Sociological Theory

What is Sociobiology?

Sociology 2111

Department of Sociology and Anthropology

From Edward O. Wilson, "Introduction: What is Sociobiology?" In Michael S. Gregory, Anita Silvers, and Diane Sutch (Eds.). 1978. Sociobiology and Human Nature: An Interdisciplinary Critique and Defense. San Francisco, CA: Jossey-Bass, pp. 1 - 12.

Introduction: What Is Sociobiology?

I was surprised--even astonished--by the initial reaction to Sociobiology: The New Synthesis (1975a). When the book was published in 1975, I expected a favorable reaction from other biologists. After all, my colleagues and I had merely been extending neo-Darwinism into the study of social behavior and animal societies, and the underlying biological principles we employed were largely conventional. The response was in fact overwhelmingly favorable. From the social scientists, I expected not much reaction. I took it for granted that the human species is subject to sociobiological analysis no less than to genetic or endocrinological analysis; the final chapter of my book simply completed the catalogue of social species by adding Homo sapiens. I hoped to make a contribution to the social sciences and humanities by laying out, in immediately accessible form, the most relevant methods and principles of population biology, evolutionary theory, and sociobiology. I expected that many social scientists, already convinced of the necessity of a biological foundation for their subject, would be tempted to pick up the tools and try them out. This has occurred to a limited extent, but there has also been stiff resistance. I now understand that I entirely underestimated the Durkheim-Boas tradition of autonomy of the social sciences, as well as the strength and power of the antigenetic bias that has prevailed as virtual dogma since the fall of Social Darwinism.

I did not even think about the Marxists. When the attacks on sociobiology came from Science for the People, the leading radical left group within American science, I was unprepared for a largely ideological argument. It is now clear to me that I was tampering with something fundamental: mythology. Evolutionary theory applied to social systems is an extension of the great Western traditions of scientific materialism. As such, it threatens to transform into testable hypotheses the assumptions about human nature made by some Marxist philosophers. Its first line of evidence is not favorable to those assumptions, insofar as most traditional Marxists cling to a vision of human nature as a relatively unstructured phenomenon swept along by economic forces extraneous to human biology. Marxism and other secular ideologies previously rested secure as unchallenged satrapies of scientific materialism; now they were in danger of being displaced by other, less manageable biological explanations. The remarkably harsh response of Science for the People is an example of what Hans Kung (1976) has called the fully of the theologians.

But much of the confusion has come from a simple misunderstanding of the content of sociobiology. Sociobiology is defined as the systematic study of the biological basis of all forms of social behavior, including sexual and parental behavior, in all kinds of organisms including humans. As such, it is a discipline--an inevitable discipline, since there must be a systematic study of social behavior. Sociobiology consists mostly of zoology. About 90 percent of its current material concerns animals, even though over 90 percent of the attention given to sociobiology by nonscientists, and especially journalists, is due to its possible applications to the study of human social behavior. There is nothing unusual about deriving principles and methods, and even terminology, from intensive examinations of lower organisms and applying them to the study of human beings. Most of the fundamental principles of genetics and biochemistry applied to human biology are based on colon bacteria, fruit flies, and white rats. To say that the same science can be applied to human beings is not to reduce humanity to the status of these simpler creatures.

Nor is there anything new or surprising about having such a discipline within the family of the biological sciences. The term sociobiology was used independently by John P. Scott in 1946 and by Charles F. Hockett in 1948, but the word was not picked up immediately by others. In 1950, Scott, who had been serving as secretary of the small but influential Committee for the Study of Animal Behavior, suggested sociobiology more formally as a term for the "interdisciplinary science which lies between the fields of biology (particularly ecology and physiology) and psychology and sociology" (p. 1004). From 1956 to 1964, Scott and others constituted the Section on Animal Behavior and Sociobiology of the Ecological Society of America. This Section became the present Animal Behavior Society. During 1950-1970, sociobiology was employed intermittently in technical articles, a usage evidently inspired by its already quasi-official status. But other expressions, such as biosociology and animal sociology, were also employed. When I wrote the final chapter of The Insect Societies (1971), which was entitled "The Prospect for a Unified Sociobiology" and when I wrote Sociobiology: The New Synthesis (1975a), where I suggested that a discrete discipline should now be built on a foundation of genetics and population biology, I selected the term sociobiology rather than some other, novel expression because I believed it would already be familiar to most students of animal behavior and hence more likely to be accepted.

