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Sociobiology
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Sociobiology is a neo-Darwinian synthesis of scientific disciplines that attempts to explain social behavior in all species by considering the evolutionary advantages the behaviors may have. It is often considered a branch of biology and sociology, but also draws from ethology, anthropology, evolution, zoology, archaeology, population genetics and other disciplines. Within the study of human societies, sociobiology is closely related to the fields of human behavioral ecology and evolutionary psychology.
Sociobiology investigates social behaviors, such as mating patterns, territorial fights, pack hunting, and the hive society of social insects. Just as selection pressure led to animals evolving useful ways of interacting with the natural environment, it led to the genetic evolution of advantageous social behavior. Applied to nonhumans, sociobiology is noncontroversial.
Sociobiology has become one of the greatest scientific controversies of the late 20th and early 21st centuries, especially in the context of explaining human behavior. Criticism, most notably made by Richard Lewontin and Stephen Jay Gould, centers on sociobiology's contention that genes play a central role in human behavior and that variation in traits such as aggressiveness can be explained by variation in peoples' biology and is not necessarily a product of the person's social environment. Many sociobiologists, however, cite a complex relationship between nature and nurture. In response to the controversy, anthropologist John Tooby and psychologist Leda Cosmides launched evolutionary psychology as a branch of sociobiology made less controversial avoiding questions of human biodiversity.
DefinitionSociobiology is based on the idea that some behaviors (both social and individual) are at least partly inherited and can be affected by natural selection. It starts with the idea that these behaviors have evolved over time, similar to the way that physical traits are thought to have evolved. Therefore, it predicts that animals will act in ways that have proven to be evolutionarily successful over time, which can among other things result in the formation of complex social processes that have proven to be conducive to evolutionary fitness.
The discipline seeks to explain behavior as a product of natural selection, thus behavior is seen as an effort to preserve one's genes in the population. Inherent in sociobiological reasoning is the idea that certain genes or gene combinations that influence particular behavioral traits can be "passed down" from generation to generation.
Introductory exampleFor example, newly dominant male lions often will kill cubs in the pride that were not sired by them. This behavior is adaptive in evolutionary terms because killing the cubs eliminates competition for their own offspring and causes the nursing females to come into heat faster, thus allowing more of his genes to enter into the population. Sociobiologists would view this instinctual cub-killing behavior as being "passed down" through the genes of successfully reproducing male lions, whereas non-killing behavior may have "died out" as those lions were less successful in reproducing.
A genetic basis for instinctive behavioral traits among non-human species, such as in the above example, is commonly accepted among many biologists; however, attempting to use a genetic basis to explain complex behaviors in human societies has remained extremely controversial.
HistoryAccording to the OED, the word "sociobiology" was coined by John Paul Scott in 1946, at a conference on genetics and social behaviour, and became widely used after it was popularized by Edward O. Wilson in his 1975 book, . Antecedents of sociobiological thinking can be traced to the work of Robert Trivers and William D. Hamilton. Wilson's book pioneered and popularized the attempt to explain the evolutionary mechanics behind social behaviors such as altruism, aggression, and nurturence, primarily in ants (Wilson's own research specialty) but also in other animals. The final chapter of the book is devoted to sociobiological explanations of human behavior, and Wilson later wrote a Pulitzer Prize winning book, On Human Nature, that addressed human behavior specifically.
Sociobiological theorySociobiologists believe that human behavior, as well as nonhuman animal behavior, can be partly explained as the outcome of natural selection. They contend that in order fully to understand behavior, it must be analyzed in terms of evolutionary considerations.
Natural selection is considered fundamental to evolutionary theory, and asserts that hereditary traits which increase an organism's ability to survive and reproduce will be more greatly represented in subsequent generations, i.e., they will be "selected for". Thus, inherited behavioral mechanisms that allowed an organism a greater chance of surviving and/or reproducing would be more likely to survive in present organisms. Many biologists accept that inherited adaptive behaviors are present in nonhuman animal species. However, there is a great deal of controversy over the application of evolutionary models to humans both within evolutionary biology itself and the social sciences.
