Sociobiology

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SOCIOBIOLOGY

Sociobiology denotes the attempt to provide a biological explanation for the social behavior of animals, including humans, although the focus is more often on social insects such as ants and honey bees. Because ethics is also concerned with social behavior among human beings, achievements in sociobiology may also have implications for a possible science of ethics.

The Darwinian Background

As a term the word sociobiology first appears in Principles of Animal Ecology (1949) by Warder C. Allee, Alfred E. Emerson, et al., but the subject matter is much older. In On the Origin of Species (1859), Charles Darwin argued that there is constant population pressure brought on by the fact that numbers of organisms always outstrip food and other resources. There is therefore a constant struggle for existence. Some organisms have features enabling them to better succeed in the struggle, and thus there is a natural selection of the winners over the losers. This leads to evolution, but evolution of a special kind. Selection produces and perfects features useful in the struggle—organisms have adaptations such as the hand and the eye that aid them in survival (and, even more importantly, to reproduce).

Darwin realized that behavior is as much part of an animal's repertoire in the struggle for existence as are any physical adaptations. He was particularly interested in social behavior such as that of the hymenoptera (the ants, bees, and wasps). His interest was spurred not only by the phenomenon itself but because (in Darwin's opinion) such behavior seems to go against the workings of selection. Darwin believed that the struggle for existence pits every organism against every other organism, and hence selection can only promote adaptations that are valuable to the individual. (In contemporary language, Darwin was an individual selectionist rather than a group selectionist.) How then do organisms develop social features that seem to help the nest, perhaps even at the cost of total sacrifice of the interests of the individual? Sterile workers apparently spend their whole lives looking to the needs of their mothers and siblings. Eventually Darwin came to believe that the nests of social insects should be regarded as one large superorganism, rather than a group of individuals working together. In that way, the individuals in a nest are more parts of the whole (like the heart and liver are parts of the human body) rather than organisms existing in their own right with their own interests.

For a number of reasons, in the century after On the Origin of Species was published, the study of behavior by biologists lagged behind other areas of evolution. First behavior is much more difficult to record and measure than are physical characteristics. Experimentation is particularly difficult, for it is notoriously true that animals change their behaviors in artificial conditions. Secondly practitioners of the new social sciences thought that they exclusively should examine behavior, and that biology had no place in their endeavors. Unfortunately there existed a strong ideology that experience and training are the cause of most, if not all, behavior, and hence evolutionary factors tended to be discounted before any research was done. Continental students of behavior known as ethologists were a notable exception to this indifference to evolutionary theory, although their work was (as judged by twenty-first century standards) hampered by unjustified assumptions about the significance of group selection.

Breakthroughs in the 1960s

Major breakthroughs occurred in the 1960s, due, in large part, to the work of William Hamilton (1936–2000) in England. Promoting the theory now known as kin selection, Hamilton, then a graduate student, pointed out that in modern terms, selection is equivalent to passing on a particular individual's genes (or rather copies of those genes) more effectively than competitors. However when a person's close relatives reproduce, because they share copies of that person's genes, they also pass on those same copies: reproduction by proxy as it were. Normally it is biologically most efficient to reproduce oneself because (except for identical twins) an individual cannot be genetically more closely related to any other being. Hamilton argued there are some exceptions to this general rule. The hymenoptera particularly have an unusual reproductive system, with females having both mothers and fathers and males having only mothers. Queens get all the sperm they will ever use on the nuptial flight. To produce a female, the queen releases a sperm; in contrast, in producing male offspring, no sperm is released. Thus sisters (50% ? + 50% ? x ½ = 75%) are more closely related than mothers and daughters (50% ? x ½ + 50% ? x ½ = 50%), and so, from an evolutionary perspective, a nest member is better off raising fertile sisters than fertile daughters. From an individual selection perspective, sociality is advantageous.

After Hamilton others proposed theories using an individualistic perspective. One important contribution was Robert Trivers's notion of reciprocal altruism, based on the you scratch my back and I'll scratch yours principle, which holds that some forms of sociality succeed because organisms gain more through cooperation than through conflict. Also significant were insights based on the use of game theory, particularly the idea of an Evolutionarily Stable Strategy (ESS). A whole group is sometimes less well adapted than it could be because self-interest is paramount. Sex ratios are a case in point. Females do not need a large number of males for fertilization. But because 50:50 seems to be a more stable balance in the population, the group maintains a surplus of males, instead of a more efficient 10:90 male to female ratio. Building on ideas like this, the study of evolution started to change dramatically, and by the 1970s the study of social behavior, in theory and in practice, became one of the most advanced and exciting areas of evolutionary inquiry. The ideas were presented in popular form by British biologist Richard Dawkins in his The Selfish Gene (1976), and in what became the bible of the movement and gave the field its name, Sociobiology: The New Synthesis (1975), by the American scholar of the study of social insects, Edward O Wilson.