Pure sociobiological theory, being independent of human biology, does not imply by itself that human social behavior is determined by genes. It allows for any one of three possibilities. One is that the human brain has evolved to the point that it has become an equipotential learning machine entirely determined by culture. The mind, in other words, has been freed from the genes. A second possibility is that human social behavior is under genetic constraint but that all of the genetic variability within the human species has been exhausted. Hence our behavior is to some extent influenced by genes, but we all have exactly the same potential. A third possibility, close to the second, is that the human species is prescribed to some extent but also displays some genetic differences among individuals. As a consequence, human populations retain the capacity to evolve still further in their biological capacity for social behavior.

I consider it virtually certain that the third alternative is the correct one. Because the evidence has been well reviewed in other recent works, most notably Chagnon and Irons (Eds., in press), De Vore (in press), and Freedman (in press), I will not undertake to exemplify it or review it in detail. Instead, let me outline its content.

1. Specificity of human social behavior. Although the variation of cultures appears enormous to the anthropocentric observer, all human behavior together comprises only a tiny subset of the realized social systems of the thousands of social species on earth. Corals and other colonial invertebrates, the social insects, fish, birds, and nonhuman mammals display among themselves an array of' arrangements that it is difficult for human beings even to understand, much less imitate. Even if we were to attempt to duplicate some of these social behaviors by conscious design, it would be a charade likely to create emotional breakdown and a rapid reversal of the effort.

2. Phylogenetic relationships. Our social arrangements most closely resemble those of the Old World monkeys and apes, which on anatomical and biochemical grounds are our closest living relatives. This is the result expected if we share a common ancestry with these primates, which appears to be an established fact, and if human social behavior is still constrained to some extent by genetic predispositions in behavioral development.

3. Conformity to sociobiological theory. In the case of the hypothesis of genetic constraints on human social behavior, it should be possible to select some of the best principles of population genetics and ecology, which form the foundations of sociobiology, and to apply them in detail to the explanations of human social organization. The hypothesis should then not only account for many of the known facts in a more convincing manner than do previous attempts but should also identify the need for new kinds of' information not conceptualized by the unaided social sciences. The behavior thus explained should be the most general and least rational of the human repertory, the furthest removed from the influence of year-by-year shifts in fashion and convention. There are in fact a substantial number of anthropological studies completed or underway that meet these exacting criteria of postulational-deductive science. Among them can be cited the work of Joseph Shepher (1971) on the incest taboo and sexual roles, Mildred Dickeman (in press) on hypergamy and sex-biased infanticide, William Irons (in press) on the relation between inclusive genetic fitness and the local set of evaluational criteria of social success in a herding society, Napoleon Chagnon (1976) on aggression and reproductive competition in the Yanomamo, William Durham (1976) on the relation between inclusive fitness and warfare in the Mundurucu and other primitive societies, Robin Fox (personal communication) on the relation of fitness to kinship rules, Melvin Konner (1972) and Daniel G. Freedman (1974, in press) on the adaptive significance of infant development, and James Weinrich (1977) on the relationship of genetic fitness and the details of sexual practice, including homosexuality.

