Criticism of Evolutionary Psychology
Evolutionary Psychology makes use of a biologically informed approach (modern evolutionary perspective) to examine human behavior as well psychological traits like language, perception and memory. Specifically, Evolutionary Psychology has the primary objective of identifying which human psychological traits can be attributed to natural selection. Buss (1999) points that cognitive psychology is similar to Evolutionary Psychology in the sense that they both agree that human behavior is linked to internal psychological mechanisms; the only difference is that evolutionary psychologists propose that the internal psychological mechanisms are adaptations. According to Rose & Rose (2000), adaptationist thinking is the main focus of Evolutionary Psychology, in the sense that it makes use of the principles applied in evolutionary biology. In this regard, evolutionary psychologists maintain that the modular structure of the human mind is the same as that of the body, wherein different modular adaptations serve various functions. As a result, Evolutionary Psychology holds that most elements of human behavior are attributed to psychological adaptations, which evolved with the aim of solving the recurring problems faced by human ancestors in their environments (Workman & Reader, 2004). Despite the adaptationist approach being the cornerstone of Evolutionary Psychology, it has drawn significant criticism, especially basing on the fact that Evolutionary Psychology is inherently biased towards adaptationism. This paper reviews the criticism of Evolutionary Psychology with regard to its adaptationist perspective and evaluates whether this Evolutionary Psychology can overcome this critique or whether Evolutionary Psychology is doomed to fail.
Evolutionary Psychology makes use of the theoretical perspectives outlined in evolutionary biology to have an understanding of the design of the human mind. Ryle (2005) asserts that the influence of Evolutionary Psychology has grown significantly in the last 20 years, especially among behavioral scientists as well the public. However, many people are of the view that the core assumptions of Evolutionary Psychology are somewhat extraordinary and radical. According to Workman & Reader (2004), Evolutionary Psychology perceives the human brain to be comprised of mainly adaptations. The fundamental precept help by Evolutionary Psychology is that natural selection resulted in both morphological adaptations as well as psychological adaptations, which are common among human beings. In the light of this view, adaptation refers to a mechanism that helped in solving a specific problem linked to reproduction and survival during the ancestral past (Wilson, Dietrich, & Clark, 2003).
According to the principles of evolutionary biology, functionally specialized adaptation occurred for all types of organismal tissues found in living things. For instance, consider the organs found in the human torso, wherein the heart has the main function of pumping blood, the intestines take out nutrients from digested food, and the human liver filters blood among others. It is evident that adaptation in the human body is domain specific, in the sense that it does extremely well in its individual function; however, it might be less helpful for other tasks. For instance, the pancreas does a good job in hormone production such as insulin, but is not useful in other tasks such as processing oxygen. Similar patterns of observations can be derived for any form of adaptation in the various species (Rose & Rose, 2000). The underlying argument is that, functionally specialized adaptation is the universal and default evolutionary design standard. In this regard, all that Evolutionary Psychology does is to make use of the default position, in the sense that it holds the assumption that the default and universal evolutionary design principle can be applied to the human brain, just like the case of other tissues found in species (Ryle, 2005). Despite the fact these might appear an extraordinary assumption to individuals who are not used to the idea that brain is also a product of evolution, there is no doubt that this is an ordinary assumption when viewed from the adaptationist perspective of evolutionary biology. In the last 20-25 years, evolutionary psychologists have gathered substantial evidence to affirm that their assumptions are indeed correct. Rose & Rose (2000) asserts that this evidence points out that there are individuals with specialized psychological adaptations; for example the selection of reproductive partners in numerous contexts; spotting and administering punishment to cheaters especially in cooperative scenarios; recognition of well-known human faces; selecting non-toxic and nutritive food; and avoiding disease among others. In addition, whereas each of the adaptations is exceptional in tackling problems associated with a particular domain, there are less helpful in other domains. For instance, none of the aforementioned adaptations would be principally helpful in other domains such as empathizing with peers, running away from non-human predators, or staying away from high-fall places (Wilson, Dietrich, & Clark, 2003).
It is also imperative to acknowledge that, in contrast with the common critique of adaptationism in Evolutionary Psychology, the adaptationist evolutionary biology, which is the basis of Evolutionary Psychology, does not presuppose that all traits are as a result of adaptations (Buss, 1999). The assumption held by the adaptationist evolutionary biology is that most of the traits tend be non-adaptive; as a result, it is particularly interested in identifying the traits that are derivatives of adaptations. For instance, it is highly likely that nipples in males have no individual function; however, they exist as a derivative of selection for nipples found in females. Workman & Reader (2004) stresses that, the primary objective of the adaptationist evolutionary biology, since the inception of “adaptationist program” during the 1960s, has always been, and still is, to openly provide the criteria that would enable scientists differentiate adaptive traits from non-adaptive traits.
