Download The Biology of Human Behavior2

The Biology of
Human Behavior
by Dana Visalli
How far can the natural sciences, through the insight provided by evolutionary theory, penetrate into the
causes of human nature, and what is the impact of an evolutionary explanation of human behavior?
It is only recently that we have come to appreciate that a large percentage of the form and function of nearly
all organisms is controlled by the genetic code passed down from generation to generation, and that this code
has evolved its instructions through time as specific adaptations to specific environmental problems and potentialities. Homo sapiens, although perhaps the most adaptable single species on earth (i.e., with remarkable learning and behavioral latitude) has none- the-less evolved in the same environment and according to the same rules
as all other organisms. If this is so, what can we learn about ourselves by scrutinizing human behaviors in the
light of natural selection?
What is evolutionary theory? Biologist R.D. Alexander defines it by first noting that the following are facts
of life: 1) the inheritance of genetic code for form and function in all organisms, 2) sexual recombination and
random mutations of this genetic code, producing endless variation in succeeding generations, 3) natural selection, that is, the demands of the environment in which organisms live will select from this endless genetic variety those organisms best suited to survive and reproduce. Alexander then states that the interaction of these
phenomena (inheritance, recombination, selection) "and the successions of environments in which organisms
have lived account for the traits and history of all forms of life." Natural selection is the driving agent in evolution because it has a directional component; traits are selected because they are adaptive to explicit circumstances. This theory may sound simplistic, but it is in fact quite profound in that it indicates that there is an
explanation for all existing traits and behaviors, at least up to those ill- defined borders at which consciousness
begins to override the genetic program.
Many sociobiologists (sociobiology: the systematic study of the biological basis of all forms of social
behavior) think that this is a basic truth of human nature (however unappealing): If humankind evolved by
natural selection, then genetic chance and environmental necessity, not God, made the species. We are biological and our souls cannot fly
free. If evolutionary theory is the whole truth, then
species have a vast potential for material and mental
X
progress, but they lack any immanent purpose or even
an evolutionary goal toward which they are steered.
And if the brain evolved by natural selection, even the
capacities for esthetic judgments and religious beliefs
must have arisen by the same mechanistic process.
The brain exists because it promotes the survival and
multiplication of genes that direct its assembly. It is a
device for survival and reproduction, and reason is just
one of its various techniques. The venerable question
of whether nature or nurture makes the man must be
answered quantitatively; not if, but to what extent human social behavior is genetically determined .
Geneticist Conrad Waddington compared the relationship of the inherited and acquired behavior in humans to the topography of a landscape. For some
physical traits like eye color the topography is a single
deep channel. Once egg and sperm meet only one eye
color is possible. The adaptive topography of human
behavior is enormously broader and more complicatThe English peppered moth is one of the classic examples of the simple
ed, but it is still a topography. Even many behaviors
biological process of natural selection. The theory of natural selection
are similar in form across culture, suggesting that even
states that 1) offspring are variable (largely due to recombination of
behavior follows a well defined path. For example,
chromosomes during reproduction), 2) all species have more offspring
than can survive, and 3) on average, those individuals that are best
American psychologist Paul Ekman showed pictures
adapted to the current environment (which keeps changing) will endure.
of facial expressions to children of American and of
Prior to 1850 almost all English peppered moths were white, there was a
rare dark form as well. The white moths were camouflaged when reststone age cultures; 80% of the children in both recoging on light-colored bark (top picture, there is an X on the white moth).
nized the emotion being expressed in the face of the
After 1850 the soot from industrial pollution turned tree bark dark, now
other culture.
making dark colored moths the more camouflaged (bottom picture). In
1850 the frequency of dark moths was 2%; by 1900 it was 95%. The
The topography of language is more complex.
environment had changed and the “selection pressures” on the moths
Humans have an innate drive to acquire speech. Unchanged correspondingly.
like other primates they babble, invent words, and experiment with meaning. This "first language" is
universal in humans across culture, and indicates that the "upper slope" of the topography of language is well
defined, though the lower slope of "second language" (i.e. one's native tongue) is broad and ill-defined, shifting
with culture.
