SOCIAL BEHAVIOR AND SACRIFICE

Traditions are Not (Ex= plained by) “r”

Lyle Steadm= an

Department = of Anthropology

Arizona State University

Human Behav= ior and Evolution Society Meeting

Santa Barbara, California

June, 1995<= /p>

At the time Darwin’s theory became popular, survival became the measure of success of a trait, epitomized in the phrase, “survival of the fittest.”&nbs= p; Although survival remains popular as an explanation, since the emerg= ence of sociobiology that measure of success has been changed to reproduction—“reproductive success.” Given our focus on humans and their intensive K-strategy [or care strategy as opposed to a reproducti= ve or “r” strategy], it is time now to extend that measurement of success beyond reproduction or even [the counting of numbers of] grandchild= ren, to more distant descendants.

&nbs= p; Everyone here assumes that we cannot acc= ount for human culture without the use somehow of natural selection. The problem is how to do it. Although anthropologists have not = come up with a clear definition of culture, they assume it to be a product of a social group. It is time we r= ealize explicitly that this focus on culture as a product of a social group has led sociobiologists astray, away from an understanding of how culture has been selected for. It is crucial t= hat we realize that culture is not a product of a social group, but of individuals. Its source is individuals, not groups. As a highly stable, inheritable phenotype, cultural behavior has been selected for. The human transmission of culture from ancestor to descendant, as traditions, is an extreme K-strategy, and strongly influences an individual’s suc= cess in leaving descendants. The s= uccess of a K-strategy cannot be measured by counting children or grandchildren, f= or it [the K-strategy] is at the expense of reproduction.

&nbs= p; Recognition of two facts, combined with the use of Darwinian natural selection, should = lead to a significant increase in our knowledge of human behavior. The first fact: during the last se= veral million years there has been a powerful selection for the transmission of traditions from ancestor to descendant.&nb= sp; Without this massive selection for culture, humans would be little different from chimpanzees, with whom they share, apparently, more than ninety-five percent of their genome. Our traditions constitute the accumulated, successful behavior and knowledge of our ancestors, who not only survived and reproduced with that behavior, but left descendants who did the same. It is this massive accumulation th= at distinguishes humans from all other creatures. The second crucial fact is this: a= s a K-strategy, the success of any tradition cannot be measured by the counting= of offspring or grandchildren, but only more distant descendants. The transmission of cultural behav= ior from ancestor to descendant constitutes the most intensive K-strategy ever developed. Such transmission = is not only at the reproductive expense of the parent, but of the descendants as well. Thus, traditions repres= ent not a reproductive, but a descendant leaving, strategy.

&nbs= p; An understanding of culture obviously is central to an understanding of human behavior, even though culture usually is said to be a product of a social group. Yet we actually use th= e term culture to refer to behavior that is learned and copied from another individual, regardless of membership in any group. Culture does not imply cooperation, social behavior, or a social relationship. Behavior can be copied from any individual—for example, an enemy’s behavior can= be copied in order to kill him, or the behavior of prey can be copied, as in mimicking the sound of a bird, in order to attract and shoot it. We can copy the behavior of pigs, birds, dogs, cats, etc., and can travel to France = and learn to say “bon jour.” All this is cultural behavior, but none implies that we are in a gro= up with those copied. Thus, cult= ural behavior does not imply a social group, including whatever is meant by “tribe” or “society” (contra, for example, Alexande= r, 1987:104; and Tooby and Cosmides). The widely used term, “cultural environment,” usually implies some kind of a social group, and is held to be the determinant of cultural behavior. In fact, t= he only environmental factor necessary for the acquisition of cultural behavio= r is the presence of another individual of almost any species. For one to behave culturally, what= is necessary is the ability (including having the right genes) to experience t= he particular action of the other individual, to remember it, and then to copy it. The use of the word “culture” is sometimes used synonymously with “society,” as in “a culture.” But in no soc= iety does everyone exhibit the same cultural behavior. In the modern world people in diff= erent societies have copied massively from one another in almost every aspect of life—economics, politics, architecture, technology, religion, pornography, science (like us here), and so on. What does it mean to say the copie= rs are, or are not, members of the same social group as the copied? This copying of people in other so= cial groups has occurred in tribal societies since time immemorial.

