I chose Men Chase, Women Choose as the title for this book because I was looking for the fundamental biological premise that governs relationships. In nature the rule would be males chase, females choose. But, of course, I needed to “humanize” it. No one would want to read a dry essay on the abstract science of relationships. You want to know how this applies to your love life, and to explain this, we need to start at the most basic level.
Turn on any nature show and you’ll see the natural laws of courtship unfold before your eyes. You may see the bowerbird, so named because of the elaborate structure he builds called a bower. He spends weeks carefully constructing this stick-framed stage to entice the female. He decorates it with scraps of blue string and fabric, blue bits of plastic, like a blue straw or a candy wrapper, because he knows that blue is the female’s favorite color. He also adds shiny bits of bling, if he can find some. If a female happens to show an interest and investigates, he begins his courtship dance.
She’ll stand and judge him, as he genuflects, bows his head like an English gentleman of the court, then folds and twists his wings in a memorizing ballet. If she likes the dance (and the digs) she may stay, or she may fly from bower to bower looking for one that has just the perfect combination of stunning surroundings and exceptional performance. Only after she’s fully satisfied will she allow the relationship to advance.
In a different corner of the planet, you can see male walruses in a bloody battle defending a tiny strip of sand. They lunge their massive bodies, which weigh about the same as an average car and are equipped with two-foot-long, body-piercing tusks, at any interlopers that dare cross into their territory. Battles can be frequent and can leave the dominant male with many battle scars. During these battles, the females lazily lie back and watch the spectacle unfold. They don’t need to fight or worry. All they need to do is watch and then carefully choose the warrior they fancy.
All throughout nature you’ll see mutated male appendages increasing in size to provide an advantage: interesting physical characteristics and adaptations that help males fight for dominance, which is often a precursor to courtship. For example, the massive headgear of bighorn sheep are used to battle competing males when females go into estrus. These massive accoutrements can reach up to 15 percent of the ram’s body weight, weighing upward of thirty colossal, calorie-burning pounds. In addition, the horns can grow so long that they interfere with sight, forcing the rams to rub away the edges to see better. 12 In the fall, massive battles between males can be heard for miles as they bash horns in order to prove who the best “man” is. The male with the largest rack often wins the admiration of the females.
Horns are not the only male body part that have transformed in an attempt to fight for the affection of a female. The platypus, a duck-billed marsupial, has evolved a sharp ankle spur that’s used to fight other males for dominance, while the Japanese Otton frog has evolved something that’s usually only seen in comic book movie characters: a combat-ready fifth finger spike that’s used to ward off other male suitors.13
Of course, these guys are not alone. Males of many species battle other males for the attention of females. Fights between males for dominance can be seen with whitetail deer, antelope, bison, rhinoceroses, and, of course, at the local college bar on a Friday night.
In most species males compete with each other to prove to a female which one is uniquely qualified for the job. Males perform tests of skill, fight other males, serenade, build alluring houses, provide food, and act like an all-around nice guy to attract the attention and the potential affection of females.
NATURAL LAWS
Biologists study nature in hopes of discovering and defining laws. Laws are observations that hold true under every circumstance. For example, the law of gravity essentially says objects fall to the ground. Gravity affects everything on Earth and holds true in every situation.
Scientists look at a variety of natural phenomena to try to find patterns. When we find something in one species, we look to see if we find similar activity in other species. For example, many species migrate in the spring and fall. If we see a particular species heading south every year in October, we can make a safe prediction that this might be a migratory species.
Nature patterns tend to affect everything, including mammals, insects, birds, and humans. Like migration, there are other behaviors that are predictable between species. Some behaviors are so universal that we could make them into a law, like the law of gravity. Along that thought, if scientists were to establish a law for male–female relationships, particularly courtship, it could be “males chase, females choose.”
Recently, another dating coach I know became upset with me. He liked to advise his female clients to go ahead and pursue a man. He felt a woman should be able to e-mail a man or walk up to him and introduce herself if she wanted to. In fact, he insisted that my idea that men chase was old-fashioned and no longer applicable.
I understood his logic. Society rules have changed quite a bit over the last decades. Women have much greater autonomy and can do just about everything a man can do, including chase. But as I’ll explain in greater detail in Chapter 6, her chasing can have the unintended consequence of usurping his ability to fall in love.
For a woman looking for love, the golden rule is “men chase, women choose.” But don’t just take my word for it. Let’s ask Mother Nature. She has especially built men for the chase—and built women to be choosy.
