In chapter three of The Descent of Man, Charles Darwin wrote:
At the moment of action, man will no doubt be apt to follow the stronger impulse; and though this may occasionally prompt him to the noblest deeds, it will far more commonly lead him to gratify his own desires at the expense of other men. But after their gratification, when past and weaker impressions are contrasted with the ever-enduring social instincts, retribution will surely come. Man will then feel dissatisfied with himself, and will resolve with more or less force to act differently for the future. This is conscience; for conscience looks backwards and judges past actions, inducing that kind of dissatisfaction, which if weak we call regret, and if severe remorse.
But we also have to recognize that communication may be deceptive. People may bluff Also, communications are imperfect- mistakes are made or intentions are misunderstood.
The strategy that is effective in the long run is a modern version of"a tooth for a tooth" or TIT-FOR-TAT. It says that we should cooperate at the first meeting and then do whatever our "opponent" did the last time. When our opponent
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cooperates, we should cooperate. When our opponent doesn't cooperate, we should retaliate. Then forgive and go back to cooperating next round. This rewards past cooperation and punishes past defection. This assumes that the game is repeated time after time. In reality we never know if we meet our opponent again in the future. As long as neither our opponent nor we knows when the game ends, it pays to be nice. Of course, the game of the Prisoner's Dilemma is only a two-player game. Reality often involves many-person interactions.
There is one group that scientists say we treat better than others - our close genetic relatives. This is kin selection. We act altruistic to our kin because they share our genes. Studies show that in all social species, relatives are more likely to help each other. The greater degree ofgenetic relatedness between two individuals, the more likely it is that an individual treats the other individual better. If you sacrifice something for your children, it may harm you but since your children share your genes, the overall effect is positive. Scientists say that one test of kin selection is what we would do if a relative and a good friend were both close to drowning. We can only save one of them. What if oneof them was adistant cousin that you'd seen only twice in your life and the friend was a person you spent every day with? Who would you save?
What other behavior was appropriate for our ancestors?
A tendency for fear
Our fears are always more numerous than our dangers.
- Lucius Annaeus Seneca (Roman philosopher, c.4 BC-65 AD)
The passengers boarded flight 651 to Chicago. Two hours after takeoff, the flight attendant heard suspicious noise ftom the lavatory. The passengers started to talk among themselves. Panic erupted.
We fear dramatic and threatening events. We fear the loss of our health, family, friends, security, money, social status, power, or jobs. We also fear violence, crime, punishment, rejection, failure, the unknown, the immediate, the unpredictable or the uncontrollable. Studies show that even witnessing a traumatic event can produce the same fear response as experiencing the event ourselves.
Fear is our most basic emotion. Fear has evolved to help us anticipate danger and avoid pain. As science writer Rush Dozier writes in Fear Itself "Fear is fundamental because life is fundamental. If we die, everything else becomes irrelevant."
Humans have developed a strong emotion for fear. Our ancestors environment was fraught with dangers. Fear of physical danger, social disapproval, lack of food,
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no mate, predators, etc. Self-survival was a powerful incentive. Mistakes could be extremely costly. Assume two individuals heard a strange sound behind the bushes. One of them looked behind the bushes, was bit by a poisonous snake and died. The other one saw what happened, ran away and survived. To always assume there was a threat behind the bushes and run away could save an individual's life. The cost of being wrong and running when there was no snake was minimal. But the cost of staying around when there was a snake could be life threatening. Failure to detect threats is often more costly than false alarms. Our ancestors learned through trial and error that in the long run, pain could be avoided if they were fearful. They survived the dangers because they learned how to respond.
If pain and pleasure are guides to the behavior that leads to survival and
reproduction, fear is our biological warning signal for avoiding pain. Fear warns us of potential harm and keeps us from acting in self-destructive ways. It helps us avoid threats and makes us act to prevent further damage. Fear guides us to avoid what didn't work in the past. Fear causes worry and anxiety, a normal response to physical danger. It activates hormones like adrenaline and cortisol, which keeps us attentive to harm since we need full attention to escape from a threat.
The degree of fear we feel depends on our interpretation of the threat and our perception of control. The more helpless and vulnerable we feel, the stronger our emotion for fear becomes.
Assume that you are walking alone late at night on a deserted street in New York City. Suddenly, you hear steps behind you. What happens? Immediately you fear the worst - robbery, assault, etc. Your autonomic nervous system takes over and prepares you for fight or flight. Your response begins in your brain and activates a biochemical process. Your heart rate, breathing, blood pressure, pulse and blood sugar increase. Normal behavior when you are the victim of stress, either perceived or real. You reacted with fear on the deserted street because evolution equipped your brain to register pain more sensitively than any other emotion. You were using the "memory" of your ancestral past - your primitive fear system of fight or flight.