&nbs= p; Why have anthropologists not come up with an unequivocal definition of culture? Why has culture not = been defined explicitly according to the way anthropologists actually use the te= rm? The reason, I suggest, is that the= y want culture to be a product of a social group, but they know it isn’t. The attempt to explain human behavior by an undefined and unidentified social g= roup began with the origin of anthropology.&nbs= p; This can be seen in the writings of all the major theorists in the 1= 9^th century, including Edward Tylor, the so-called “father of anthropology,” who first defined culture explicitly as a product of society. By accepting modern anthropologists insistence that culture is a product of a social group, we = have failed to appreciate the point that culture, in the form of traditions, responds to natural selection.

&nbs= p; Associated with the problem of seeing culture as a product of a social group is a ques= tion that almost no one has bothered to ask: what is meant by a social group? A social group is not a name, or b= eing over six feet tall, for such common features imply no interaction. At the minimum, a social group imp= lies some regular cooperation between its members. The social group’s persisten= ce is another problem: is it the same social group when all its members have been replaced, even though its name remains the same? Is a sporting team or a descent gr= oup the dame now as it was years before, even though all its members have died = or been replaced? The most impor= tant social group for most humans is their family, yet families do not endure; t= hey continually break apart, and new families form out of the pieces of old ones. The most stable social groups, on the other hand, are often the least important—that is, they have the least influence on our lives—like a tribe, county, state, or ethnic group. Social groups a= nd cultural behavior are independent phenomena.

&nbs= p; How, then, does cultural behavior persist, if it is not related to a social group? What is the cause of i= ts persistence? In particular, w= hat is the effect of cultural behavior that leads to its continuation through time? Answering this question= is what I take to be the aim of the sociobiological study of humans.

&nbs= p; Most cultural behavior is transmitted from ancestor to descendant, as tradition. Because today we a= cquire much of our culture from non-kin, as from teachers who are strangers, we sh= ould not be misled into thinking that humans always have. Indeed, in tribal societies, most enduring contact is between close kin. And even in our own societies suppo= rt for public education comes primarily (as voting for school bills shows) from parents with school-age children. Retirement communities, consisting mainly of people without school-a= ge children, almost always vote down any school bill. Even modern education is a parental/ancestral strategy.

The transmission of particu= lar, learned behavior from ancestor to descendant profoundly influences the ancestor’s success in leaving descendants, and thereby the frequency = of the behavior being transmitted. A tradition, like any inheritable phenotype, can, by its effect on the behavi= or of descendants, influence its own frequency in later generations. The evolutionary significance of culture, therefore, is as tradition. A tradition can be a highly stable, inheritable phenotype, influenci= ng its own frequency through time. Indeed, that surely must be how culture itself evolved.

&nbs= p; For humans, a stone axe-making tradition that remained more or less the same for more than a million years presents us with an outstanding example of a tradition that has successfully promoted its own frequency. It became an adaptation, presumabl= y, by enhancing the ability of descendants to hunt and fight, and perhaps to proc= ess food. Another extremely wides= pread tradition, perhaps occurring in eve= ry tribal society, is ancestor worship.&n= bsp; The ubiquity and apparent antiquity of ancestor worship suggest that= it, too, is an adaptation. By encouraging respect for dead ancestors, ancestor worship encourages the cop= ying of their behavior, which by definition has been successful. (Often, the mere display of tradit= ional behavior is said to please the dead ancestors.) By requiring rituals involving cooperation between co-descendants, the rituals of ancestor worship encoura= ge enduring kinship cooperation. This effect—the encouragement of cooperation between living kin, including= the transmission of traditions from ancestor to descendant—appears to constitute the effect of ancestor worship that has led to its increase thro= ugh the generations, and may have been a critical factor in replacing peoples without ancestor worship. Such cooperation between distant kin and the transmission of complex traditions—including language, religion, political behavior, subordin= ate behavior, art, morality—today constitute the basis of human society everywhere.