HE’S BUILT TO PURSUE: THE GREAT AND MIGHTY TESTOSTERONE
Men are born with a very special, magical chemical that courses through their veins. This chemical has the ability to change and shape their bodies into a lean, mean, chasing machine. The name of this great compound is testosterone. Both men and women produce testosterone, but almost all men produce much more than women do. When looking at the differences between men and women, most look at visual signs or secondary sex characteristics. For example, women have breasts, fat layers that make them softer, and wider hips with a slightly uneven gait that produces that “wiggle in the walk that makes the world go round.” Men, on the other hand, have bigger muscles, narrow and solid hips, an Adam’s apple, and facial hair.
Brains are seldom taken into consideration when we’re looking at gender differences, but just as hormones make our bodies look different, the effect these hormones can have on the physical structures of our brains is just as dramatic. These neurological, structural differences affect our behavior in rather predictable ways, especially when it comes to relationships with the opposite sex.
MEN CHASE: COMPETITION
Testosterone persuades males to compete for the attention of females. Researchers have found that during courting, testosterone levels increase in most animals, including humans. To confirm that testosterone is linked to men’s ability to woo women, researchers from Wayne State University conducted an experiment. The study engaged pairs of men in a seven-minute competition for the attention of an attractive female. Precompetition testosterone levels were taken and found to be proportional to the man’s level of dominance. In other words, guys that tended to “take control” of the conversation or were more assertive had higher testosterone levels, whereas the more reserved men had lower testosterone levels.
Next, the researchers observed the male’s performance while competing for the woman’s attention. They discovered that higher testosterone levels had an influence on the man’s behavior. The men with higher testosterone levels were more aggressive toward the other competitors, showing dominance by denigrating the others.
Interestingly, at the same time, the woman reported that she “clicked” with the testosterone-laden men. The researchers concluded that the boost in testosterone provided an advantage during male rivalry, stating “our findings indicate that testosterone is associated with dominance behaviors and success when men compete for the attention of an attractive female.” 14
The potent testosterone provides males with the needed vigor to strive to win the ultimate prize—the female. But the desire to compete is not the only thing that prepares him for the chase. Just as his testosterone shapes his muscles and bones, they also shape his eyes and brain.
PEEKING IN HIS HEAD
Researchers at the City University of New York compared the vision of men and women with respect to color and movement. They found that men have greater sensitivity to rapidly moving stimuli. 15 Men are better at spotting things that are mobile. In other words, if you want him to notice you, it helps if you’re moving. That is to say, he’s built to chase.
These visual differences make perfect evolutionary sense. Taking a look at ancestral roles, the primitive man’s job was to hunt large animals. Back then he couldn’t just walk into the local grocery store and plunk down a couple of bucks and stroll out with a brisket. No, he had to first spot and then capture his dinner. Movement acuity was paramount. He needed to see that slight twitch of a tail, as dinner was trying to hide behind a bush.
What this means when it comes to dating is that he’s built to spot things that are moving, not standing in front of him, and then go after them. In other words, his vision prepares him for the pursuit.
But his vision is not the only anatomical difference that prepares him for the chase. He has several other structures in his brain that help him in his pursuit. One of the first places where you can see a difference between men’s and women’s brains is in the hypothalamus. The hypothalamus is a small part of the ancient brain. It’s only about the size of a pea, but it’s a critical structure when it comes to love. Not only is this tiny structure responsible for releasing the neurotransmitters needed for a man to fall in love, but it has a special spot called the “pursuit spot.”16
THE PURSUIT SPOT
Peering into a man’s brain, we find he has an area in his hypothalamus called the sexually dimorphic nucleus in the preoptic area (SDN-POA), or “pursuit spot.” This area of a man’s brain is two and a half times larger than a woman’s and is responsible for sexual response and the activation of male sexual behavior.17 This little structure is what goads him into stepping up for the challenge and starting the chase.
Research shows that the pursuit spot receives a variety of sensory input and has direct connections to motor pathways.18 In other words, when a guy spots a woman he’s interested in, his pursuit spot says, “Oh yeah, go get her,” then sends instructions to his feet to start moving in her direction.