Genetic studies based on the comparison of identical and fraternal twins suggest that primary mental abilities and perceptual and motor skills are the most influenced by heredity, while personality traits are the least influenced. It seems that abilities needed to cope with relatively unvarying
problems in the physical environment develop along narrow channels,
while the qualities of personality, which represent adjustments to the rapidly shifting social environment, are more malleable. Actions that must
be induced rapidly are guided by emotion, for example childhood phobias, fears of snakes, spiders, rats, heights, dislike of different tastes.
These were all potentially dangerous in our ancient environment. Not so
modern dangers, of which children have no inherent fear, such as knives,
guns, and electrical outlets. In early human history fears and phobias
might have provided an extra margin of security needed to ensure survival.
If humans evolved according to evolutionary laws, then even the human propensity to create ritual, both religious and secular, may well be
in response to biological messages. Similarly, the universal human tendency to dichotomize, to classify other human beings into two artificial
categories, kin verses non-kin, members versus non-members, makes
complete sense only in terms of genetic advantage: individuals seek to
perpetuate their own genes (which are carried in relatively large proportion by kin) at the expense of the stranger. Intraspecific competition
(competition within a species) is a basic tenet of evolutionary theory.
The key to many aspects of human culture is hypertrophy, the exagA prehistoric human skull was found in a cave
with holes in the cranium. The holes matched
gerated growth of pre-existing structures, the basic social responses of
perfectly with the canines of a leopard, which
the hunter-gatherers have metamorphosed from relatively modest envihad apparently dragged the body into the cave
ronmental adaptations into elaborate, sometimes monstrous forms in
before consuming it. Life life has always been
perilous for Homo sapiens.
more advanced societies. Nationalism and racism, for example, are the
culturally nurtured outgrowths of simple tribalism. Within the Kung
tribe in Africa, the Nyae Nyae Kung speak of themselves as perfect and clean, and other Kung people as alien
murderers who use deadly poisons. More developed civilizations have raised this mechanism of self aggrandizement to an art form, exalting themselves by divine sanction and denigrating others with false histories.
Often the origins of these cultural elaborations are hidden. For example, anthropologist Marvin Harris has
suggested that chronic meat shortage may be the underlying mechanism in the evolution of certain religious beliefs in some cultures. Ancient Mexico was deficient in large game. Thus as Aztec civilization flourished in the
Valley of Mexico, acquisition of meat protein grew increasingly difficult. When Cortez entered the Aztec capital of Tenochititlan in 1521, he found a hundred thousand skulls stacked in neat rows in the city center. The Aztecs believed that human sacrifice was necessary to please the high gods. In fact immediately after their hearts
had been cut out, the victims were systematically butchered, and their parts distributed and eaten. Genetic coding for quality protein had given rise to elaborate religious ritual, serving largely to conceal the cannibalism adopted to fulfill the genetic imperative for protein. Biologically determined behavior pervades all aspects of
human life. In what follows, four areas of human behavior will be investigated for biological roots; aggression,
sexuality, religion, and learning.
Aggression
Are human beings innately aggressive? From a survey of history one would have to conclude that we are.
Warfare, organized aggression, has been endemic throughout history. And virtually all societies have invented
elaborate sanctions and laws designed to minimize internal and authorize external conflict. In an effort to exonerate the genes, some point to the tiny
minority of societies that appear to be
nearly or entirely pacific. But innateness refers to the measurable probability that a trait will develop, not to the
certainty that the trait will develop in
all environments.
Most kinds of aggressive behavior
among members of the same species
are responses to crowding in the environment. Animals use aggression as a
technique for gaining control over necessities that are scarce. As the population grows denser, aggression
increases. Some species seldom or never run short of the basic necessities of
life. Such animals are typically pacific
toward each other. If aggression conA cartoon making fun of the human proclivity towards aggressiveness: the two armies
fers no advantage, it is unlikely to be
are fighting over the spelling of catsup.
encoded into innate behavior.
