The Rational Animal: How Evolution Made Us Smarter Than We Think (22 page)

Developmental psychologists Bruce Ellis and Jay Belsky have found that two aspects of our childhood environment are critical in determining our life history strategy.
First, strategies speed up if people grow up in dangerous environments—places rife with violence or disease.
A study of 170 different countries found that local mortality levels (the likelihood of death) were strongly related to the age at which mothers had children, with higher mortality leading to much earlier age at first birth.
In Niger, for example, which has the fourteenth-highest death rate in the world, over 50 percent of women have had their first child by age eighteen.
In Vietnam, which has a low death rate, 165th in the world, only 3 percent of women give birth by age eighteen.
Similarly, in a study of Chicago neighborhoods, the median age of mothers giving birth was 27.3 for the ten neighborhoods with the highest life expectancy but only 22.6 in the ten neighborhoods with the lowest life expectancy.
Life history strategies are not merely related to general crime.
When we examined records for 373 counties in the United States, we found that earlier age of first birth is specifically related to higher rates of physically dangerous violent crimes (homicide, assault, rape) but not property crime (theft, car theft, burglary).
And the patterns persisted even when controlling for income.

The second factor that speeds up life history strategies is being raised in a fluctuating environment.
Environmental fluctuations include frequently moving from place to place, having an unpredictable income, or seeing different people move in and out of the house.
For example, girls living in a household without a consistently present father figure start puberty earlier—they begin menstruating, on average, nine months before girls who have a consistently present father figure.
Earlier onset of menarche is a clear marker of a fast strategy.
Similarly, having an insecure and more unpredictable relationship with one’s mother in infancy is also linked to earlier onset of puberty.
And just like those of dangerous environments, the effects of fluctuating and unpredictable environments remain strong even when researchers
control for socioeconomic status or genetic factors, such as the mother’s own age of menarche.

Just as we saw for tenrecs, it has been evolutionarily adaptive for people in dangerous and unpredictable environments to follow a fast strategy.
Such environments are associated not only with a shorter lifespan but also with uncertainty about where resources are going to come from—or if there will be any resources at all.
A fast strategy emphasizes getting the rewards and cashing them in immediately.
In a dangerous and unpredictable environment, this can be adaptive, since you don’t know whether you’ll be around later to enjoy the benefits of compound interest on long-term investments.
For the same reason, investing time and energy in acquiring skills and knowledge (such as getting a college education) makes evolutionary sense only if a person expects to be around for a while.
If not, evolutionary success may be better served by foregoing the time, effort, and cost associated with education and instead expending those resources on tasks with more immediate evolutionary payoffs—like reproduction.

Our childhood environments serve as blueprints for what we can expect as adults.
When Jeff Simpson, Vlad, and their colleagues examined what kinds of childhood experiences were most associated with a fast strategy in adulthood, they found that the experience of living in a fluctuating environment during the preschool years was the strongest predictor of having more sexual partners, being more aggressive and delinquent, and having a criminal record as an adult.
The importance of the first five years suggests that even if our young minds are not consciously ready to analyze what’s happening around us, our brains are nevertheless encoding what’s going on.
If you’re being raised in a world where there is little you can do to avoid violence, and it’s impossible to know what tomorrow might bring, you need to make the most of today.
And if access to resources is unpredictable, a “get while the getting’s good” attitude may be evolutionarily adaptive.

It’s no coincidence that many people who live fast come from difficult childhoods.
MC Hammer, Mike Tyson, and Larry King have all lived fast.
They also all grew up in poor and dangerous neighborhoods (in the East Oakland projects and the tough Bedford-Stuyvesant and Bensonhurst neighborhoods of Brooklyn, respectively).
Each was
raised by a single mother after his father either abandoned the family or died, and each had to find ways to get what he needed (Tyson had already been arrested thirty-eight times by age thirteen).

