The Advent of Sociobiology Sheds New Light on Animal Societies

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The Advent of Sociobiology Sheds New Light on Animal Societies

Overview

Sociobiology is the attempt to understand the biological origins and development of animal societies—including human society—using the Darwinian theory of natural selection. It is based in part on the observation that certain behaviors in animal societies are universal, meaning they must be based on hereditary instincts. This includes behaviors that make social life possible, such as cooperation, division of labor, social hierarchy, etc. Sociobiology explains the origins of these social instincts as the product of natural selection and explains hereditary behaviors as traits that help animals survive and reproduce.

Background

Charles Darwin (1809-1882) himself had grappled with the problem of social behavior and ethics in human society. In The Descent of Man (1871) he expressed the view that human ethics was similar to the social instincts of other animals, such as wolves or apes, but more highly developed because of the human capacity to reason. He believed that the social instincts were hereditary in humans, just as they are in other animals.

A difficulty Darwin faced was how to explain the origin of ethical behavior in naturalistic terms. After all, his theory of natural selection through the struggle for existence implied that all organisms were competing for scarce resources. How could social instincts or ethical behavior develop if the individual practicing selfless behavior would perish at a greater rate than more selfish individuals? Wouldn't the more ruthless individuals in any species triumph over the more meek, humble, or loving individuals in the struggle for existence? The explanation Darwin provided to explain this puzzling situation is often called group selection, though Darwin never used that term. Group selection means that even though selfless behavior (altruism), such as sacrificing one's life for the sake of another, does not benefit the individual in the struggle for existence, it benefits the individual's group (family, tribe, or nation). The group that has the greatest amount of altruism or self-sacrifice would thus supplant groups that cooperate less. Thus the groups with greater social instincts would pass on their traits to the next generation.

By the mid-twentieth century most biologists rejected the idea of group selection, insisting that selection operated only on individuals. Most scholars in the humanities and social sciences considered human ethics environmentally rather than genetically determined, placing human ethics beyond biological explanation. These factors militated against Darwinian explanations of social behavior, especially in human society.

Nevertheless, sociobiology exploded on the scene as a new scientific research field in the 1960s and 1970s. Konrad Lorenz (1903-1989) and Nikolaus Tinbergen (1907-1988) laid the groundwork by arousing interest in the biological roots of animal behavior. They founded a new branch of biology—ethology—to rigorously analyze and explain animal behaviors and the hereditary instincts on which behavior is based. Lorenz and Tinbergen shared the 1973 Nobel Prize in medicine for their work in ethology.

However, it was W. D. Hamilton's seminal paper on kin selection in 1964 that made sociobiology plausible and won over its strongest advocate, the Harvard biologist Edward O. Wilson (1929- ). Hamilton grappled with the same issue as Darwin—the origin of altruistic behavior in social animals. He argued that natural selection can indeed account for the origin of hereditary altruistic behaviors in social animals. He believed that by furthering the interests of close kin, who share many of the same genes, a self-sacrificing individual is actually helping promote the reproduction of his or her own genes, even if the individual does not leave any direct offspring. For example, among social insects there are often neuter castes of workers or soldiers, who cannot reproduce, but who work to support the queen; only the queen can reproduce. If natural selection operates only at the individual level, it is hard to explain the origin of these neuter castes. However, Hamilton pointed out that because all individuals in the colony are descended from the queen, they all share genes with the queen. Thus helping the queen survive and reproduce means they can pass on their own genes (including the biological social instincts) to the next generation.

Impact

Other works in the 1960s promoted the idea that animal behaviors, including human ethical behavior, can be understood as instincts produced through Darwinian evolution. In the mid-1960s Lorenz, Desmond Morris, and Robert Ardrey wrote popular works arguing that human aggression and territoriality are hereditary instincts based on evolutionary competition. The idea that human behavior is conditioned by hereditary instincts began to gain some currency in psychology and the social sciences as well.