The pursuit spot is the most conspicuous sexually distinct structure in the mammalian brain. It’s so large in males that researchers are able to tell the difference between a male rat’s and a female rat’s brain by simply looking at the size of it.19
This pursuit spot is highly sensitive to testosterone. In one study, researchers found that if they castrated a rat pup, half his pursuit spot neurons died within twenty-four hours, making his brain look like a female’s brain. By contrast, when the researchers gave androgens (testosterone) to a female, her pursuit spot grew as large as a male’s.20 In another study, researchers treated male rats prenatally with a substance that blocked the development of the pursuit spot in order to study the effects. They discovered that treated males showed less-masculine sexual behaviors, such as pursuits or mounts, and a reduced preference for a female over a male.21
A man’s testosterone-supercharged pursuit spot makes him biologically predisposed and ready and willing to chase. When a man spots a woman he’s interested in, he gets a jolt of testosterone. This in turn flips the switch on his pursuit spot. The next thing you know, he’s standing next to her saying, “I couldn’t help but notice . . .” His testosterone not only makes the pursuit spot in his hypothalamus bigger, it also changes the way he uses his hypothalamus.
THE MALE HYPOTHALAMUS
Both men and women have a hypothalamus, but each uses theirs in a slightly different way. Scientists at the University of California, San Francisco, found sixteen genes regulated by sex hormones that were expressed differently between the sexes in the hypothalamus.22
The hypothalamus is subdivided into regions, with each area having different functions. Both sexes have a dorsal premammillary nucleus (PMd) in their hypothalamus, but a man’s is larger and contains specialized circuits to detect territorial challenges. The hypothalamus is activated during the exposure of a perceived threat, and the PMd plays a pivotal role in amplifying this process.23 Like the walrus battling for his strip of sand, these specialized circuits in the hypothalamus make a man better prepared to acquire and defend his territory.
To confirm the theory that men are better at acquiring territory than women, a study at Stanford University School of Medicine conducted fMRI brain scans as groups of students played a video game. In the game, clicking balls accumulated points. In addition to the points, territory could be won or lost based on the position of the balls when clicked.
Researchers found that both men and women understood the game, and each wound up clicking on the same number of balls. The difference occurred in the amount of territory acquired. The men quickly realized which balls would provide them with the maximum amount of territory and began selectively choosing those balls. Women, on the other hand, didn’t seem as interested in acquiring the territory.
An analysis of the brain scans revealed that the men’s brains showed much greater activation of the reward circuit. In fact, the amount of activation was correlated with how much territory was gained, which was not the case for the women. In fact, the better connected a man’s reward circuit was, the better he performed in the game. The researchers say that the findings indicate that successfully acquiring territory in a computer game format is more rewarding for men than for women. As they conclude, it makes sense that men are more prone to getting hooked on video games than women.24 It’s also why men are better at the chase. It’s a primitive, almost subconscious response. Like the walruses and bighorn sheep, dominant territory-holding males usually have access to the most females. Of course, in humans, it’s not a strip of sand or an open field, but men with bigger homes and more resources do tend to have an advantage when attracting women.
In addition to the tendency to acquire resources, men have another part in their brain that tends to be larger than women’s and helps them to keep those resources: the amygdala.25
THE MIGHTY AMYGDALA
The amygdala is the brain structure associated with fear and aggression. The size of the amygdala varies in accordance with the amount of testosterone circulating in a man’s body. Scientists have found that hormone changes during adolescence create sex-dependent changes in the brain, making the amygdala volume increase significantly more in men than in women.26 This size difference helps to explain the behavioral disparities seen in men and women.
A man’s amygdala automatically scans the environment for any perceived threats. Because of his testosterone, a man’s brain can be like a government military post. His larger amygdala is equivalent to a high-power satellite surveillance system. He can pick up the smallest threat and prepare countermeasures, which may even include a preemptive strike.
A woman, on the other hand, usually has a much smaller amygdala. Her amygdala is more like the local neighborhood watch—a kindly older woman who keeps a lookout to make sure the kids are safe. She settles skirmishes with milk and cookies, and stern warnings (“Now, stop that!”). If she ever actually detected a real threat, her plan of action would not be to strike but rather to call someone else for help.
As Dr. Joo-Hyung Lee, who studies gender differences in brain function at the Prince Henry’s Institute in Melbourne, states, “historically males and females have been under different selection pressures which are reflected by the biochemical and behavioral differences between the sexes. The aggressive fight-or-flight reaction is more dominant in men, while women predominantly adopt a less aggressive tend-and-befriend response.” 27
The selective pressure that Lee is referring to is the ancient village life of the hunter and gatherer. In the ancient village, a man went out to do his hunting while a woman stayed at home to gather food and tend to the children. Everything was fine until one day when a group of strange men entered the village. The women had two choices: they could act aggressively or they could try to make friends with the strangers. Their best action was probably to be nice, serve them milk and cookies, and wait for the men to come back, because compared to the men, the women were not built to fight. The men, on the other hand, were better built to fight. So when they returned and saw their women with other men, their larger amygdalae sounded the alarm so loudly that they were ready to respond in seconds.
