How large were these communities? Most modern hunter-gatherer groups range in size from 50 to 400 residents, with a medium range of 100 to 200 people. Anthropologist Napoleon Chagnon, in his extensive studies of the Yanomamö people in the Amazon, found the typical group to be roughly 100 people in size, with 40 to 80 living together in the rugged mountain regions, and 300 to 400 members living together in the largest lowland villages. He has also noted that when groups get excessively large for the carrying capacity of their local environment (given their level of technology), they fission into smaller groups. Such bifurcations may also be a product of exceeding the carrying capacity of the social environment. Psychologist Robin Dunbar, in his book, Grooming, Gossip and the Evolution of Language, argues that the figure of 150 people in a typical group has a deeper evolutionary basis. It turns out that 150 is roughly the number of living descendants (wives, husbands, and children) a Paleolithic couple would produce in four generations at the birthrate of hunter-gatherer peoples—this is how many people they knew in their immediate and extended family. Archaeologists believe that early agricultural communities in the Near East 7,000 years ago typically numbered about 150 people. Even modern farming communities, like the Hutterites in Europe (and now Dakota and Canada), average about 150 people.
When groups get large they split into smaller groups. Why? According to the Hutterites, it is because shunning does not work as well in large groups, and shunning is a primary means of social control. Sociologists know that once groups exceed 200 people a hierarchical structure is needed to enforce the rules of cooperation and to deal with offenders, who in the smaller group could be dealt with through informal personal contracts and social pressure. Still larger groups need chiefs and a police force, and rule enforcement involves more violence or the threat of violence. Even in the modern world with a population of six billion people crowded into dense cities, people find themselves divided into small groups. In the Second World War, for example, the average size company in the British army was 130 men, in the United States army it was 223 men. The 150 average also fits for the size of small businesses, of departments in large corporations, and of efficiently run factories. A Church of England study, conducted in an attempt to balance the financial support provided by a large group and the intimacy of a small group, concluded that the ideal size for congregations was 200 or less. The average number of people in any given person’s address book also turns out to be about 150 people.
It would appear that 150 is the number of people each of us knows fairly well. Dunbar claims that this figure fits a ratio of primate group size to their neocortex ratio: that is, the volume of the neocortex—evolutionarily the most recent regions of the cerebral cortex—to the rest of the brain. Extremely social primates need big brains to handle living in big groups, because there is a minimum amount of brain power needed to keep track of the complex relationships, in order to live in relative peaceful cooperation. Dunbar concludes that these groupings “are a consequence of the fact that the human brain cannot sustain more than a certain number of relationships of a given strength at any one time. The figure of 150 seems to represent the maximum number of individuals with whom we can have a genuine social relationship, the kind of relationship that goes with knowing who they are and how they relate to us. Putting it another way, it’s the number of people you would not feel embarrassed about joining uninvited for a drink if you happened to bump into them in a bar.”
Morality most likely evolved in these tiny bands of 100 to 200 people as a form of reciprocal altruism, or I’ll scratch your back if you’ll scratch mine. But as Lincoln noted, men are not angels. There are cheaters. Individuals defect from social contracts. Reciprocal altruism, in the long run, only works when you know who will cooperate and who will defect. In these small groups, cooperation is regulated through a complex feedback loop of communication among members of the community. (This also helps to explain why people in big cities can get away with being rude, inconsiderate, and uncooperative—they are anonymous and thus not subject to the normal checks and balances that come with seeing the same people every day.) In order to play the game of reciprocation you need to know whose back needs scratching and who you will trust to scratch yours. This information is gathered through telling stories about other people, better known as gossip. From an anthropologist’s perspective, gossip is a tool of social control through communicating cultural norms, as Jerome Barkow observed: “Reputation is determined by gossip, and the casual conversations of others affect one’s relative standing and one’s acceptability as a mate or as a partner in social exchange. In Euro-American society, gossiping may at times be publicly disvalued and disowned, but it remains a favorite pastime, as it no doubt is in all human societies.”
The etymology of the word gossip, in fact, is enlightening. The root stem is godsib, or god and sib, and meant “akin or related.” Its early use, as traced through the Oxford English Dictionary, included “one who has contracted spiritual affinity with another,” “a godfather or godmother,” “a sponsor,” and “applied to a woman’s female friends invited to be present at a birth” (where they would gossip). (In one of its earliest uses in 1386, for example, Chaucer wrote: “A womman may in no lasse synne assemblen with hire godsib, than with hire owene flesshly brother.”) The word then mutated into talk surrounding those who are akin or related to us, and eventually to “one who delights in idle talk,” as we employ it today. Not surprisingly, we are especially interested in gossiping about the activities of others that most affect our inclusive fitness. that is, our reproductive success, the reproductive success of our relatives, and the reciprocation of those around us. Normal gossip is about relatives, close friends, and those in our immediate sphere of influence in the community, plus members of the community or society who are high ranking or have high social status. It is here where we find our favorite subjects of gossip—sex, generosity, cheating, aggression, violence, social status and standings, births and deaths, political and religious commitments, physical and psychological health, and the various nuances of human relations, particularly friendships and alliances. Gossip is the stuff of which not only soap operas but also grand operas are made. But why, in our culture, do we gossip about total strangers, namely celebrities? The probable reason is that the mass media make these figures so familiar to us that they seem like relatives, friends, and members of our community. Why would anyone care with whom Princess Diana slept or what her status was in the royal family? Because our Pleistocene brains are being tricked into thinking that Princess Diana is someone we personally know and care about.