&nbs= p; But how can the success of a tradition be measured? The most important fact is that it cannot be measured merely by counting surviving offspring or grandchildren,= for traditions are a K-strategy. = Let me now explain.

&nbs= p; In sociobiology, the measure of a trait’s success is reproductive success. But a selection for a K-strategy is always at the expense of “r,” reproduction. A K-strategy not only involves put= ting more parental resources into fewer offspring (and hence having fewer offspring), but having offspring, a= nd more distant descendants, who also reduce their reproduction. All of them reduce their reproduct= ion to benefit their offspring. To a= rgue that K-strategy reduces the total number of offspring in order to maximize = the number of offspring that survive, ignores the fact that the surviving offsp= ring will reduce their number of offspring, and so on. Thus, a K-trait’s success ca= nnot be measured by counting reproductive output, surviving offspring, or even grandchildren. While an r-str= ategy is always potentially more succ= essful than a K-strategy (for example, a thousand offspring can have a thousand offspring, etc.), when it comes into competition with K-oriented individual= s—those who receive more parental resources—the r-strategists, obviously, can lose.&nb= sp; Indeed, the competitive edge gained by the K-strategist vis-à= -vis the r-strategist may be one of the main benefits of the K-strategy.

&nbs= p; The sociobiological focus on counting offspring or grandchildren will not reveal the ultimate success of a K-strategy. So long as a trait leads to offspring and descendants having slightly more than two offspring on average, it will be successful. Humans, distinguished from all oth= er species by an enormous amount of ancestrally encouraged tradition, exhibit a uniquely extreme K-strategy. = Humans not only reduce their reproduction to teach their offspring traditions, they urge their offspring to do the same and to pass on this behavior to their descendants. The teaching and learning of traditions is at the expense of reproduction.

   &nbs= p;        Let’s not forget that any phenotype is likely to have some effect on one’s descendant-leaving potential. When the phenotype is inheritable, its frequency is subject to its own influence= on leaving descendants. Darwinian natural selection applies to any inheritable phenotype. Because traditions can be inherite= d at one hundred percent (100%) frequency, in contrast to genes—all descendants can inherit a trad= ition. Traditions, therefore, can have a = much more immediate and powerful effect on their subsequent frequency than genes= .

   &nbs= p;        The realization that traditions respond to natural selection allows a new appro= ach to human behavior. For exampl= e, why have certain populations of humans so rapidly come to replace other peoples? The descendants of t= he original Bantu tribe came to replace other native peoples throughout most of sub-Saharan Africa during that last two thousand years. Descendants o= f the “original” Indo-European population have come to replace, over time, the descendants of most peoples living between what is now Bangladesh and Ireland. What accounts for the incredible s= pread of the original Austronesian (formerly Malayo-Polynesian) speaking peoples, originally from Southeast Asia, apparently, but now covering a huge span of= the world, from the island of Madagascar, off Africa, to the Hawaiian Islands, during the last several thousand years?

   &nbs= p;        If we accept that traditions are descendant-leaving strategies subject to natu= ral selection, we can conclude that it is the effect of new, distinctive traditions, and not just technological ones, which has led some individuals= to such great success in leaving descendants at the expense of other peoples without those traditions. Technological innovations, in contrast to social traditions, often depend on considerable occupational specialization, which probably occurs o= nly in large populations of cooperating individuals. Such large populations of cooperat= ing individuals are probably a result of certain new social traditions, new ways of behaving toward one another, including the acceptance of subordination to a hierarchy. Such social traditions are usually created by a religious prophet.