In addition to the amygdala, a man has additional brain structures that equip him to acquire and keep a woman, which we’ll explore below.
HIPPOCAMPUS
The limbic system contains a structure called the hippocampus. This little seahorse-shaped structure is part of the learning center and plays a key role in the formation of explicit long-term memory.28 In addition to memory, the hippocampus is used for spatial navigation.
One study found that men and women use different parts of their brains to maneuver through unfamiliar environments. The researchers used fMRI to measure brain activity while men and women navigated through unknown, three-dimensional mazes. Subjects were instructed only to find a way out of the maze. The study found that men were significantly faster than women at finding the way out of the maze. Looking at the brain scans, both sexes had neurological overlap, but there were two important differences, namely, that women engaged the right parietal and right prefrontal area, whereas men recruited the left hippocampal region.29 This means that women tended to think about where they were going, which may have slowed them down, while the men relied on a type of internal hippocampus GPS.
A research team at the University College London has discovered specialized grid cells in our hippocampus. These cells represent where an animal is located within its environment, something the researchers liken to having a satellite GPS in the brain. These cells were first discovered in a Norwegian lab in 2005, where researchers suggested that rats create virtual grids to help them orient themselves in their surroundings, and remember new locations in unfamiliar territory.
This operational difference between men and women makes evolutionary sense. If men were still clad in a loincloth, running out of the cave for a day of hunting, an internal GPS system would be critical. For example, say a prehistoric man spotted a succulent steak on four legs. In order for him to bring home his bounty, he may not just have to catch it, he might have to track his dinner for some time, venturing out over vast, unfamiliar terrain. Once he had tracked and caught his meal, he then had to remember how to get back home. Having an internal grid system that functioned like GPS without having to think about it would’ve helped him achieve that. That automatic part was important, since he still had to contend with other animals that would try to steal his and his hungry waiting brood’s dinner. Therefore, the man who had this ability would have had an advantage and would have evolutionarily been selected for.
But it wasn’t just for being a good provider that Mother Nature may have created these traits; it appears that the quintessential player may have used his hippocampus to his advantage. Researchers at the University of Utah studied the behavior of three species of voles. One species was polygynous and the other two were monogamous and stayed by their mates’ side. The scientists found that the hippocampus in the polygynous males was 11 percent bigger than that of the females of the same species, whereas the hippocampi in the monogamous males were about the same size as those of the females in that species.30 The polygynous vole needed a larger hippocampus in order to keep track of, and find the locations of, all his fine, furry females. His increased sexual activity caused an increase of testosterone, which increased his hippocampus, which then helped aid his philandering.
Testosterone levels tend to be proportional to sexual activity, with more sexually active men and women tending to have higher testosterone levels. In one study, testosterone deprivation caused a 40 percent decrease in synaptic density in the hippocampus, while testosterone replacement in male animals normalized synaptic density. This is to say, testosterone tends to supersize a guy’s hippocampus, helping him to remember where the women are.
Additionally, when male rodents were deprived of testosterone, their maze-learning performance was impaired.31 Therefore, it appears that the polygynous vole’s hippocampus evolved for both memory and navigation, increasing its size. Since he had more than one female, he had to remember where they were and how to get to them all. If you have a bunch of women to visit, you’re going to need a bigger hippocampus tracking system to remember where they all live.
WOMEN CHOOSE
In nature females are more selective because they take most of the risk when it comes to sex. Females must carry, give birth to, and feed the young produced. This is a huge responsibility that takes an enormous toll on health, time, and resources. If a female chooses poorly, she could potentially be doing all the work herself, putting her and her young at risk. If she chooses poor genes, she could potentially lose her children to illness. In order for her to have the best outcome possible, she must carefully scrutinize the myriad of applicants. Therefore, a female would never pursue a male. She would wait and carefully choose the best possible partner, as if her child’s life depended on it—because potentially it does.