These kinds of harsh and fluctuating early-life environments calibrate the brain to enact a fast strategy—the kind adaptive for evolutionary success when life is expected to be nasty, brutish, and short.
Looking through an evolutionary lens, it becomes clear why these three men started spending their monetary windfalls as soon as the money hit their bank accounts: their brains were calibrated to live fast because they did not know what tomorrow would bring.
Not only do the majority of people who win the lottery come from poor and unstable backgrounds, but many lottery winners go on to lose their fortunes within a few years.
By contrast, growing up in a safe, stable, and predictable environment calibrates the brain to enact a slow strategy.
It pays to go slow and steady when you know what’s coming next and you’re expecting to be around to reap the fruits of your labor.

Let’s reconsider the marshmallow test from earlier, in which kids were given the choice between having one marshmallow now or two marshmallows later.
Which choice is smarter?
From a life history perspective, the wisdom of waiting depends on the nature of your environment—on whether you live in a predictable or unpredictable world.

Scientists at the University of Rochester recently performed the marshmallow test once again, except they made the child’s environment either predictable or unpredictable.
Before giving the kids the test, a researcher first showed them a few crayons and promised that if they waited, they would get to play with a large box of fun art supplies.
In one condition, the researcher came back with the art supplies as promised.
But in another condition, the researcher came back with nothing, telling the children that he had made a mistake and there were no art supplies.
In both conditions, the kids were then offered the standard marshmallow deal.
As each child sat alone in the room looking at the treat, the researchers recorded how long each boy or girl waited before eating the marshmallow.

When the kids had experienced a predictable environment with the reliable person, they waited an average of twelve minutes before
grabbing the marshmallow.
But when they had instead experienced an unpredictable environment with the unreliable person, the children grabbed the marshmallow after just three minutes.
Children’s ability to delay gratification is not carved in stone.
Their brains adjust their impulsivity depending on their situation, in the same way that our adult life history strategies are adjusted depending on our childhood environments.

WIN, CRASH, OR BURN

So is it always wise to delay gratification and play it slow and steady?
Or might it be wiser instead to take large risks in hopes of winning big now?
From an evolutionary perspective, the answer depends on whether one is following a slow or a fast life history strategy.

If life were an athletic event, slow and fast strategists would be participating in completely different races.
Slow strategists are on a long march.
A defining feature of slow strategies is their low variance.
This means that few slow strategists will end up as millionaires, but few will end up bankrupt either.
Instead, there is relatively little variability in the slow game—the vast majority of such strategists find themselves somewhere in the middle, with decent, stable jobs, perhaps a white picket fence, and a small nest egg.
Slow strategists are the backbone of every community.
They include many of our teachers, administrators, nurses, middle managers, and accountants.
These are not freewheeling types throwing around money or swimming in massive amounts of debt.
They live within their means and expect to be alive to enjoy the fruits of their labor in retirement, when they finally get to cross the finish line of life’s long march.

Fast strategists, on the other hand, are racing in a sprint hurdle.
They have to dash rapidly and jump high in hopes of clearing the many impediments that are likely to trip them up.
A defining feature of fast strategies is their high variance.
Compared to those on the slow path, more fast strategists will come up from the streets to become millionaire movers and shakers.
These are the visionary artists, entertainers, and entrepreneurs—of both the legitimate and illegitimate varieties.
Through fearless enterprising, maniacal hard work, and a
lot of luck, some fast strategists like MC Hammer, Larry King, and Mike Tyson rise to the top.
But while a few fast strategists will taste success, even if for a short while, many more will crash and burn.
The same riskiness and shortsightedness that lead some to rise to the top lead many more into debt, debilitating addiction, or prison (Mike Tyson, for example, was prosecuted for rape, and Larry King was arrested for grand larceny).

Some fast strategists won’t even live long enough to spend their “easy-come” fortunes or go to prison.
That’s because living the fast life is inherently dangerous.
The same traits that produce ambitious entrepreneurs, visionary artists, and attention-grabbing entertainers can lead to massive health problems and tragic accidents.

