Whatever it is about the opposite sex -- or same sex, for that matter -- that gets your engine purring, it seems there's more than pure hormones to blame for our horniness.

Psychologists have unlocked the science behind that stirring in our loins when we first clap eyes on a potential partner. And it turns out that beauty isn't just in the eye of the beholder, it goes right down to their generational genes.

Top psychologists Viren Swami and Adrian Furnham unpeel the layers of physical attraction in new book, "The Psychology of Human Attraction."

And they have discovered that, far from being skin deep, the changing perception of beauty is as entrenched in evolution as discovering what our hind legs are for.

The study looks at how evolution has affected what's considered to be hot and what's not in the modern dating and mating game.

And according to Viren Swami, we've gone from fancying rugged Tarzan types to perfectly polished Brad Pitt, voluptuous Venus de Milo to super-slim Kate Moss.

"The idea behind the evolutionary psychology of physical attraction is quite simple," he says. "We've all evolved to find other humans attractive. But the cues for recognizing beauty have changed over the years.

"We still look out for things like signs of health -- a symmetrical face, for example -- even though conditions have changed and we're not constantly under threat from disease.

"However, these days we judge people first by body size and then by facial characteristics, much more so than old-fashioned barometers of beauty, like symmetry."

And the bad news is if you've eaten one too many mince pies over the festive period, you can't have expected to pull under the mistletoe.

The study showed that when it comes to waistlines, we're a shallow bunch after all.

"The majority of our participants admitted that they would be more likely to help an average weight victim of a road crash than an underweight or overweight one," Viren says. "Likewise, workers who are a normal weight are considered harder workers, get better starting packets and are less likely to get fired.

"So, yes, it seems most people prefer someone who is thin to someone who is overweight. Within that, though, there are individual preferences towards someone who's on the underweight or slightly plumper side."

But even if you're a perfect 10 or sport a six-pack, you may still be deemed a minger thanks to today's impossible standards, according to the author.

Unlike our ancestors, who cruised for glowing girls and burly blokes who looked like they could fight off the plague and produce offspring without a problem, these days only A-list looks will turn heads.

Celebrity culture has skewed our perception of beauty in favor of pneumatic pop babes and airbrushed actors. "We're bombarded with the idea that certain individuals are attractive," Viren explains. "It's fair to say that within particular cultures, most people share an ideal of who or what is beautiful. Some argue that it's a biological thing -- that we share the same genes so we have the same perception of beauty.

"But the likely explanation is that we live in the same society and so are exposed to the same ideal through celebrities.

"In the Western world, for example, it would be almost unnatural not to consider a busty blonde like Pamela Anderson attractive."

However, if you're not a double for Angelina or a Colin Farrell lookalike, don't throw in the romantic towel just yet. There's always the option of long-distance love -- what doesn't float boats here can set pulses racing elsewhere.

"The most important factor in determining what we find attractive is the society we live in," Viren adds. "Body size is the best example of that -- in the developing world larger bodies are still seen as attractive, whereas in the developed world skinny bodies are desired.

"Darwin had a whole list of beauty practices that people did in different cultures to make themselves more attractive, like people in Borneo who filed their teeth to make them blunter because it was thought to be beautiful.

"What's deemed to be attractive is the norm within that particular culture."

And while we're more likely to opt for teeth whitening than filing on this side of the world, the psychologists argue in their book that we're tinkering with notions of beauty in far more sinister ways. Evolutionary expert Viren reckons that plastic surgery is set to distort ideals of beauty even more for future generations. "The short answer is that we don't know what effect plastic surgery will have on the evolution of what it means to be attractive," he says.

"But the idea that we have to change our body to fit an ideal is a problem in the first place. The whole idea of ideals is ridiculous. There's no such thing as perfection.

"So much emphasis has been placed on appearance that it's almost normal to feel negative about your body. It's difficult to say where we go from here."

And he urged people to rediscover the joy of sticky-out ears and spare tyres, instead of aspiring to bag or become one of the beautiful people.

"We need to rediscover the meaning of beauty and ways of finding beauty in different places. In real life, I think most people don't end up with a Pamela Anderson type.

"We have to ask why we place so much emphasis on appearance and who stands to gain.

"In the 70s, feminist authors wrote about cosmetics companies having a vested interest in ensuring women felt bad about their bodies.

"It may be a little more complex than that but there are certainly vested interests maintaining the idea that we're not perfect, but should be. We need to start challenging that.

"As a society, we've lost the meaning of beauty."

Source: Belfast Telegraph. Provided by ProQuest Information and Learning. Powered by YellowBrix.

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