In evolutionary psychology, the psychological aspects of the human mind and human behavior are explained from the point of view of evolution theory. Psychological functions such as memory, attention, perception and language, but also human characteristics and behaviors such as empathy, altruism, choice of partner, leadership, and intergroup conflict are considered from the perspective of natural selection.
For example, people can remember a lot of faces. Face recognition offers advantages because it enables people to remember with which person they have shared what information and with which person they have which type of relationship. In human evolution the social groups became larger and it was therefore advantageous to be able to distinguish many human faces. Because facial recognition offers a selection advantage, we can assume that it is an evolutionary adaptation (adaptation).
For example, there was a certain degree of selfishness and impulsivity, but also empathy, helpfulness and self-control (if shown under the right conditions) certain selection advantages. Evolutionary psychologists therefore assume that qualities such as empathy and helpfulness are also adaptations.
The theories and findings of evolutionary psychology apply to many areas such as economics, health, management, environment, law, psychiatry, politics and literature.
History and theoretical foundations
The theories on which evolutionary psychology is based are derived from the work of Charles Darwin who discovered a mechanism, natural selection, through which species could develop and new species could emerge. Evolutionary psychology makes use of the progress in the knowledge of the theory of evolution from evolutionary biology.
Evolutionary psychologists assume that natural selection has also led to psychological adjustments, in the same way that natural selection also leads to anatomical and physiological adjustments. As with adjustments in general, psychological adaptations are specialized for the environment in which an organism evolved, the environment of evolutionary adaptability or the EEA (environment of evolutionary adaptedness). Natural selection ensures that organisms adapt to their environment. Sexual(and social) selection ensures that organisms adapt to their social environment in finding a sexual partner. Sexual selection gives rise to sex differences. Because women make a relatively larger parental investment than men (just like all other mammals), they are pickier than men in the choice of a sexual partner. This prediction from evolutionary psychology has been demonstrated many times.
Another milestone in the development of evolutionary psychology is the inclusive fitness theory of William Donald Hamilton, first put forward in 1964. Hamilton showed with a mathematical model that individuals can strengthen the distribution of their genes in the next generation by helping close relatives with whom they share their genes and to reproduce. According to the “rule of Hamilton”, altruism can develop. Other theories for explaining the evolution of altruistic behavior are reciprocity, reputation, punishment, and (cultural) group selection. These theories explain not only the evolution of altruism but also of qualities such as empathy, guilt, anger, and loyalty.
An important concept in evolutionary psychology is the EEA of environment of evolutionary adaptedness. This term, introduced by the British psychiatrist and psychoanalyst John Bowlby (1907-1990), describes the environmental factors in which a certain behavior has evolved in an evolutionary way through adaptations and under pressure from natural selection. Since people often change the environment so quickly that the brain can not adapt quickly enough, there can be a mismatch in which adaptive behavior in our ancestral environment is no longer adaptive (for example the fear of snakes and spiders and strangers).
Other important theories used by evolutionary psychology are: the life history theory of Erik Erikson, the theory of parental investment theory, the costly signaling theory of Amotz Zahavi, the indirect reciprocity theory and the cultural group selection theory.
Evolutionary psychology is based on a number of essential assumptions:
- The human brain is an information-processing organ, and directs behavior in response to external and internal stimuli.
- The adaptive mechanisms that make up the brain are formed by natural selection.
- Different neural mechanisms specialize in solving various problems in the evolutionary past of man.
- The human psyche consists of many specialized mechanisms, each of which is sensitive to different types of information. These mechanisms produce certain types of behaviors that are generally adaptive, that is, they increase the survival chances and reproductive success of the individual.
Evolutionary psychology has established itself as a scientific movement and has an increasingly strong influence on psychology itself, both in the United States and in Europe. Evolutionary psychologists regard their field of research not so much as a subdiscipline within psychology, but they assume that the theory of evolution can offer a fundamental, meta-theoretic framework that integrates the directions within psychology as well as biology and anthropology. Within the related fields, biological psychology social psychology anthropology and neurology, principles derived from the theory of evolution have gained a greater weight during the last 20 years.
The development of the human brain is an important area of attention for evolutionary psychology. For example, functions such as consciousness, language, intelligence and empathy can be associated with the more developed frontal lobes, the larger brain volume and the stronger lateralization of the human brain compared to the brains of other mammals. The growth of the neocortex in human evolution is attributed to the need to live in ever larger groups. Important influential representatives of this direction are Michael Corballis, Robin Dunbar and Steven Pinker.
Methods of Research
An evolutionary psychologist observes contemporary behavior and then tries to explain how and under which (environmental) factors this behavior could have arisen (evolving). For example: the psychologist observes that people cheat. Then he tries to think (and investigate) whether cheating could have been an evolutionary advantage. If cheating has indeed been beneficial for the reproductive chances of the individual, then selection will have been on this property. That may be the reason why we are still cheating today.
Evolutionary psychologists use various research methods to test their predictions, including behavioral experiments, cognitive experiments, neuroscience research, questionnaires, research among hunter-gatherers, cross-cultural research, medical research, archaeological research, and computer simulations.
Evolutionary psychologists assume that behaviors or properties that are common in all cultures are good candidates for evolutionary adaptations. Examples of potentially evolved characteristics are: emotions, perception of faces, empathy, discrimination between relatives and non-relatives, and cooperation with others. Evolutionary psychologists make theoretical predictions from the theory of evolution about various types of human characteristics and behaviors such as altruism, intelligence, leadership, personality, preference for sexual partners, perception of beauty, parental investment that often come true.
Controversies about evolutionary psychology often focus on questions about the testability of hypotheses, the theoretical assumptions (such as the modular functioning of the brain, and the uncertainty about the nature of the ancestral environment), the importance of non-adaptive cultural explanations, but also political and ethical issues as a result of the interpretations of some research results.