   &nbs= p;        For example, monogamy, or more accurately the prohibition of polygyny, is widespread among those currently speaking an Indo-European language, who now occupies most countries from Europe to t= he Indian subcontinent. This sug= gests that the prohibition of polygyny had become a tradition before the Indo-European speakers began to spread, some six or seven thousand years ago. Thus, there is the possi= bility that this prohibition, which had the effect of reducing competition between males for females, provided conditions that favored male-male cooperation.<= span style=3D'mso-spacerun:yes'> Based on what we now know of the o= rigins of such prohibitions, it was probably pronounced by a religious prophet, who would also have encouraged rituals that had the effect of promoting coopera= tion between those monogamous males. The resulting increase in numbers of social relationships for the average individual would enhance the ability of those individuals to compete with outsiders who would not be supported by such an extensive set of social relationships. Individuals wi= th more social relationships would be more likely to be successful when compet= ing for land, females, anything valuable, against individuals with smaller soci= al networks. Thus, the tradition= of monogamy may have been involved directly in leading to the replacement of t= he peoples who previously occupied the territories now occupied by the descend= ants of ancient Indo-Europeans. Mo= nogamy has other consequences. In co= ntrast to polygynous tribal societies, in monogamous societies it is women, rather than men, who are the one who decorate themselves to compete for (high rank= ing monogamous) mates. A wife of = such a male does not have to share her husband’s resources with co-wives, so= all his resources can be directed toward her offspring. The dowry, as opposed to bride pri= ce, is part of this competitive strategy. Perhaps nowhere is the contrast between monogamy and polygyny in the same society so clearly seen as in India. The Hindu females use the dowry and their gorgeous saris to compete for a high ranking husband, while Muslim females wear attire that obscures all attractive female attributes and they receive a bride price from their polygynously inclined, competitive husband= s.

   &nbs= p;        A focus on descendant-leaving, rather than reproductive-strategies, and on culture, not as a product of a social group but as a descendant-leaving strategy, makes sense of more than widespread and ancient traditions. Recognition that the transmission = of traditions has been powerfully selected for during the last few million yea= rs may best account for a number of physiological features that distinguish hu= mans from other animals, and which have been most intractable to explanation. For example, the rapid selection f= or our huge brains during the last couple of million years, at enormous cost to fe= males and their offspring during labor, including the death of both, cannot be explained by out penchant for hunting or fighting one another, as has been suggested elsewhere. No hunte= rs or fighters in other species have a brain that comes close to the size of ours. Our uniquely large brai= n can be accounted for by an intense selection for the intelligence required for transmission and acquisition of traditions from ancestor to descendant (cf. Humphrey, and Alexander). After all, the first indication of= an increased brain size, occurring in the more than two million year old skull= of Homo Habilis, is accompanied by stone tools. Stone tools imply a tradition. Because stone tool making is trans= mitted from male to male in virtually every known society (Murdock), this first evidence of tool making suggests father to son transmission, and hence marriage.

   &nbs= p;        Other features, physically unique to humans can also be seen as consequences of a selection for the massive transmission of traditions, as we have suggested = elsewhere (Steadman and Palmer).

   &nbs= p;        Menopause can be seen as a result of a selection for children to receive great amount= s of tradition. Human females have= come to live one-third of their life beyond their reproductive age, in order to favor children already born over new offspring unlikely to receive sufficie= nt traditions. Also, every new b= irth of a large headed baby would threaten her and hence the motherly care requi= red for her existing children.

   &nbs= p;        The selection for hidden ovulation also can be explained as a result of the selection for the increasingly intensive transmission of traditions from mo= ther to offspring. Trivers argues = that a person’s choosiness of a mate is based on his/her degree of K-contrib= ution. The uniquely intensive human female investment of traditions in each offspring, should lead to the selection of females to be uniquely choosy of their mate. Hidden ovulation—not adverti= sing when she [a woman] can be impregnated—allows the female to be extreme= ly choosy, even though she will miss many reproductive opportunities. In no other species, apparently, h= as the female’s choosiness been worth such a cost; reproduction has always b= een more important ultimately than the female’s choosiness. Because of hidden ovulation, a female’s chosen mate would need to stay with her for some time to ens= ure her pregnancy. Such long term investment costs for the male should disincline him to leave her in order to find another female who would accept him, and begin the replacement costs anew. This situation could le= ad him eventually to help care for, and transmit traditions himself to, his offspring. This, in turn, cou= ld lead to actual traditions of fatherly behavior and the sexual division of labor, including traditions of males producing tools and hunting.