Humans, while markedly predisposed towards aggression, are not the most violent animal. Recent studies of
hyenas, lions, and langur monkeys have shown that individuals engage in lethal fighting, infanticide, and even
cannibalism at a rate far above that of humans. Alongside of ants, which conduct assassinations, skirmishes and
pitched battles on their way to work, men are all but tranquillized pacifists.
Aggression in humans is not an inborn drive that grows inexorably toward discharge; rather it is an interaction of genetic potential and learning. For example, it has been found in one study of ten warlike and ten pacifist societies that the practice of war is accompanied by a greater development of combatant sports and other
lesser forms of violent aggression.
Many organisms exhibit territoriality, the defense of a defined area of land or space. Territories seem to
contain an almost invincible center: the resident animal defends the territory far more vigorously than intruders
attempt to usurp it, and thus the defender usually wins. It has in a sense a moral advantage over trespassers.
The biological formula of territorialism translates easily into territorial practices of human societies. It has
been shown that areas defended by hunter-gatherers are just those that appear to be the most economically defensible. The Western Shoshoni of the Great Basin, whose resource-poor land was too vast to defend, had no
concept of ownership of land. In contrast the Owens Valley Paiute occupied fertile land in areas of abundant
game, the valley was finely divided into resource units, each owned by a different band. These territories were
defended by means of social and religious sanctions and occasional threats and attacks.
The force behind most warlike policies is ethnocentrism, the irrationally exaggerated allegiance of individuals to their kin and fellow tribesmen. This powerful drive to favor one's own social group—which in ancient
times was always one's kin group—makes complete sense in terms of evolutionary theory, in which selection
for kin's genes (which are closely related to one's own) may augment or even supplant selection for one's own
genes. Thus modern man walks in the shadow of primitive man, dividing the world into two tangible parts, the
near environment of home, kin, nation-state, and the more distant universe of outside villages, wild animals and
enemies.
The cultural evolution of aggression appears to be guided by three forces, 1) genetic predisposition toward
learning some form of group aggression, 2) the necessities imposed by the environment, and 3) the previous history of the group, which biases toward the adoption of particular modes of behavior. To use the landscape metaphor, the channels of societal aggression are deep, a society is not likely to avoid them altogether. A given
society is influenced to take a particular direction by the physical and cultural realities in which it exists.
There is some evidence that culturally entrenched warfare can be reversed. In pre-European times the Maori
of New Zealand were among the most aggressive people on earth. Insults, hostility and retribution were carefully tallied by the 40-odd tribes, and victory by force of arms was the highest achievement. The introduction of
European weapons lead to an escalating arms race, but the price paid even by the victors proved unbearable. By
1830 the dominant tribe had begun to question the use of fighting for revenge; the old values crumbled soon afterward.
In our own time, societies have come within one step of nuclear annihilation. Yet when countries have
reached the brink, for example during the Cuban Missile Crisis, the leaders have been able to turn back. In the
words of one observer, men use reason as a last resort.
In summary, it can be said that human beings are strongly predisposed to respond with unreasoning hostility
to external threats, and to escalate this hostility to overwhelm the source of the threat by a wide margin of safety. We seem to be programmed to partition other people into friends and aliens, in the same sense that birds are
inclined to learn territorial songs. These rules are most likely to have developed over the millions of years of
human evolution, and have thus conferred a biological advantage on those who conformed to them most fully.
The rules of aggression are largely obsolete. We are no longer hunter-gatherers who settle disputes with
spears and arrows. But to acknowledge the obsolescence of the rules is not to banish them. It does though, give
rise to the possibility of consciously choosing to learn and teach other modes of behavior, to leave group aggression lie at rest, latent and unsummoned.