What we fear and the strength of our reaction depend on our genes, life experiences, and the specific situation. You may react instinctively at first, but if the situation is one that you've experienced before (since our brain is continuously being "rewired" with life experiences), the final reaction may be to calm down. You could turn around to find an old lady walking her dog. Or you may run away, because you avoid situations that in the past have been painful. The more we are exposed to a stimulus, even a terrifying one, the higher our
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threshold of fear becomes. If you for example had walked the same deserted street many times before but found out each time that the noise was the old lady walking her dog, you would be less careful. Until something terrifying happened. Often our emotions provide affective information that helps us make better decisions. For example, guilt may make us regret doing wrong things, and correct them. It may also induce cooperation. Disgust seems to be a response to danger to protect us from disease or harm. Shame may help us avoid certain temptations or reduce the risk of group-conflict. People who can't experience emotional responses because of brain damage seem unable to learn from their mistakes or
to make choices in a coherent manner.
Seeking explanations
'1 ate a plant and now I feel sick. Therefore, I believe the plant was not good for me. " In chapter two of The Descent of Man, Charles Darwin wrote: ''As soon as the important faculties of the imagination, wonder, and curiosity, together with some power of reasoning, had become partially developed, man would naturally have craved to understand what was passing around him."
We don't like uncertainty or the unknown. We need to categorize, classify, organize, and structure the world. Categorizing ideas and objects helps us to recognize, differentiate and understand. It simplifies life. To understand and control our environment helps us to deal with the future. We want to know how and why things happen and what is going to happen in the future. To understand how an event happened helps us predict how it could happen again. This is why we always look for patterns and causal relationships among objects, actions, and situations. This makes it easier to identify and understand things and to make predictions based on similarities in patterns. Finding and recognizing connections between things and events in our environment helps us to learn
what does and does not work. Patterns also give us comfort, making our need to find them even more important.
To learn what works and does not and what is good or bad for us means we have to explore. Exploring our environment successfully enables our survival and reproduction.
Remembering places, facts and events is important. But sometimes, the brain seems particularly attracted to new information and novel experiences. Recent studies suggest that the brain responds to novelty. The unknown is potentially rewarding, thereby motivating us to explore our environment and learn for the future.
We must be flexible in order to deal with constant change and unpredictability. We often explore the unknown in a random fashion. For example, many animals,
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when foraging, start with a random search, and only change their behavior when they find a rewarding stimulus. Then they move towards it.
Being flexible and learning a variety of options to choose from to deal with the world is of great value. This implies that finding new ways to deal with the world is superior to overtraining old patterns. For example, studies of honeybees show that they navigate according to a map-like organization of spatial memory. When bees are over-trained to find a single nectar site, it is easy for them to find their way back to the hive from that site, but not very well from other sites. But when the same bees are trained to many nectar sites, they are much better in finding their way home to the hive from a range of different locations. Further studies suggest that we learn better when we mix new information with what we already know.
Making fast classifications
There is a story about a man who went to visit a professor at his home. Outside the house a dog was playing on the lawn. When the professor opened the door to let the man in, the dog ran into the house. Later the professor asked the man, "Do you always travel with your dog?" The man replied, "It's not my dog. I thought it was yours."
Our brain is wired to perceive before it thinks - to use emotions before reason. fu a consequence of our tendency for fear, fast classifications come naturally. Limited time and knowledge in a dangerous and scarce environment made hasty generalizations and stereotyping vital for survival. Waiting and weighing evidence could mean death. Don't we often draw fast conclusions, act on impulse and use our emotions to form quick impressions and judgments?
We are especially wary of things that move. They may imply danger. That is why we automatically assume agency - someone was responsible - when we detect motion. Better safe than sorry.
Males and females have different priorities
"What is the brain for?" asked Neuroscience Professor Michael Gazzaniga in The Mind's Past. "The smart-aleck answer to the question is sex. Put more completely, the brain exists to make better decisions about how to enhance reproductive success." Reproduction is the central act in the life of every living thing. Once an individual has survived past the age of reproduction, the individual is evolutionarily useless.
The struggle to reproduce can sometimes have peculiar effects. In nature, things are not always what they seem.
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An ant climbs to the top ofa grass stem, falls down and tries again and again... until a sheep comes along and eats the grass (and the ant}. WHY does the ant persist in climbing the grass? How does the ant benefit?
There is no benefit to the ant. Its behavior was manipulated by a parasitic flatworm that needed to get into the gut of the sheep in order to reproduce. By commandeering its intermediate ant host to climb to the tips of the grass blades, the parasite increased the ant's chances of being eaten by a grazing animal. The benefit was to the reproductive success of the parasite, not the ant. Another parasite, Toxoplasma, can only reproduce within cats. It causes rats to lose their inherited fear of cats (cat scent) and thereby makes the rat more likely to end up as cat dinner. Another parasite causes fish to swim in shallow waters so birds can eat them, this parasite's final host.
