The history of evolutionary psychology began with Charles Darwin, who said that humans have social instincts that evolved by natural selection. Darwin’s work inspired later psychologists such as William James and Sigmund Freud but for most of the 20th century psychologists focused more on behaviorism and proximate explanations for human behavior.
E. O. Wilson’s landmark 1975 book, Sociobiology, synthesized recent theoretical advances in evolutionary theory to explain social behavior in animals, including humans. Jerome Barkow, Leda Cosmides and John Tooby popularized the term “evolutionary psychology” in their 1992 book The Adapted Mind: Evolutionary Psychology and The Generation of Culture. Like sociobiology before it, evolutionary psychology has been embroiled in controversy, but evolutionary psychologists see their field as gaining increased acceptance overall.
After his seminal work in developing theories of natural selection, Charles Darwin devoted much of his final years to the study of animal emotions and psychology. He wrote two books;The Descent of Man, and Selection in Relation to Sex in 1871 and The Expression of the Emotions in Man and Animals in 1872 that dealt with topics related to evolutionary psychology.
He introduced the concepts of sexual selection to explain the presence of animal structures that seemed unrelated to survival, such as the peacock’s tail. He also introduced theories concerning group selection and kin selection to explain altruism. Darwin pondered why humans and animals were often generous to their group members.
Darwin felt that acts of generosity decreased the fitness of generous individuals. This fact contradicted natural selection which favored the fittest individual.
Darwin concluded that while generosity decreased the fitness of individuals, generosity would increase the fitness of a group. In this case, altruism arose due to competition between groups. The following quote, from Darwin’s Origin of Species, is often interpreted by evolutionary psychologists as indication of his foreshadowing the emergence of the field:
“In the distant future I see open fields for far more important researches. Psychology will be based on a new foundation, that of the necessary acquirement of each mental power and capacity by gradation.”
— Darwin, Charles (1859). The Origin of Species.
Darwin’s theory inspired William James’s functionalist approach to psychology. At the core of his theory was a system of instincts. James wrote that humans had many instincts, even more than other animals. These instincts, he said, could be overridden by experience and by each other, as many of the instincts were actually in conflict with each other.
In their Evolutionary Psychology Primer, Tooby and Cosmides make note of James’ perspective, and also quote him:
“We do not realize that ‘normal’ behavior needs to be explained at all. This “instinct blindness” makes the study of psychology difficult. To get past this problem, James suggested that we try to make the “natural seem strange”:
“It takes…a mind debauched by learning to carry the process of making the natural seem strange, so far as to ask for the why of any instinctive human act. To the metaphysician alone can such questions occur as: Why do we smile, when pleased, and not scowl? Why are we unable to talk to a crowd as we talk to a single friend? Why does a particular maiden turn our wits so upside-down? The common man can only say, Of course we smile, of course our heart palpitates at the sight of the crowd, of course we love the maiden, that beautiful soul clad in that perfect form, so palpably and flagrantly made for all eternity to be loved!
And so, probably, does each animal feel about the particular things it tends to do in the presence of particular objects. … To the lion it is the lioness which is made to be loved; to the bear, the she-bear. To the broody hen the notion would probably seem monstrous that there should be a creature in the world to whom a nestful of eggs was not the utterly fascinating and precious and never-to-be-too-much-sat-upon object which it is to her.
Thus we may be sure that, however mysterious some animals’ instincts may appear to us, our instincts will appear no less mysterious to them”.
-(William James, 1890)
According to Noam Chomsky, perhaps Anarchist thinker Peter Kropotkin could be credited as having founded evolutionary psychology, when in his 1902 book Mutual Aid: A Factor of Evolution he argued that the human instinct for cooperation and mutual aid could be seen as stemming from evolutionary adaption.
William McDougall made a reference to “evolutionary psychology” in his 1919 book An Introduction to Social Psychology:
“It is only a comparative and evolutionary psychology that can provide the needed basis (for psychology); and this could not be created before the work of Darwin had convinced men of the continuity of human with animal evolution as regards all bodily characters, and had prepared the way for the quickly following recognition of the similar continuity of man’s mental evolution with that of the animal world.” (p. 16)
Post World War II
While Darwin’s theories on natural selection gained acceptance in the early part of the 20th century, his theories on evolutionary psychology were largely ignored. Only after the second world war, in the 1950s, did interest increase in the systematic study of animal behavior. It was during this period that the modern field of ethology emerged. Konrad Lorenz and Nikolaas Tinbergen were pioneers in developing the theoretical framework for ethology for which they would receive a Nobel prize in 1973.
Desmond Morris’s book The Naked Ape attempted to frame human behavior in the context of evolution, but his explanations failed to convince academics because they were based on a teleological (goal-oriented) understanding of evolution. For example, he said that the pair bond evolved so that men who were out hunting could trust that their mates back home were not having sex with other males.
In 1975, E. O. Wilson built upon the works of Lorenz and Tinbergen by combining studies of animal behavior, social behavior and evolutionary theory in his book Sociobiology:The New Synthesis. Wilson included a chapter on human behavior. Wilson’s application of evolutionary analysis to human behavior caused bitter debate.
With the publication of Sociobiology, evolutionary thinking for the first time had an identifiable presence in the field of psychology. E. O. Wilson argues that the field of evolutionary psychology is essentially the same as “human sociobiology”.
Edward H. Hagen writes in The Handbook of Evolutionary Psychology that sociobiology is, despite the public controversy regarding the applications to humans, one of the scientific triumphs of the twentieth century:
“Sociobiology is now part of the core research and curriculum of virtually all biology departments, and it is a foundation of the work of almost all field biologists”
Sociobiological research on nonhuman organisms has increased dramatically and appears continuously in the world’s top scientific journals such as Nature and Science. The more general term behavioral ecology is commonly used as substitute for the term sociobiology in order to avoid the public controversy. Shermer (2004). The Science of Good and Evil. Henry Holt and Co. ISBN 978-0-8050-7769-8