4. Genetic variation within the species. By 1977, more than 1,200 loci had been located on human chromosomes through the fine analysis of biochemical and other mutations (McKusick and Ruddle, 1977). Many of these point mutations, as well as a growing list of chromosomal aberrations, affect behavior. Most simply diminish mental capacity and motor ability, but at least two, the Lesch-Nyhan syndrome, based on a single gene, and Turner's syndrome, caused by the deletion of a sex chromosome, alter behavior in narrow ways that can be related to specific neuromuscular mechanisms. The adrenogenital syndrome, which is induced by a single recessive gene, appears to masculinize girls through an early induction of adrenocortical substances that mimic the male hormone.

More complex forms of human behavior are almost certainly under the control of polygenes (genes scattered on many chromosome loci), which in turn create their effects through alternating a wide array of mediating devices, from elementary neuronal wiring to muscular coordination and "mental set" induced by hormone levels. In most instances, the role of behavioral polygenes can be evaluated--but only qualitatively--by the careful application of twin and adoption studies. The most frequently used method is to compare the similarity between identical twins, who are known to be genetically identical, with the similarity between fraternal twins, who are no closer genetically than ordinary siblings. When the similarity between identical twins proves greater, this distinction between the two kinds of twins is ascribed to heredity. Using this and related techniques, geneticists have found evidence of a substantial amount of hereditary influence on the development of a variety of traits that affect social behavior, including number ability, word fluency, memory, the timing of language acquisition, sentence construction, perceptual skill, psychomotor skill, extroversion and introversion, homosexuality, the timing of first heterosexual activity, and certain forms of neurosis and psychosis, including the manic-depressive syndrome and schizophrenia.

In most instances, there is a flaw in the results that renders most of them less than definitive: Identical twins are commonly treated more alike by their parents than are fraternal twins. They are instructed in a more nearly parallel manner, dressed more alike, and so forth. In the absence of better controls, it is possible that the greater similarity of identical twins could, after all, be due to environmental influences and not their genetic identity. However, new and more sophisticated studies have begun to take account of this additional factor. Loehlin and Nichols (1976), for example, analyzed many aspects of the environments and performances of 850 sets of twins who took the National Merit Scholarship test in 1962. The early histories of the subjects, as well as the attitudes and rearing practices of the parents, were taken into account. The results showed that the generally more similar treatment of the identical twins cannot account for their greater similarity in general abilities and personality traits or even in ideals; goals, and vocational interests. It is evident that either the similarities are based in substantial part on genetic identity or else environmental agents were at work that remained hidden to Loehlin and Nichols.

My overall conclusion from the existing information is that Homo sapiens is a typical animal species with reference to the quality and magnitude of the genetic diversity affecting its behavior. I also believe that it will soon be within our ability to locate and characterize specific genes that alter the more complex forms of social behavior. Obviously, the alleles discovered will not prescribe different dialects or modes of dress. They are more likely to work measurable changes through their effects on learning modes and timing, cognitive and neuromuscular ability, and the personality traits most sensitive to hormonal mediation. If social scientists and sociobiologists somehow choose to ignore this line of investigation, they will soon find human geneticists coming up on their blind side. The intense interest in medical genetics, fueled now by new methods such as the electrophoretic separation of proteins and rapid sequencing of amino acids, has resulted in an acceleration of discoveries in human heredity that is certain to have profound consequences for the study of genetics of social behavior.

I wish now to take up the concerns expressed about human sociobiology in the chapters to follow in Sociobiology and Human Nature. Most have been expressed by other authors in one form or another before the NEXA conference. I have no desire to rebut specific points raised by individual authors. This would in any case be unfair by the ordinary canons of debate, and Sociobiology and Human Nature surely is a debate. Rather, I want to discuss in broader terms the ways in which the several intellectual traditions represented so well by the other contributors might be reconciled with the relatively uncompromising biological approach I have taken up to the present time.