At least fifty-three successful rock stars belong to the infamous “twenty-seven club” of rockers who lived fast, partied hard, and died at the age of twenty-seven.
These include raspy-voiced singer-songwriter Janis Joplin (heroin overdose), psychedelic guitar icon Jimi Hendrix (mixing alcohol with barbiturates), generational poet and Doors front man Jim Morrison (heart failure from a drug overdose), original Grateful Dead keyboardist Ron “Pigpen” McKernan (stomach hemorrhage from heavy drinking), eclectic singer Amy Winehouse (alcohol poisoning), and the original Rolling Stones guitarist Brian Jones (found at the bottom of a swimming pool, with the coroner’s report ruling that the cause was “death by misadventure”).

Whereas the average age of death in America is 75.8 years, one informal study of 321 rock stars found that their average age of death is 36.9 years.
Certainly not all rock stars die.
When Motley Crüe front man and “Dr.
Feelgood” singer Vince Neil crashed his exotic De Tomaso Pantera sports car while driving drunk in 1984, he lived—but he did kill his twenty-five-year-old passenger, Nicholas “Razzle” Dingley.
Neil managed to stay alive long enough to file for bankruptcy in 2005, despite selling over 80 million albums in his career.

Even if you’re not a rock star and don’t always live on the edge, your own fast or slow tendencies are likely etched deep into your psychology.
Animal research has found that tendencies imprinted in childhood are most likely to surface in times of stress and uncertainty.
In studies with Bonnet macaques, for example, adult monkeys respond
to stress very differently depending on their childhood environment.
After the monkeys were born, researchers had placed them in different environments.
Some were raised in stable and predictable environments (their mothers could obtain food every day in the same place in a predictable manner).
Other monkeys were placed in fluctuating environments (the researchers kept switching the locations of their food supply, so that the mothers didn’t know how, where, or when they were going to find food each day).
When the monkeys grew up and were exposed to stress as adults, those reared in a consistent and predictable environment coped well and explored multiple ways to deal with the situation; those reared in fluctuating and unpredictable environments panicked.

Research in Vlad’s laboratory has found a similar pattern in humans.
In these studies, some people first read stress-inducing news articles—daunting descriptions of recent economic recessions or increases in homicide.
Other people read calming news articles that didn’t induce any stress.
Then everyone was asked to make several choices that tapped into desires for risk and willingness to delay gratification.
For example, they could choose between receiving some real money for sure versus gambling for a larger amount (would they rather get $25 for sure or have a 50 percent chance of getting $40, for example).
Other questions gave them a choice between receiving some money tomorrow versus receiving a much larger amount in the future (would you rather get $25 tomorrow or get $60 in one year, for example).

When people read the calming news story, their choices were similar regardless of their childhood environment.
But reading the stressful news article produced markedly different responses, depending on the person’s childhood environment.
People raised in more predictable environments (as measured by having grown up in relatively wealthier homes) responded by adopting a slow strategy, avoiding gambles, and delaying gratification.
When stressed out, people who grew up relatively well-off wanted to go slow and steady.
By contrast, people raised in less predictable environments (as measured by having grown up in lower-income homes) responded to stress by adopting a faster strategy, preferring the gambles and becoming more impulsive.
When stressed out, people who grew up with fewer resources became more risk seeking and impatient.

Both the studies with monkeys and with humans show that childhood environments influence life history strategies.
Although tendencies associated with fast versus slow strategies might be dormant during good times, they emerge in times of stress.

OFF TO THE RACES

At the surface level, behaviors associated with fast strategies can seem wildly irrational and foolish.
Frittering away $30,000 a year on lottery tickets or buying a $2 million bathtub makes little sense when considered from the rational economist’s perspective.
Yet, like many of the other puzzling phenomena discussed in this book, impulsive behavior might reveal a deeper logic when you consider it from the evolutionary psychologist’s perspective.