FROM MORALITY TO RELIGION
What has all this to do with religion? Religion is a social institution that evolved as an integral mechanism of human culture to create and promote myths, to encourage altruism and reciprocal altruism, and to reveal the level of commitment to cooperate and reciprocate among members of the community. That is to say, religion evolved as the social structure that enforced the rules of human interactions before there were such institutions as the state or such concepts as laws and rights. We would do well to remember that the history of the modern nation-state with constitutional rights and protection of basic human freedoms can be measured in mere centuries, whereas humans evolved as social primates over the course of millions of years, and human culture itself dates back at least 35,000 years, if not more. The principal social institution available to facilitate cooperation and goodwill was probably religion. An organized establishment with rules and morals, with a hierarchical structure so necessary for social primates, and with a higher power to enforce the rules and punish their transgressors, religion evolved as the penultimate effort of these pattern-seeking, storytelling, mythmaking animals. How and why did it evolve?
At the most fundamental level, blood is thicker than water, and Richard Dawkins’ famous selfish-gene model accounts for altruism and cooperation among families and extended families. That is, the percentage of genes shared among various degrees of ki
nship will predict the amount of benefits we receive from a given relative (on average—families will vary, of course). Thus, we do not need religion and gods to enforce the rules in the immediate family where the ties are close. Most parents do just fine. But when we move out from the circle of extended families and into the community and society, we need other mechanisms to ensure that people are kind to one another.
Morality evolved over eons in the paleolithic environment where individuals cooperated and competed with one another to meet their needs. Individuals belonged to families, families to extended families, extended families to communities, and, in the last couple of centuries, communities to societies. This natural progression, which is now in its latest evolutionary stages of perceiving societies as part of the species, and the species as part of the biosphere, is illustrated in the Bio-Cultural Pyramid below.
The lower strata of the Bio-Cultural Pyramid depict the 1.5 million years over which our moral behavior evolved under primarily biogenetic control, and the middle layer the transition about 35,000 years ago when sociocultural factors increasingly assumed control in shaping our ethical precepts. Obviously this was a continuous process. There was no point at which an Upper Paleolithic Moses descended from a glacier-covered mountain to present The Law to his fellow Cro-Magnons.
The Bio-Cultural Pyramid: A model of the origin and development of ethical behavior.
Nevertheless, the semipermeable bio-cultural transitional boundary divides time and dominant source of influence, where the individual, family, extended family, and paleolithic communities were primarily molded by natural selection; whereas neolithic communities and modern societies were and are primarily shaped by cultural selection. Starting at the bottom of the Bio-Cultural Pyramid, the individual’s need for survival and genetic propagation (through food, drink, safety, and sex) is met by way of the family, extended family, and the community. The nuclear family, however, is the foundation. Despite assaults on it in the second half of the twentieth century, the family remains the most common social unit around the world. Even within extremes of cultural deprivation—slavery, prisons, communes—the two-parents-with-children structure emerges: (1) African slave families broken up retained their attachment and structure for generations through the oral tradition; (2) in women’s prisons pseudofamilies self-organize, with a sexually active couple acting as “husband” and “wife” and others playing “brothers” and “sisters”; (3) even when communal collective parenting is the norm (e.g., Kibbutzim), many mothers switch to the two-parent arrangement and the raising of their own offspring. For this foundational social structure our evolutionary history is too strong to overcome. Conservatives need not bemoan the decline of families. They will be around as long as the species continues.
Moving up the Bio-Cultural Pyramid, basic psychological and social needs such as security, bonding, socialization, affiliation, acceptance, and affection evolved as mental programs to aid and reinforce cooperation and altruism, all of which facilitate genetic propagation through children. Kin altruism works indirectly—siblings and half-siblings, grand- and great-grandchildren, cousins and half-cousins, nieces and nephews, all carry portions of our genes. This is what is known as inclusive fitness, and applies to anyone who is genetically related to us. In larger communities and societies, where there is no genetic relationship, reciprocal altruism (if you scratch my back I will scratch yours) and indirect altruism (if you scratch my back now I will scratch yours later) supplements kin altruism. Inclusive fitness gives way to what we might call exclusive fitness. The natural progression of exclusive fitness may be the adoption of species altruism and bioaltruism (we will prevent extinction and destruction now for a long-term payoff), which Wilson argues in Biophilia may even have a genetic basis. But, Wilson confesses, this should probably still be grounded in self-interest arguments—my children and grandchildren will be better off in a future with abundant biodiversity and a healthy biosphere—since inclusive fitness is more powerful than exclusive fitness.