The first area of conflict that can be resolved is the relation of genes to culture. Many social scientists see no value in sociobiology because they are persuaded that variation among cultures has no genetic basis. Their premise is right, their conclusion wrong. We can do well to remember Rousseau's dictum that those who wish to study humans should stand close, while those who wish to study humanity should look from afar. The social scientist is interested in the often microscopic, but important, variations in behavior that almost everyone agrees are due to culture and the environment. The sociobiologist is interested in the more general features of human nature and the limitations that exist in the environmentally induced variation. He or she is especially interested in the fact that, although all cultures taken together constitute a very great amount of variation, their total content is far less than that displayed by the remaining species of social animals. By comparing the diagnostic features of human organization with those of other primate species, the sociobiologist aims to reconstruct the earliest evolutionary history of social organization and to discern its genetic residues in contemporary societies. The approach is entirely complementary to that of the social sciences and in no way diminishes their importance--quite the contrary.

Those immersed in the rich lore of the social sciences sometimes reject human sociobiology because it is reductionistic. But almost all of the great advances of science have been made by reduction, in the form of conjectures that are often bold and momentarily premature. Theoretical physics transformed chemistry, chemistry transformed cell biology and genetics, natural selection theory transformed ecology--all by stark reduction, which at first seemed inadequate to the task. Reduction is a method by which new mechanisms and relational processes are discovered. In the most successful case histories of postulational-deductive science, propositions are expressed in forms that can be elaborated into precise, testable models. The other side of reduction, the antithesis of the thesis, is synthesis. As the new principles and equations are validated by repeated testing, they are used in an attempt to reconstitute the full array of the subject's phenomena. Karl Popper (1974) has correctly suggested that philosophical reductionism is wrong but that methodological reductionism is necessary for the advancement of science. Here is how I tried to summarize the role of sociobiological reduction in an earlier review (Wilson, 1977, p. 138):

The urge to be reductionistic is an understandable human trait. Ernst Mach [1974] captured it in the following definition: "Science may be regarded as a minimal problem consisting of the completest presentment of facts with the least possible expenditure of thought." This is a sentiment of a member of the antidiscipline, impatient to set aside complexity and get on with the search for more fundamental ideas. The laws of his subject are necessary to the discipline above, they challenge and force a mentally more efficient restructuring, but they are not sufficient for its purposes. Biology is the key to human nature, and social scientists cannot afford to ignore its emerging principles. But the social sciences are potentially far richer in content. Eventually they will absorb the relevant ideas of biology and go on to beggar them by comparison.

The strongest redoubt of counterbiology appears to be mentalism. It is difficult--for some it is impossible--to envision the existence of the mind and the creation of symbolic thought by biological processes. "The human mind,'' this argument often goes, "is an emergent property of the brain that is no longer tied to genetic controls. All that the genes can prescribe is the construction of the liberated brain." But the relation between genes, the brain, and the mind is only a practical difficulty, not a theoretical one. Models have already been produced in neurobiology and cognitive psychology that allow at least the possibility of mind as an epiphenomenon of complex but essentially conventional neuronal circuitry. Consciousness might well consist of large numbers of coded abstractions, some fed stepwise through a hierarchy of integrating centers whose lowest array consists of the primary sense cells, others originating internally to simulate these hierarchies. The brain--in Charles Sherrington's (1940) metaphor, the "enchanted loom where millions of flashing shuttles weave a dissolving pattern"--not only experiences scenarios fed to it by the sensory channels but also creates them by recall and fantasy. In sustaining this activity, the brain depends substantially on the triggering effect of verbal symbols. There is also a reliance on what have been called plans or schemata-- configurations within the brain, either innate or experiential in origin, against which the input of the nerve cells is compared. The matching of the real or expected patterns can have one or more of several effects. It can contribute to mental "set," the favoring of certain kinds of sensory information over others. It can generate the remarkable phenomena of gestalt perception, in which the mind supplies missing details from the actual sensory information in order to complete a pattern and make a classification. And it can serve as the physical basis of will: The mind can be guided in its actions by feedback loops that lead from the sense organs to the brain schemata to the neuromuscular machinery and sense organs and back again until the schemata "satisfy" themselves that the correct action has been taken. The mind could be a republic of alternative schemata, programmed to compete for control of the decision centers, individually waxing and waning in power according to the relative urgency of the needs of the body being signaled through other nervous pathways passing upward through the lower brain centers. The mind might or might not work approximately in such a manner. My point is that it is entirely possible for all known components of the mind, including will, to have a neurophysiological basis subject to genetic evolution by natural selection. There is no a priori reason why any portion of the foundation of human social behavior must be excluded from the domain of sociobiological analysis.