If we distill a male and a female to an elemental basis of one cell, we would have the egg and a sperm. The sperm is the only cell in the human body that’s mobile. The egg doesn’t have to worry about finding a sperm. She knows that all she has to do is sit tight, relax, and any second, thousands of eager sperm will be in the race of their life to find her. These sea-men are especially built for this competition. They have been working out, in the testes, in a type of “sperm boot camp,” building stamina in the form of mitochondria for endurance to withstand the harsh environment in which the “female” resides. They have formed a specialized motility structure—the tail. They also come in force, wearing acidic helmets to break through the female barrier. It’s a tough job, but they were born for this. Just like the egg, the female in her entirety doesn’t have to worry if a male is coming. It’s not a question of “if” but “when.” I can confidently guarantee that you’ll never see an egg putting on a short skirt or low-cut blouse, hanging out in the ovaries or running around the town’s fallopian tubes trying to pick up random sperm. No, the egg knows she just needs to sit there as millions of excited little soldiers head her way.
The natural law of relationships is that the gender with the greater energetic investment in reproduction will be more discriminating when it comes to sex. Then the one with the least amount of energetic investment in reproduction will compete for access to the higher-investing individual. In most cases this means that males chase and females choose. However, this rule is not always drawn down gender lines. There are animals and insects out there where the male makes the larger energetic investment and is thus the choosier of the sexes. This is true of the bush cricket, sometimes called the “long-horned grasshopper.”
When the bush cricket mates, the male provides the female with a massive ejaculate that she not only uses to fertilize her eggs but also partially consumes, using it for energy. His sperm can represent up to one-tenth of her lifetime caloric intake. However, as you might imagine, in the process of producing this gigantic sex snack, the male can lose up to a quarter of his body weight. Put in human terms, it would be the equivalent of a man producing fifty pounds of semen in one ejaculation.
Not surprisingly, male brush crickets are very choosy when selecting a female to mate with. He looks for the healthiest female he can find and rejects smaller females that may produce relatively fewer young. As a consequence of this gamble he takes by risking so much of his energy, females must compete for his attention. In this case females actually spend a great deal of time courting him, proving that they are worthy.32 Since the gender taking the biggest risk gets to pick, in humans the woman does the choosing. And since she does the selection of different candidates, it means one wins while the others lose. But, more important, since she goes with the winner, it means she’s the prize.
WOMEN ARE THE PRIZE
As the prize, it’s a woman’s job to select the best candidate out of all the suitors vying for her attention. Therefore, Mother Nature has equipped her for this choosing. She has structural differences in her brain that are especially designed to help her pick. A woman’s eyesight, unlike a man’s, is designed to help her be choosier. Instead of grabbing moving objects, she’s better at carefully picking out things based on subtle variations, such as hues.33
A woman’s hippocampus is also used differently than a man’s. Similar to the way testosterone helped the man to chase, estrogen helps her to choose. Researchers have found that estrogen can activate the area in the hippocampus responsible for many aspects of learning and memory. In addition, hippocampal volume increases significantly only in females.34 Her hippocampus functions as a memory filer, sending memories to the appropriate areas for long-term storage and proper retrieval. This may provide women with better long-term memory. For example, compared to men, women recall longer and more detailed autobiographical memories, are more accurate at dating them, and are faster at recalling them.35
When you have to select from a number of suitors, you need to remember slight differences between them. That’s probably why Mother Nature made a woman’s hippocampus larger than a man’s.36 She remembers things, such as she likes suitor no. 1’s hair, but she thinks suitor no. 2 is funnier, and suitor no. 3 has a nice voice. She needs to remember, sort through, and recall these differences and traits properly.
OUR DIFFERENCES
The differences between men and women are important and necessary, because love and relationships are risky. The pursuer takes on a greater amount of risk in the beginning. Evolutionary biologists believe that men are hardwired to take risks for love. In a study conducted to see if men were inherently more willing to take risks once romantic elements were introduced, researchers discovered that men, but not women, were naturally inclined for these risks early on, and concluded that this tendency is rooted in evolution stating, “It appears that men have inherited this willingness to face dangers for women from our risk-friendly ancestors.” 37
Of course, both men and women experience risks in a relationship. But the timing and types of risks are different. Women take risks with becoming sexual. Therefore, in order for a man to experience excitement, he needs to take a different type of risk. His pleasure comes with the thrill of the chase. In other words, when a woman settles for something less than real courtship, both the man and the woman are robbed of this pleasure.
Now that I’ve hopefully convinced you that it’s a man’s job to chase and a woman’s job to choose, let’s get down to the business of love. But before we can get to love, we have to explore attraction.