Sex
Sex is not designed primarily for reproduction: evolution has devised much more efficient ways for creatures to multiply than the complicated procedures of mating and fertilization. Bacteria simply divide in two,
fungi shed immense numbers of spores, and hydras bud offspring directly from their trunks. I n humans a swift
bacterium-like method of asexual reproduction occurs on those rare occasions when identical twins are created
by a single division of an already fertilized egg.
Nor is the primary function of sex the giving and receiving of pleasure. The vast majority of animal species
perform the sexual act mechanically and with minimal foreplay. Bacteria and protozoans form sexual unions
without the benefit of a nervous system. Many invertebrates simply
shed their sex cells into the surrounding water, there to meet gametes
of the opposite sex. Pleasure seems to be a device for animals that
copulate, a means to induce the investment of time and energy required in courtship, sexual intercourse and parenting.
Sex is risky, and is consumptive of time and energy. Reproductive organs of humans are complex and subject to lethal malfunctions
at both the gene and higher levels (for example venereal disease, and
ectopic pregnancies).
Thus sex by itself does not offer a selective advantage. In fact, it
imposes a genetic deficit, in that a sexually reproducing organism
passes only one half of its genes to its offspring, whereas an asexually reproducing organism produces offspring identical to itself.
The ultimate, evolutionary raison d'etre of sex has grown more
mysterious in recent years. Until recently biologists believed sex
speeded up the rate of evolution, so that over long periods of time
sexual species replaced asexual by virtue of their more rapid evolutionary response to environmental change. A growing appreciation
of the disadvantages of sex (as mentioned above) has made this
equation questionable, and caused biologists to seek further for an
evolutionary cause. It may be a response to predation and parasitism,
a form of rapid evasive response to prey strategies.
Our 46 human chromosomes come in pairs (top
circle), one from the mother and one from the
Why are there just two sexes? It is theoretically possible to create
father. When sex cells are are produced, each
a
sexual
system based on one sex, that is to say, on uniform individupaired set sorts independently of the others;
als who produce identical reproductive cells. Some lower plants do
the possible ways to recombine these 46
chromosomes totals 64 trillion.
just that. It is also possible to have hundreds of sexes, which is the
mode among some fungi. But a two sex system prevails. This system appears to permit the most efficient possible division of labor.
The female is specialized for making eggs. The large size of the egg enables it to resist drying, to survive
adverse periods by consuming stored yolk, and to divide a few times after fertilization before needing to take in
nutrients from the outside. The male sperm is a stripped down cellular unit, with a head packed with DNA and a
tail with just enough energy to carry the vehicle to the egg.
The difference in size between the two kinds of sex cells is often extreme. The human egg is 85,000 times
larger than the human sperm. The consequences of this gametic dimorphism resound throughout the biology
and psychology of human sex. The most important immediate result is that the female places a greater investment in each of her sex cells. A woman can expect to produce only about 400 eggs in her lifetime. Of these a
maximum of about twenty can be converted into healthy infants. The costs of bringing an infant to term and
caring for it afterward are enormous. In contrast, a man releases 100 million sperm with each ejaculation, each
one capable of fertilizing an egg. Once the male has achieved fertilization, his purely physical commitment has
ended. His genes will benefit equally with those of the female, but his investment will be far less than hers unless she can induce him to contribute to the care of the offspring. If a man were given total freedom to reproduce, he could theoretically inseminate thousands of women in his lifetime.
The resulting conflict of interest between the sexes is a property of not only human beings, but also the majority of animal species. Males are characteristically aggressive, especially toward one another and most intensely during breeding season. One male can fertilize many females, but a female can be fertilized by only one
male. Thus it pays males to be aggressive, hasty, fickle, and undiscriminating. In theory it is more profitable
for females to be coy, to hold back until they can identify the male with the 'best' genes. In species that rear
young, it is also important for the female to select males who are more likely to stay with them after insemination.
Although humans display considerable plasticity in their cultural norms for sex roles, at a deeper level they
are faithful to this biological reality. Humans tend to be mildly polygynous: about 3/4 of all human societies
permit the taking of multiple wives. In contrast, marriage to multiple husbands is sanctioned in less that one
percent of societies. The remaining monogamous societies often have extramarital strategies that approach polygyny.
