By Victor Greto
I don’t really love you, you know. I’m just thinking with my hypothalamus.
Actually, I’m not “thinking” at all.
I’m just naturally drawn to your 68 percent waist-to-hip ratio. It means you’re fertile, at least on the surface.
And don’t tell me you’re in love with my brain. Whether I want to admit it or not, my physical makeup (not my endlessly fascinating intellect) is probably what attracted you to me.
So much for the concept of romance. What “romantic” love really is, say many biologists, is the need to procreate. We’re drawn together not by our intellect and emotions, but by chemicals, genes and the most ancient part of our brains. It is not about conscious choice or something as indeterminate and culturally driven as love.
Don’t believe it? Ask some of the researchers who study human sexuality for a living.
For starters, consider Dr. Robin Baker’s 1996 book, “Sperm Wars: The Evolutionary Logic of Love and Lust” (Fourth Estate).
“Why,” the good doctor asked, “in the midst of a perfectly happy and satisfying relationship, do we sometimes get an incredibly strong urge to be unfaithful? Why do men inseminate enough sperm at each intercourse to fertilize the entire population of the United States, twice over?”
Blame it on two fundamental drives: the urge to procreate and the search for the best genes to pass on to one’s progeny.
The central idea behind Baker’s book is that a major part of a male’s sexual behavior is geared — subconsciously — toward preventing his partner from exposing his sperm to competition or giving his sperm the best chance of winning a competition.
What competition?
Baker suggests women are genetically driven to desire more than one partner — especially at a certain time of the month — so they can assure fertilization. They don’t realize it, he says, but our bodies understand all of this on a subconscious level.
It also doesn’t mean that a woman will invariably act on those urges. But she’s more likely to get the urge at certain times.
“A woman,” he writes, “is much more likely to have penetrative sex with a man other than her partner during her fertile phase. Moreover, she is much less likely to use or insist on the man using contraception on such occasions.”
So a man produces millions of sperm to fend off the other guy’s sperm — whether there’s actually another guy or not. Baker’s “sperm wars” refer to the evidence that a male’s ejaculation (on average, about 300-500 million sperm) is made up of different varieties: from the “egg-getters,” whose job is to fertilize the egg; to the “killer” sperm, which live to kill other men’s sperm that got there before them; to “blocker” sperm, which live to block foreign sperm introduced since they got there.
Men also want to procreate as much as possible, and will subconsciously desire multiple partners, even if they don’t think they do.
Baker isn’t the only scientist to promote these deterministic ideas, though he’s one of the more renowned.
Robert Friar, a Michigan professor and longtime member of the Society for the Scientific Study of Sexuality, says the evidence he’s seen about sperm warfare “appears” to be right.
But, he says, “in science, nothing is ever guaranteed to be correct.”
But the evidence is compelling — as well as the evidence for another source of human sexual behavior.
Take recent studies concerning the hypothalamus, the most ancient part of our brain.
“It’s been unchanged in 5 million years,” Friar says. “The chimpanzee has a highly similar hypothalamus.”
Friar said that nearly 5 million years ago, we split from the chimp line and developed a cerebrum, which allows us to think and reason and make choices — and rationalize our subconscious urges. But there’s still no denying the power of the hypothalamus.
“Women and men both are attracted to particular traits cross-culturally,” Friar says, citing numerous sociological studies. “Men will select a woman with a waist-to-hip ratio of 68 percent.” That is, a waist that’s 68 percent the size of the hips.
Why? Because estrogen deposits fat on the hips and breasts. Subconsciously, men are attracted to an ideal image of a woman high in estrogen and who’s fertile.”
What are women attracted to in men?
“Positions of power. They also choose men who have broader shoulders, a thin waist and larger muscles.”
The reasons for this, many scientists argue, are the millions of years our ancestors spent in a hunting-gathering society.
“A woman who is seven months pregnant in a hunting-gathering society can’t get food and protect herself. When the baby is born, she carries the child with one arm and is not as free, so she chooses men who are bigger,” Friar says.
This is also why many women flock after professional athletes and rock stars, he says. If a man has a position of power and money, he’s more attractive.
“This is all driven by the hypothalamus,” Friar says. In other words, it’s subconscious.
But we’re not in a hunter-gathering society anymore, you may protest. Yet we were for millions of years. Chalk it up to this: It’s hard to break old habits.
So, is there such a thing as love?
Sort of. But it’s chemical, Friar says.
“There’s a neurotransmitter called phenylethylamine (PEA), which was discovered only five years or so ago,” Friar says. “This is what makes us fall in love, see the person’s strengths and not their weaknesses.”
He also says that we’re subconsciously influenced by those near and dear to us, and will choose our mates based on those characteristics.
“Who you fall in love with is also predetermined,” he says. “It’s going to be the sum total of all those persons you’ve known in your lifetime: traits you knew in your mother, teacher — both physical and mental — the way she smiles, the color of her eyes.”