Quotes from Helen Fisher

Real competition can drive up testosterone, which boosts libido.

Every time you cuddle with your children, you're likely to be driving down your testosterone.

In courtship, who wins and who loses will determine who passes on their DNA to tomorrow.

We are wired to find love.

You fall in love with somebody who fits within what I call your 'love map,' an unconscious list of traits that you build in childhood as you grow up. And I also think that you gravitate to certain people, actually, with somewhat complementary brain systems.

Women are better at reading body language everywhere in the world. As a matter of fact, it's associated with the female hormone estrogen. Women are better at figuring out of tone of voice, reading your face and posture and gesture.

Men want to think women don't cheat, and women want men to think they don't cheat, and therefore the sexes have been playing a little psychological game with each other.

You size up someone physically in less than one second - too tall, too short, too fat, too thin, too old, too young, too stuffy, too scruffy.

There are cognitive processes and limbic reactions associated with basic emotions. And you can change brain chemistry, but you're still not going to change memories and experiences in a human being.

Good-looking people are always looking for other good-looking people.

Women have a better sense of smell than men do, and it's even sharper in the middle of their menstrual cycle, when estrogen levels peak and women are more likely to be deciding whether a man's attractive.

Neither gender is routinely more jealous - although women are more willing to work to win back a lover, while men tend to flaunt their money and status and are more likely to walk out to protect their self-esteem or save face.

Women are very attracted to a low voice because it's linked to testosterone, which for millions of years was a sign that men had very good spacial skills and would have been very good at hunting and finding their way back home.

Today, most women are surrounded by ingenious gadgets. They don't grow the peas or raise the chicken that they serve for dinner; instead they hunt and gather in the grocery store. They go through catalogs or department stores to buy clothes instead of shearing sheep, carding wool, and weaving cloth for skirts and coats and blankets.

Your sweetheart calls you by another's name. His eyes linger too long on your best friend. He talks with excitement about a girl at work. And the fire catches. Jealousy - that sickening combination of possessiveness, suspicion, rage, and humiliation - can overtake your mind and threaten your very core as you contemplate your rival.

Once you fall for someone, their smell can be a powerful thing. Women will wear their boyfriends' T-shirts, and throughout tales in history men have held on to their lover's handkerchief.

It certainly would have been adaptive for ancestral man to have a chubby wife during stressful times of famine. Not only would she have had more calories to burn, and thus more energy and endurance, but since fat stores estrogen, she would have remained fertile for longer.

We evolved in a tropical climate where the smells of plants and flowers were all around us. We spent a lot of time in the trees with a lot of sunlight and no clothes.

A hundred years ago, if you had a child out of marriage, you'd be a social disgrace. Today women feel comfortable enough economically and culturally to bring up a child without a recognized commitment from a man.

I think you will find that with divorce will come happier remarriages.

When you can't have someone but you're not willing to accept that, you try harder and become more extreme about it. Either you win the person back or you drive him away.

In that early-love stage, you're in that state of exhilaration. You talk till dawn. You become obsessed with 'What does he think?' 'Does he like me?' 'Does he think I'm fat?'

You don't come home from the office to spend time with another job. Hopefully you come home to someone you can have a good time with.

Keep an open heart. We are wired to find love.