Some critics have objected to the drawing of analogies between animal and human behavior, especially as it entails the same terminology to describe phenomena across species. This reservation has always struck me as insubstantial. The definitions and limitations of the concepts of analogy and homology have been well worked out by evolutionary biologists, and it is difficult to imagine why the same reasoning cannot be extended with proper care to the human species. We already speak of the octopus eye and the human eye, insect copulation and human copulation, and earthworm learning and human learning, even though in each of these cases the two species are in different superphyla, and the traits listed were independently evolved. The questions of interest are in fact the degrees of convergence and the processes of natural selection that made the convergence so close. When biologists compare altruism in the honeybee worker with human altruism, no one seriously believes that they are based on homologous genes or that they are identical in detail. Slavery practiced by Polyergus and Strongylognathus ants resembles human slavery in some broad features and differs from it in others, as well as in most details of its execution. By using the same term for such comparisons, the biologist calls attention to the fact that some degree of convergence has occurred and invites an analysis of all the causes of similarity and difference. There is a Greek-derived term for insect slavery--dulosis--but its usage outside entomology would not only complicate language but would also slow the very comparative analysis that is of greatest interest.

I am most puzzled by the occasional demurral that sociobiology distracts our attention from the real needs of the world. The questions are raised, "How can we worry about the origins of human nature when the nuclear sword hangs over us? When people are starving in the Sahel and in Bangladesh and political prisoners are rotting in Argentinian jails?" In response, one can answer, "Do we want to know, in depth and with any degree of confidence, why we care? And, after these problems have been solved, what then?" The highest goals professed by governments everywhere are human fulfillment above the animal level and the realization of individual potential. But what is fulfillment, and to what ends can potential be expanded? I suggest that only a deeper understanding of human nature, which must be developed from neurobiological investigations of the brain and the phylogenetic reconstruction of the species-specific properties of human behavior, can provide humanity with the perspective it requires to formulate its highest social goals.

The excitement of sociobiology comes from the promise of the role it will play in this new humanistic investigation. Its potential importance beyond zoology lies in its logical position as the bridging discipline between the natural sciences on the one side and social sciences and humanities on the other. For years, the chief spokespersons of the natural sciences to Western high culture have been physicists, astronomers, geneticists, and molecular biologists--articulate and persuasive scholars whose understanding of the evolution of the brain and of social behavior was unfortunately minimal. Their perception of values and the human condition was almost entirely intuitive and hence scarcely better than that of other intelligent laypersons. Biology has been employed as a science that accounts for the human body; it concerns itself with technological manifestations such as the conquest of disease, the green revolution, energy flow in ecosystems and the cost-benefit analysis of gene splicing. Natural scientists have by and large conceded social behavior to be biologically unstructured and hence the undisputed domain of the social sciences. For their part, most social scientists have granted that human nature has a biological foundation, but they have regarded it as of marginal interest to the resplendent variations in culture that hold their professional attention.

In order for the fabled gap between the two cultures to be truly bridged, social theory must incorporate the natural sciences into its foundations, and for that to occur biology must deal systematically with social behavior. This competence is now being approached through the two-pronged advance of neurobiology which boldly hopes to explain the physical basis of mind, and sociobiology, which aims to reconstruct the evolutionary history of human nature. Sociobiology in particular is still a rudimentary science. Its relevance to human social systems is still largely unexplored. But in the gathering assembly of disciplines it holds the greatest promise of speaking the common language.


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