The width of the Bio-Cultural Pyramid at any point indicates the strength of ethical sentiment, and the degree to which it is under evolutionary control. The height of the pyramid at any point indicates the degree to which that ethical sentiment extends beyond our own genomes (ourselves). But the pyramid also shows that these two sets of sentiments are inversely related. The further a sentiment reaches beyond ourselves, the further it goes in the direction of helping someone genetically less related, and the less support it receives from underlying evolutionary mechanisms.
New research by philosopher Elliott Sober and biologist David Sloane Wilson, presented in their 1998 book Unto Others: The Evolution and Psychology of Unselfish Behavior, indicates that there may have been an additional selection component in human evolution that gave rise to cooperation and altruism, and that is a modified version of group selection. This is a volatile subject among evolutionary theorists because for the past thirty years, group selection has been next to creationism as the doctrine strict Darwinians most love to hate. From George Williams’s 1966 book Adaptation and Natural Selection to Richard Alexander’s 1987 book The Biology of Moral Systems to Richard Dawkins’s several books throughout the 1990s, group selection was vilified as the pap of bleeding-heart liberals who couldn’t deal with the reality of “nature red in tooth and claw.” Michael Ghiselin’s 1974 description summed up the Darwinian literalists perspective, especially the last line:
The economy of nature is competitive from beginning to end … . The impulses that lead one animal to sacrifice himself for another turn out to have their ultimate rationale in gaining advantage over a third … . Where it is in his own interest, every organism may reasonably be expected to aid his fellows … . Yet given a full chance to act in his own interest, nothing but expediency will restrain him from brutalizing, from maiming, from murdering—his brother, his mate, his parent, or his child. Scratch an “altruist,” and watch a “hypocrite” bleed.
Sober and Wilson, through a sophisticated mathematical model and series of logical arguments, and defining a group as “a set of individuals that influence each other’s fitness with respect to a certain trait but not the fitness of those outside the group,” demonstrate that “natural selection can operate at more than one level of the biological hierarchy.” They show how “individual selection favors traits that maximize relative fitness within single groups,” and that “group selection favors traits that maximize the relative fitness of groups.” Of course, “altruism is maladaptive with respect to individual selection but adaptive with respect to group selection.” Therefore, they conclude, “altruism can evolve if the process of group selection is sufficiently strong.” For example, they cite William Hamilton’s analysis of how consciousness might have provided a group selective advantage for certain human populations with regard to the ethical enforcement of rules: “Consider also the selective value of having a conscience. The more consciences are lacking in a group as a whole, the more energy the group will need to divert to enforcing otherwise tacit rules or else face dissolution. Thus considering one step (individual vs. group) in a hierarchical population structure, having a conscience is an ‘altruistic’ character.”
Part of the problem in this debate is in how certain terms are defined, such as altruism and cooperation, and the tendency to force these categories into either-or choices for human actions. Humans are either altruistic or selfish. Humans are either cooperative or competitive. But altruistic and cooperative are not reified things, they are behaviors. And like all behaviors, there is a broad range of expression, from a little to a lot. Applying fuzzy logic can help clarify this complex human phenomenon, where we might assign fuzzy numbers to altruism or cooperation. Depending on the circumstances, someone might be, say, .2 altruistic and .8 nonaltruistic (or selfish), or .6 cooperative and .4 noncooperative (or competitive). Humans can be both altruistic and nonaltruistic, cooperative and noncooperative.
One problem with reciprocal altruism is this: How do I k
now that if I scratch your back you will scratch mine? I am more than willing to cooperate with unrelated members of my community, but only if I am reasonably certain that they are going to reciprocate. How can I find out who are the cooperators and who are the defectors? Gossip is one way. Past experience with my fellow community members is another. Combined, these give me enough information to make a decision (even if it is on an unconscious level) about whom I can trust.
In a way, daily life can be modeled by a game theory technique called the Prisoner’s Dilemma. Two individuals who cooperated in committing a crime are caught, arrested, and offered the chance of a reduced sentence if one will rat out the other. The district attorney can convict both of them of a minor offense, but if one of them confesses, he can go free while the other rots in jail with a long sentence. What will they do? It depends on their respective reputations for being trustworthy. Let us simplify the game where each player gets one point if both cooperate, either one can get two points by defecting when the other cooperates, and zero points if both defect. When only one round of the game is played, most people defect. But when the game is iterated, or repeated for numerous rounds with the same players, cooperation is the norm. When you learn that your partner is a cooperator and not a defector, you become a cooperator yourself.
How We Believe, 2nd Ed. Page 23