Most animals (including humans) do something to attract the opposite sex. Since natural selection is ultimately about reproduction in a world of limited mates, some individuals were better at getting mates than others. The individuals that had an advantage in attracting prospective mates were "selected." What characteristics gave them the advantage? What anatomical features or behavioral traits attract the opposite sex or intimidate rivals?
Darwin realized that many anatomical and behavioral characteristics didn't have any survival value but could play an important role in attracting mates. Strength and beauty were such signals. He called this mechanism sexual selection. It has for example been shown that colors spark sexual interest among butterflies. And peahens prefer peacocks with big, colorful tails.
In Parental Investment and Sexual Selection, biologist Robert Trivers says that
the force behind sexual selection is parental investment, or "any investment by the parent in an individual offspring that increases the offspring's chance of surviving (and hence reproductive success) at the cost of the parent's ability to invest in other offspring."
Men need to attract women. But they also need to keep other men away from "their" woman. A woman must invest in each of her children. There is a nine month pregnancy and thereafter many years of child-caring. She invests time, energy and increases her chance of earlier death. There are limits to how many children she can produce during her lifetime. A man has less costs of reproduction. He can interact with many women and produce an enormous amount of children. He doesn't need to be around all the time. Many women can raise their children without help.
Since the goal of evolution is reproduction, a man should want to have sex with as many women as possible. This causes competition among men for women.
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How does a man eliminate this competition? He can either make himself more attractive to the woman or he can eliminate or reduce the competition.
The reproductive success of women doesn't depend on how many men she has sex with, but on her ability to get access to resources (like food, shelter, and protection) for herself and her children. Women are therefore more discriminating than men. She won't pick the first guy around. This causes women to compete with each other for access to resources. A man that is perceived as wealthy and having status has an advantage. So mating choices (showing up as unconscious preferences) are influenced by the fact that women have more at stake than men do.
In 1989, Psychology Professor David Buss published a study of thousands of men and women from 37 cultures around the world showing the ranking of qualities that are most important in choosing someone to date or marry. Women placed more emphasis on a potential mate's financial prospects. Women also preferred ambitious and industrious men. Women preferred older men. Men preferred younger women. Men ranked physical attractiveness higher than women did. The study also showed that a man felt most jealous when his woman was having sex with someone else. A woman felt most jealous when her man became emotionally attached to someone else.
Studies show other differences between the sexes. Women are less inclined to take risks. They are more influenced by the chance of loss. They are less competitive and status-conscious. Other studies show that men and women differ in their behavioral and cognitive capabilities. Some of this reflects varying hormonal influences on brain development. Like most things, this is context dependent.
The Social Animal
We do not care about our reputation in towns where we are only passing through. But when we have to stay sorne tirne we do care. How rnuch tirne does it take?A tirne proportionate to our vain and paltry existence.
- Blaise Pascal (French mathematician and philosopher, 1623-1662)
Isn't it likely that a good reputation, status, resources and being socially accepted helped our ancestors survive, get a mate, and reproduce?
In a small hunter-gatherer society, what was good for the group often paid off for the individual. Cooperation was critical in an environment with limited resources, individual weaknesses and many dangers. Isolation from a grou
p or society could mean destruction. There was safety in numbers. The group protected the individual against predators, hunted together, exchanged
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information about where food was, cooperated to defend food from enemies, and was a key resource for mates and help with infants. Together the group stood a greater chance of survival.
If we help another member of the small society, he may help us when we need it. If he doesn't, we may never help him again. This behavior is called reciprocation
- the idea of "I scratch your back and you scratch mine." A reputation for being reliable and trustworthy is important because how we acted in the past is the only guide to how we act in the future. Ifwe fool someone, he tells his friends, destroying our future possibilities for cooperation with others. Isn't that why we trust our friends but are careful when we meet strangers whom we know nothing about?
We have a strong concern for fairness. We get upset when things are unfair. We sometimes even punish others at a cost to ourselves. Maybe we don't want to appear weak or easily taken advantage 0£ Since we evolved in small communities with repeated interactions, it made sense to build up a reputation for not appearing weak. We wanted to encourage people to treat us better the next time around.
What happens if we help someone but the next time we need help, this person conveniently disappears? What about people who don't return favors? True reciprocity only works if (1) we live in the same small society so we recognize each other, can keep track of "services" given and received, and have future opportunities to interact, and (2) the cost of the act is pretty much the same as the future favor the recipient receives. One-shot encounters encourage selfishness as told by Biology Professor Lee Alan Dugatkin:
Seeking Wisdom Page 5