   &nbs= p;        Human females, in contrast to all other mammals, have permanently enlarged breasts. As we have described elsewhere (Coe and Steadman, 1995), human breasts can best be understood as= a communication that indicates a female’s potential value as a wife: th= e growth of her breasts indicate that she is entering her reproductive years, and th= eir angle or tilt indicate how many reproductive years she has remaining. That is, when a male marries a fem= ale with horizontal breasts he can benefit from her entire reproductive potential. In societies where females do not cover their breasts, breasts do not seem erotic. Only when females come to cover th= eir breasts, in an attempt to hide their reproductive potential, do males become extremely interested in detecting the condition of female breasts. In one New Guinean society in whic= h I spent two and one half (2 ½) years, uncovered breasts are no more er= otic than slender legs or a long nose. Indeed, breasts are called “milks” and are not involved = in sexual foreplay; they are indicators of three stages of life [upright breas= ts =3D ideal reproductive age; angled breasts =3D advanced reproductive age; flacc= id breasts =3D post-reproductive age]. In modern society, brassieres (and now plastic surgery) are used to deceive males into thinking the female is about 19 years old, the age at wh= ich a new wife can begin to maximize a male’s reproduction (cf. Symons, 1979).

   &nbs= p;        Finally, [I’ll discuss] female orgasm. Because a female is more likely to orgasm in an enduring mating relationship (Tarvis and Sadd), and apparently when she does orgasm she is likely to be more faithful (Chesham), female orgasm may be an adaptation. It would have been selected to inc= rease a husband’s confidence in his paternity of his mate’s offspring, which should influence him to be more likely to care for the children. Thus female orgasm, by increasing = the likelihood that a female’s children would be supported by an adult ma= le, would enhance her descendant-leaving potential.

   &nbs= p;        Perhaps none of these hypotheses will stand up to careful scrutiny. The point I’m trying to make= here is that we can attempt to explain the persistence and spread of a particular tradition in the same way as any stable, inheritable phenotype; that is, by= its contribution to an individual’s success in leaving descendants. To measure such success we cannot = simply count offspring or grandchildren, for traditions are K-strategies, which are always at the expense of reproduction.&nbs= p; Culture is a descendant-leaving strategy, not a reproductive strateg= y. So long as a tradition leads to so= mewhat more than two offspring, who in turn have somewhat more than two offspring,= on average, such a tradition can continue to increase in frequency along with = the ancestor’s descendants, at the expense of more reproductively oriented phenotypes. But the success o= f a tradition, like any phenotype, is always influenced by its environment, including the presence of alternative traditions.

   &nbs= p;        In sum, I argue that culture has been selected for as traditions, which consti= tute an intensive K-strategy. Beca= use such a strategy is always at the expense of reproduction, its success canno= t be measured by counting children or grandchildren, but only more distant descendants. Traditions are n= ot “r,” but are descendant-leaving strategies.

[Addendum]

(Somewhere use the following)

???????

   &nbs= p;        A selection for culture is in fact a selection for the transmission of tradit= ions from ancestor to descendant.

???? Chi= mpanzee mothers have been identified transmitting learned “anting” and “termiting” techniques to their offspring, and macaques have be= en observed transmitting food washing methods to their offspring.

(???? If= we can generalize Harlow’s findings on the rhesus monkey to all mammals, motherly behavior seems to depend on being mo= thered, and hence, to some extent is itself traditiondal. Include????)