Controversies

These works, Wilson's in particular, were highly controversial, mainly (although not exclusively) because they extended to humans. Much like Darwin himself, having surveyed social behavior in the animal world from the most primitive forms to the primates, Wilson argued that Homo Sapiens is part of the evolutionary world in its behavior and culture. Although he did allow that experience and training can have some effects, Wilson believed that genes are the real key to understanding human thought and behavior. In male-female relationships, in parent-child interactions, in morality, in religious yearnings (a very important phenomenon for Wilson, a Southerner), in warfare, in language, and in much else, biology matters crucially.

Social scientists and left-leaning biologists (especially Richard Lewontin and Stephen Jay Gould), and philosophers (especially Philip Kitcher in a witty attack, Vaulting Ambition), accused sociobiologists—particularly human sociobiologists—of a multitude of sins. Epistemologically these detractors judged the work of sociobiologists to be false, and then (not entirely consistently) charged them with producing ideas and theories that are not falsifiable. One particularly effective rhetorical charge was that sociobiologists's claims are akin to the Just So stories by Rudyard Kipling, in which a fantastical tale is created (i.e., that of how the elephant's nose is long because it was pulled by a crocodile) and then is alleged to be fact. Sociobiologists were also found to be wanting ethically. Their work was attacked as sexist, racist, homophobic, capitalist, and in short, guilty of every possible transgression that exists in a patriarchal, unjust society. They were accused of supporting the status quo in Western societies, and of pretending to give genuine scientific answers to bolster what were really ideological convictions.

There was undoubtedly some truth to all of these claims. Yet some change can be progress, and there is little doubt—at the animal level particularly—that evolutionists have taken full note of critics' complaints and worked hard to address them. Modern techniques, particularly those that employ the insights of molecular biology, have been of great help here. For instance many sociobiological claims concern parenthood. If males are competing for females, for instance, and (as in birds) males are also contributing to childcare, one expects efforts to be tied to reproductive access and success. But while it is difficult if not impossible to determine paternity with traditional methods, that Gordian Knot is cut as soon as one starts using genetic fingerprints. Not only are the scientific claims testable but in many cases they have been found to be correct. Animal sociobiology is no more tentative than other scientific fields. It can be persuasively argued that in science bold conjectures are needed in abundance. However when those conjectures are accepted as fact without being tested, there is a problem. Science requires continual, rigorous challenge.

Human sociobiologists argue that they too have theories that can be, and are, put to the test, such as theories about infanticide, showing that this occurs when and generally only when it is in the biological interests of parents not to have all of the children to which they (or sometimes, rivals) have produced. One well-known theorem (with much support in the animal realm) asserts that females who are more fit will tend to skew birth rates toward males, and less fit females toward females. The reason for this is that even unfit females generally get impregnated, whereas if there is competition among males—and there usually is—the fitter male tends to get the prize. Hence because fit mothers are more likely than unfit mothers to have fit offspring, for fit mothers having males is a good strategy, whereas for unfit mothers having females is a good strategy. There is incidentally no necessary presumption that this always requires conscious intention—fluctuating hormones, for instance, might be the proximate causes. Human sociobiologists argue that this also occurs in human societies, with the members of upper classes tending to dispose of daughters, either physically by allowing them to die or giving them away shortly after birth, or through other methods that effectively prevent reproduction even without killing (for instance, by forcing daughters into religious orders that require celibacy thereby effectively preventing them from reproducing). In recent years, human sociobiology has changed into what is now called evolutionary psychology. The emphasis is less on behavior and more on the mental traits that lead to behavior. This view is still philosophically controversial, with much debate about how and whether one can talk of psychological characteristics as being innate (and how one would test the theory).

Sociobiologists have countered vigorously against the social and ethical charges levied against them. Almost without exception, human sociobiologists have not had significant social agendas and are greatly concerned by the misuse that can (and sometimes is) made of their work. They repudiate strongly the charge that they are crypto-nazis or subscribers to other vile doctrines, and deplore the fact that sometimes people favorable to these ideas invoke the authority of sociobiology in support. They stress that differences between races, for instance, are far less than similarities, and in any case differences in themselves do not necessarily spell superiority or inferiority. Although their work has been much criticized by feminists, human sociobiologists respond that pointing out differences between males and females is not in itself sexist. Indeed one might argue that not to recognize differences can be morally wrong. If boys and girls mature at different rates, insisting that they all be taught in the same ways could be detrimental to both sexes. In more specific issues also sociobiology is not necessarily erroneous or promoting an immoral agenda. To hypothesize that something such as sexual orientation is dictated by an individual's genes (and that there is a pertinent underlying evolutionary history to explain it) could be a move toward recognizing that all people are equally worthy of moral tolerance and respect.

There is ongoing philosophical debate over all of these issues. In the early twenty-first century there is renewed interest in the possible evolutionary underpinnings of religion. It is clear that sociobiology—animal and human, and by whatever name the field is known—is not about to disappear, and is in fact a thriving area of inquiry.

MICHAEL RUSE