promotes a feeling of bonding and contentment in couples. It can be released through a variety of ways, including during orgasm.\nSo is it science guiding us on our journeys through love?\n"In some ways I think yes, we're all animals. We're still programmed to breed and pass on our genetic material," Evans said. "But at the end of the day, you have to talk to that person and whether you're compatible outweighs all the biology"