Sociobiology is based upon two fundamental premises:
- Certain behavioral traits are inherited,
- Inherited behavioral traits have been honed by natural selection. Therefore, these traits were probably "adaptive" in the species` evolutionarily evolved environment.
Sociobiology uses Nikolaas Tinbergen's four categories of questions and explanations of animal behavior. Two categories are at the species level; two, at the individual level. The species-level categories (often called “ultimate explanations”) are
- the function (i.e., adaptation) that a behavior serves and
- the evolutionary process (i.e., phylogeny) that resulted in this functionality.
The individual-level categories are
- the development of the individual (i.e., ontogeny) and
- the proximate mechanism (e.g., brain anatomy and hormones).
Sociobiologists are interested in how behavior can be explained logically as a result of selective pressures in the history of a species. Thus, they are often interested in instinctive, or intuitive behavior, and in explaining the similarities, rather than the differences, between cultures. For example, mothers within many species of mammals – including humans – are very protective of their offspring. Sociobiologists reason that this protective behavior likely evolved over time because it helped those individuals which had the characteristic to survive and reproduce. Over time, individuals who exhibited such protective behaviours would have had more surviving offspring than did those who did not display such behaviours, such that this parental protection would increase in frequency in the population. In this way, the social behavior is believed to have evolved in a fashion similar to other types of nonbehavioral adaptations, such as (for example) fur or the sense of smell.
Individual genetic advantage often fails to explain certain social behaviors as a result of gene-centred selection, and evolution may also act upon groups. The mechanisms responsible for group selection employ paradigms and population statistics borrowed from game theory. E.O. Wilson argued that altruistic individuals must reproduce their own altruistic genetic traits for altruism to survive. When altruists lavish their resources on non-altruists at the expense of their own kind, the altruists tend to die out and the others tend to grow. In other words, altruism is more likely to survive if altruists practice the ethic that "charity begins at home."
Within sociobiology, a social behavior is first explained as a sociobiological hypothesis by finding an evolutionarily stable strategy that matches the observed behavior. Stability of a strategy can be difficult to prove, but usually, a well-formed strategy will predict gene frequencies. The hypothesis can be supported by establishing a correlation between the gene frequencies predicted by the strategy, and those expressed in a population. Measurement of genes and gene-frequencies can be problematic, however, because a simple statistical correlation can be open to charges of circularity.
Altruism between social insects and littermates has been explained in such a way. Altruistic behavior in some animals has been correlated to the degree of genome shared between altruistic individuals. A quantitative description of infanticide by male harem-mating animals when the alpha male is displaced. Female infanticide and fetal resorption in rodents are active areas of study. In general, females with more bearing opportunities may value offspring less. Also, females may arrange bearing opportunities to maximize the food and protection from mates.
An important concept in sociobiology is that temperamental traits within a gene pool and between gene pools exist in an ecological balance. Just as an expansion of a sheep population might encourage the expansion of a wolf population, an expansion of altruistic traits within a gene pool may also encourage the expansion of individuals with dependent traits.
Sociobiology is often mistakenly associated with arguments over the "genetic" basis of intelligence. While sociobiology is predicated on the observation that genes do affect behavior, it is perfectly consistent to be a sociobiologist while arguing that measured IQ variations between individuals reflect mainly cultural or economic rather than genetic factors. However, many critics point out that the usefulness of sociobiology as an explanatory tool breaks down once a trait is so variable as to no longer be exposed to selective pressures. In order to explain aspects of human intelligence as the outcome of selective pressures, it must be demonstrated that those aspects are inherited, or genetic, but this does not necessarily imply differences among individuals: a common genetic inheritance could be shared by *all* humans, just as the genes responsible for number of limbs are shared by all individuals.