The sexual division of labor is reflected in anatomy. Men are on the average 20-30% heavier than women.
They are stronger and quicker in most categories of sport. They are particularly suited for running and throwing, the specialties of the ancestral hunter-gatherer males. Women surpass men in sports that are the furthest
removed from archaic hunting and aggression, like long-distance swimming and acrobatic (but not strength)
gymnastics.
The average temperamental difference between the human sexes are also consistent with the generalities of
sexual reproduction. Women as a group are less assertive and less physically aggressive. The magnitude of the
distinction depends on the culture. The physical and temperamental differences between men and women have
been expressed in culture in universal male dominance. There is not a single society recorded in which women
have controlled the political and economic lives of men. Even when queens and empresses rule, their intermediaries are primarily men. In about 75% of societies studied lineage is reckoned through the male line.
There is substantial evidence that there are behavior differences between male and female that are genetically determined. In general, girls tend to be more
intimately sociable and less physically venturesome.
From the time of birth, for example, they smile more
than boys. Several independent studies have shown
that newborn females respond more frequently than
males with eyes-closed, reflexive smiling. The habit is
soon replaced by deliberate, communicative smiling
that persists into the second year of life. Frequent smiling then becomes one of the more persistent of female
traits and endures through adolescence and maturity.
By the age of six months, girls also pay closer attention
to the sights and sounds used in communication than
they do to non-social stimuli. Boys of the same age
make no such distinction.
Sexuality and aggression are related, as this cartoonist conveys.
The nuclear family can also be measured by the
insights of sociobiology. The traditional strength of the nuclear family is currently weakening in the west: the
divorce rate in the United States is approaching 50%, as is the number of single parent families. Nonetheless, a
set of closely relating adults with their children remains one of the universals of human social organization.
Even in societies that attempt to break the rule, like the Israeli kibbutzes, the family unit remains emotionally
intact within the larger structure of the group. The human predisposition to organize in families even asserts
itself in women's prisons, where it has been found that inmates commonly organize themselves into family-like
units centered on a sexually active pair. Interestingly, the inmates of men's prisons do not
organize into families, but into hierarchies and castes, in which dominance and rank are paramount.
Because of the large investment of time and energy involved in child-rearing, it is to the advantage of each
woman in the hunter gatherer societies to secure the allegiance of men who will contribute to the process. It is
also to the advantage of each man to obtain exclusive sexual rights to a woman to be sure he is investing his
time in the replication of his genes. This exchange has resulted in the near universality of the pair bond.
Human beings are unique among the primates in the intensity and variety of their sexual activity. Among
other higher mammals, humans are matched in their sexual activism only by lions and bonabo chimpanzees.
The external sex organs of both men and women are exceptionally large, and are advertised by tufts of pubic
hair. The breasts of women are enlarged beyond the size required to house the mammary glands, while the nipples are erotically sensitive and encircled by conspicuously colored areolas. In both sexes the ear lobes are
fleshy and sensitive to the touch.
Women are most unusual among mammals in lacking the estrus, or period of heat. The females of most
other primate species become sexually active only at the time of ovulation. In women the period of ovulation is
hidden, so much so that it is difficult in initiate pregnancies or to avoid them even when the time of insemination
is carefully selected. Women remain sexually receptive, with little variation, throughout the menstrual cycle.
Why has sexual responsiveness become nearly continuous? The most plausible explanation is that the trait
facilitates bonding. Frequent sexual activity between male and female conferred a sexual advantage by more
tightly joining the members of primitive human clans. It served as a principle device in cementing the pair
bond, and thus ensuring adequate care for offspring. It also reduces aggression among the males. In baboon
troops and other non-human primate societies male hostility is intensified when females come into heat. Removing estrus in early human beings reduced the potential for such competition and safeguarded the alliances of
males.