Wilson, building on Lorenz and Hamilton's ideas, became the most prominent proponent of sociobiology and brought it to the attention of the wider public. His own specialization was ant biology, and in 1971 he published The Insect Societies, applying sociobiology to his field of expertise. Then in 1975 he expanded his treatment of sociobiology to include all social animals, including humans, in Sociobiology: The New Synthesis. In this work he argued that instincts producing social behavior are genetically determined and are produced through natural selection. He identified various behavioral traits that are universal within social animal species and showed the survival and reproductive advantage such traits endow on their possessors.

Wilson's Sociobiology spawned a public debate, as some scientists and many social scientists vigorously rejected his genetic determinism, especially as applied to human society. In response to the harsh criticism he received, Wilson expanded his treatment of human sociobiology in On Human Nature (1978), which won him a Pulitzer Prize. In this work he analyzed behaviors and ethical standards that are universal or almost universal in human societies. He examined human tendencies toward division of labor between the sexes, altruism toward kin, territorial aggression, incest avoidance, tribalism, male dominance, etc. He claimed humans had genetic predispositions for these behaviors.

Two of his colleagues at Harvard, the geneticist Richard Lewontin and the paleontologist Stephen Jay Gould (1941- ), both staunch Darwinists, led the opposition against sociobiology, and they are still Wilson's strongest critics. They argued that human social and ethical behavior is not biologically determined. They considered Wilson's views politically dangerous, since it seems to suggest that hierarchy, male dominance, and tribalism are natural and unavoidable in human society. Wilson was accused of racism, sexism, and justifying the oppressive status quo, charges which spawned public protests against Wilson. At the American Association for the Advancement of Science meeting in Washington in February 1978, Wilson was doused with ice water during his presentation by antiracist demonstrators.

Wilson responded to his critics, who, he claimed, misunderstood his position. He asserted that he was not strictly a genetic determinist, because in his view genes do not compel specific behaviors, but only make humans predisposed toward certain behaviors. He also acknowledged that culture, even though linked to genetic tendencies, plays a significant role in the development of specific behaviors and moral codes. Even cultural traits, in his view, evolve through natural selection in a process he termed "gene-culture coevolution," since cultural traits that promote survival and reproduction will be selected, just as biological traits are.

Despite widespread criticism, Wilson also gained important allies and wielded considerable influence, especially among biologists. Richard Dawkins in his famous book, The Selfish Gene (1976), helped promote sociobiology, as have many of his students and followers, such as Helena Cronin. In the 1980s and 1990s there was a huge outpouring of works by biologists, anthropologists, psychologists, and other scholars promoting sociobiology and evolutionary ethics. Scientists are studying and explaining ever more animal and human behaviors within the perspective of sociobiology. Some prefer to call this new field evolutionary psychology, especially when dealing with human behavior.

Sociobiology has become a hot topic in the popular media. In 1977 Time magazine carried a cover story on sociobiology. In 1995 Robert Wright, a popularizer of evolutionary psychology in his The Moral Animal: Evolutionary Psychology and Everyday Life, wrote a cover story for Time magazine, in which he explained the human male's alleged proclivity for adultery as a genetic predisposition explicable through Darwinian theory. Sociobiologists and evolutionary psychologists have tried to explain everything from infanticide to homosexuality to President Clinton's sexual escapades as genetic tendencies produced through Darwinian evolution. One of the most prominent recent advocates of evolutionary psychology is MIT psychology professor Steven Pinker, whose book, How the Mind Works (1998), reached a popular audience.

Sociobiology and evolutionary psychology, especially as applied to humans, remain highly contested topics today. They have many supporters, but also many detractors. Adherents consider sociobiology the key to understanding who we are as humans, the solution to the riddle of human nature. However, many still object to the genetic determinism and the just-so stories that are so often used to support human sociobiology. One prominent biologist, Steve Jones, has asserted that "the attempt to explain the modern world in terms of the sex life of the Stone Age is the biggest load of hogwash ever foisted on to an unsuspecting public."

RICHARD WEIKART