Researchers performing twin studies have argued that differences between people on behavioral traits such as creativity, extroversion and aggressiveness are between 45% to 75% due to genetic differences, and intelligence is said by some to be about 80% genetic after one matures (discussed at Intelligence quotient#Genetics vs environment). However, critics (such as the evolutionary geneticist R. C Lewontin) have highlighted serious flaws in twin studies, such as the inability of researchers to separate environmental, genetic, and dialectic effects on twins, and twin studies as a tool for determining the heritability of behavioral traits in humans have been largely abandoned.
Criminality is actively under study, but extremely controversial. There are arguments that in some environments criminal behavior might be adaptive.
ControversyThe application of sociobiology to humans was immediately controversial. Several academics opposed to Wilson's "Sociobiology" created "The Sociobiology Study Group" to counter his ideas. Many critics quickly appeared, both within evolutionary biology and outside of it. Some of the most noteworthy critics have included:
In contrast to sociobiologists, experts such as these depict nearly every human as born with a broad range of possible identities and no predispositions toward any. Human identities, including gender and race, are said to be social constructs.
Political CriticismMany critics draw an intellectual link between sociobiology and biological determinism, referring to the social Darwinism and eugenics movements of the early 20th century, and to more recent ideas such as the IQ test controversy of the early 1970s. Steven Pinker argues that critics have been overly swayed by politics and a "fear" of biological determinism. However, all these critics have claimed that sociobiology fails on scientific grounds, independent of their political critiques. In particular, Lewontin, Rose & Kamin drew a detailed distinction between the politics and history of an idea and its scientific validity, as has Stephen Jay Gould.
Wilson and his supporters counter the intellectual link by denying that Wilson had a political agenda, still less a right-wing one. They pointed out that Wilson had personally adopted a number of liberal political stances and had attracted progressive sympathy for his outspoken environmentalism. They argued that as scientists they had a duty to uncover the truth whether that was politically correct or not. They argued that sociobiology does not necessarily lead to any particular political ideology as many critics implied. Many subsequent sociobiologists, including Robert Wright, Anne Campbell, Frans de Waal and Sarah Blaffer Hrdy, have used sociobiology to argue quite separate points. Noam Chomsky came to the defense of sociobiology's methodology, noting that it was the same methodology he used in his work on linguistics. However, he roundly criticized the sociobiologists' actual conclusions about humans as lacking substance. He also noted that the anarchist Peter Kropotkin had made similar arguments in his book , although focusing more on altruism than aggression, suggesting that anarchist societies were feasible because of an inborn human nature to do good.
Wilson's defenders also claimed that the critics had greatly overstated the degree of his biological determinism. Wilson's claims that he had never meant to imply what ought to be, only what is the case are supported by his writings, which are descriptive, not prescriptive. However, many critics have pointed out that the language of sociobiology often slips from "is" to "ought", leading sociobiologists to make arguments against social reform on the basis that socially progressive societies are at odds with our innermost nature. For example, some groups have supported positions of ethnic nepotism. Views such as this, however, are often criticized as examples of the naturalistic fallacy, when reasoning jumps from descriptions about what is to prescriptions about what ought to be. (A common example is approving of all wars if scientific evidence showed warfare was part of human nature.) It has also been argued that opposition to stances considered anti-social, such as ethnic nepotism, are based on moral assumptions, not bioscientific assumptions, meaning that it is not vulnerable to being disproved by bioscientific advances. The history of this debate, and others related to it, are covered in detail by Cronin (1992), Segerstråle (2000) and Alcock (2001). Adaptationists such as Steven Pinker have also suggested that the debate has a strong ad hominem component. Some suggest that the controversy over the relative importance of various factors would be a quiet debate over subtleties if the critics were less prone to caricaturing their opponents.
CriticismsSee Evolutionary psychology controversy
See also Concepts:
Well-known sociobiologists:
Books:
External links- (Stanford Encyclopedia of Philosophy) - &
- Interviews with leading sociobiologists.
- - Richard Dawkins
- - An Attempted Sociobiological Explanation of the scientific basis for Political Group Formation.
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