Human beings are connoisseurs of sexual pleasure. From casual inspection of potential partners, through
fantasy and foreplay to coition, humans devote a remarkable amount of time to sexuality. This "extended foreplay" has little to do with reproduction; it probably has everything to do with bonding. If insemination were the
only biological function of sex, it could be achieved far more economically and safely in a few seconds of
mounting and insertion. The least social of mammals mate in just this way. The species that have evolved longterm bonds are also, by and large, the ones that rely on elaborate courtship rituals. It is consistent with this trend
that most of the pleasures of human sex serve as reinforcers to facilitate bonding.
Religion
The proclivity toward religious belief is one of the most powerful forces in the human mind. Anthropologist Anthony Wallace estimates that mankind has produced on the order of 100,000 religions in the past 50,000
years. It was predicted by many that science and learning would erode the foundations of religion, but this has
not proven to be the case. To take but one example, the United States, technologically and scientifically perhaps
the most advanced nation in history, is also the second most religious, after India. Our schizophrenic society is
build upon scientific knowledge but seems to survive on inspiration derived from the very beliefs which that
knowledge erodes.
Can religious practices be mapped by genetic advantage and evolutionary change? It is clear that the practices of any religion must ultimately meet the demands of the environment. If religions weaken their societies
during warfare, encourage the destruction of the environment, shorten lives or interfere with reproduction they
will, regardless of their short-term emotional benefits, initiate their own decline. Religious practices that enhance survival and reproduction of the practitioners will favor the genes that prescribe the controls that initiate
and perpetuate the practices.
The Shakers are a case in point. They were a Christian sect of 19th century America that practiced celibacy.
The sect grew at a meteoric rate for a time—they were
able to override the rules of natural selection
temporarily—but they soon faded from existence, due
to their failure to enhance their own reproductive fitness.
The sacred rites of primitive societies have effects
that appear to be directly and biologically advantageous. Ceremonies can offer information on the
strength and wealth of tribes and families. Among the
Maring of New Guinea, there are no chiefs or other
leaders who command allegiance during war. A group
gives a ritual dance, and individual men indicate their
willingness to lend military support by whether they
attend the dance or not. In more advanced societies
military parades may be an extension of the same code.
A map of the major religions of the world; we are not concerned here
with what those religions are, but rather in observing the fact that peoThe famous potlatch ceremonies of the Northwest
ple have a strong tendency to adopt religions beliefs all over the world.
Coast Indians enable individuals to advertise their
wealth by the amount of goods they give away, just as peacock advertises its genetic fitness by displaying the
quality and quantity of its tail. Both Indian and bird may in so doing enhance their own fitness.
Rituals regularize relationships in which there would otherwise be ambiguity and wasteful imprecision. The
best examples of this mode of communication are rites of passage. The maturation of a boy from child to man is
a very gradual process. The rite of passage eliminates this ambiguity by arbitrarily changing the classification
from a continuous gradient into a dichotomy. It also serves to cement the ties of the young person to the adult
group that accepts him.
Sacred ritual can be seen to offer a selective advantage to both the individual and the group. It binds individuals together in a powerful bond of allegiance that enhances the fitness of each individual relative to individuals not similarly bonded—because the bond group can respond more successfully to the challenges of the
environment.
The sacred ritual also creates a social hierarchy of priest/leader and followers. This willing subordination to
a leader can again lend Darwinian advantage to all involved. The plasticity of human social behavior is both
strength and a danger. If each individual or family worked out its own rules of behavior, society as a whole
would disintegrate into chaos. For societies to exist they must codify behavior; sacred ritual performs this task
admirably. The ability of individuals to conform permits them to enjoy the benefits of membership with a minimum of energy expenditure and risk. Although the rivals of the conformists in the society may gain a momentary advantage through selfishness and irreverence, it is lost in the long run through ostracism and repression.
The summed efforts of the group give the average member abundant returns:
"The LORD spoke to Moses and said, 'Count all that has been captured, man or beast, you and Eleazar the
priest and the heads of families in the community, and divide it equally between the fighting men who went on
the campaign and the whole community.' " (Num. 30:25-38)
One has to extrapolate primitive ritual and dogma quite a distance to arrive at the elaborate ritual of modern
day religions. Nonetheless, the similarities are evident, and the potential for rituals of varying degrees of complexity to inspire a fierce emotional loyalty to the group.
As with insights into other aspects of human behavior that have some biological basis, one may well ask, so
what? It is unlikely that humans will cease to be aggressive or cease to be attracted to religiousity even after
acknowledging a biological basis. The answer may lie in the unique capacity that humans have to learn and
adopt new behaviors. This ability to learn may allow us to override genetic messages which have in fact become detrimental to individual fitness—and individual fitness long ago became tied to the well being of the
larger group in human society.
Learning
Classical learning theory suggests that by trial and error a given animal can learn to respond to a wide variety of stimuli. This suggests a certain plasticity to the learning process which may in fact often not exist. It has
been shown for example that a rat can easily learn to associate the taste of a food to a sensation of nausea; he
can quickly learn to associate food size to physical pain, but he cannot make the inverse associations, that is, he
fails to associate food taste to physical pain (when such an association experimentally existed) and food size
with nausea. This is likely due to the fact that an animal can get sick in nature from eating tainted food, while
food size is rarely a threat. Similarly, size of objects is an indication of physical threat, but not of palatability.
The rats learning is specific to its environment.
Insight learning is the ability to perform a correct or appropriate behavior on the first attempt in a situation
with which the animal has no prior experience. If a chimpanzee is placed in an area with a banana hung too
high above its head to be reached, and several boxes on the floor, the chimp can reflect cognitively on the situation and then stack the boxes to allow it to reach the food. In general, insight is best developed in primates and
other mammals; even in these groups the amount of insight often varies substantially from one situation or species to another.
Consciousness can be thought of as an extension of insight learning. Consciousness is a system by which
we are in some sense aware of ourselves and our relationship to others and the rest of the world. For this reason
it has likely evolved in the context of success in social matters. It is clear that how others see us is absolutely
crucial to social success. Consciousness may be a system for testing the question of how others see us and
adjusting our image in our own self-interest.
A central aspect of consciousness is the ability to
look ahead, the capability that we call "foresight." it is
the ability to plan, and in social terms the ability to outline a scenario of what is likely going to happen, or
what might happen, in social interactions that have not
yet taken place. Thus it is a system whereby we improve our chances of doing those things that will represent our own best interests.
In the course of using our consciousness and foresight to build scenarios and plan our social interactions,
we visualize alternatives and test them one by one. We
Chimpanzees are capable of insight learning: reviewing possibilities
see these different alternatives as available to us if we
and scenarios inside the brain and then acting on them. One famous
example from experimentation is chimps stacking boxes in order to
choose to use them. Our ability to visualize alternareach a banana.
tives, particularly in connection with social interactions, may be the basis for the concept of free will. In this sense, free will is not incompatible with the idea of
an evolved tendency to maximize inclusive fitness.
The plasticity of human behavior and the specie’s
unprecedented ability to learn new behaviors suggests
we can to some degree choose modes of existence that
are adaptive and functional in rapidly changing environments. This is certainly the present human condition,
evolving rapidly, as we have, from hunter-gatherers to
densely populated urban dwellers, from spear-throwers
to missile launchers. We are more controlled by our
genes than we have realized (a reasonable assertion,
given that we were unaware of the existence of genes
until a few decades ago),and so it would seem that the
more we discover about the mechanisms of genetic control, the more possible it will become to transcend these
controls through awareness and conscious choice. We
may then in the words of A. Rosenfeld, "for the first
time in our history, work for ourselves instead of for our
genes, exercise truly free will and free choice, give free
Humans were hunter-gatherers for 98% of the 300,000 years
rein to our minds and spirits, attain something close to
that the species has existed.
our full humanhood.''