Critics of adaptationism in Evolutionary Psychology always argue that Evolutionary Psychology has not produced experiments that can be used to differentiate likely adaptive bases of human behavior from evolutionary mechanisms that are likely to be non-adaptive. According to Gould & Lewontin (1979), Evolutionary Psychology is different from other human behavior theories such as cognitive psychology, in the sense that it argues that some mental traits are somewhat adaptive. According to critics, in evolutionary biology, a number of non-adaptive mechanisms that enable evolution to generate the behaviors observed in people today. For example, besides natural selection, other processes can alter gene frequencies and create novel traits. A case in point is genetic drift, which is defined as the random effects attributed to chance variation in the environment, genes or development. According to Gould & Lewontin (1979), evolutionary derivatives refer to traits not specifically designed to perform an adaptive function; nonetheless, they may benefit the organism and are perhaps species-typical. When describing traits that bring no adaptive advantage to the organism but are likely to be transferred by the adaptive trait, Gould & Lewontin (1979) invented the phrase “spandrel” and not some of form adaptation as maintained by evolutionary psychologists maintain. According to Gould & Lewontin (1979), helpful psychological traits are not likely to be adaptations rather exaptations, which the authors define as traits that developed for either other purposes or no functional roles at all, after which they were co-opted to suit their current roles. Exaptations can be of two forms, which include co-opted adaptation and a spandrel. Co-adaptation refers to a trait that developed as a form of adaptation for a single purpose, although they were utilized for another adaptive role. As a result, Gould & Lewontin (1979) suggested that cognition in human beings could be explained by the “spandrel”, in the sense that natural selection increased the size of the human brain; however, most of the mental properties of human beings are spandrels (non-adaptive side effects associated with developing structural complexity of such a magnitude). After a trait that has been acquired using other mechanisms results in adaptive advantage (as claimed by evolutionary psychologists that the mental properties of human beings do), then Gould & Lewontin (1979) point out that it is open to additional selection as a form of an “exaptation”. In this regard, critics of adaptationism in Evolutionary Psychology maintain that adaptive significance of the mental properties that are examined by evolutionary psychologists has not been affirmed. In addition, critics assert that the manifestation of such traits cannot be linked to natural selection.
There are a number of problems associated with Gould & Lewontin’s (1979) criticisms. First, evolutionary psychologists perceive adaptations as a form of psychological phenomena, which are considered the main faculties of the human mind. Gould & Lewontin (1979) argue that the primary form of psychological adaptation in human beings relates to the size of the brain. However, there was no adaptive advantage associated with the largeness of the brain by itself. As Buss (1999) illustrates, the sheer bulk of the human brain is perhaps disadvantageous. If anything is to be considered a by-product or derivative, then it must be the brain size of humans since it consumes most of the body’s nutrients; for instance, the brain takes up 18 percent of the energy intake despite being only 2 percent of the total body weight (Ryle, 2005). In addition, the human brain makes people highly vulnerable to falls and blows, and increases the hazards incurred during childbirth. Evidently, it can be argued that the bulkiness of the brain is perhaps a derivative of the selection process for more complex and computational abilities; this enabled human ancestors to deal with the natural world, hand bog tools and deal with one another. Therefore, the critics’ assertion regarding what constitutes a psychological adaptation, used to differentiate by-products from adaptations, can be argued to be getting things backwards. This is because the capacities facilitated by a larger brain size are considered some form of adaptation because the selection served to address these capabilities whereas the sheer brain size can be considered a derivative for the selection process for these capabilities.
Fundamentally, it is evident that Evolutionary Psychology attempts to highlight the selected-for capacities associated with an enlarging brain size. In this regard, Wilson, Dietrich, & Clark (2003) asserts that Evolutionary Psychology appears faultless. Certainly, it does mean that each of the psychological mechanisms outlined in Evolutionary Psychology is in fact a form of adaptation. In addition, this does not mean that Evolutionary Psychology has accurately recognized any of the existing psychological mechanisms. Simply stated, Workman & Reader, (2004) asserts there is adequate room for Evolutionary Psychology to be erroneous with regard to the psychological mechanisms that make up the human mind and be erroneous with respect to the evolutionary history of a particular psychological mechanism correctly identified by evolutionary psychologists. According to Ryle (2005), it is likely that the criticisms of adaptationism in Evolutionary Psychology may be closer to the truth when compared with Evolutionary Psychology; however, the closeness to the truth cannot be based on the reasons cited by these critics such as Gould. It is evident that there are relatively fewer psychological adaptations than the claim made by evolutionary psychologists, and that many of the adaptations advocated for evolutionary psychologists are derivatives or by-products of psychological adaptations; however, if Evolutionary Psychology is deemed to be wrong in this way, Workman & Reader (2004) asserts that this faults in Evolutionary Psychology cannot be attributed to the search for psychological adaptations, but as a result of Evolutionary Psychology failing to correctly recognize these psychological adaptations. As Ryle (2005) maintains, critics of adaptationism in Evolutionary Psychology tend to mischaracterize the field of Evolutionary Psychology, and that empirical research in Evolutionary Psychology is designed with the main aim of identifying the adaptive and non-adaptive psychological traits. Perhaps, at the moment, evolutionary psychologists have not correctly identified one, but they will in future.
In conclusion, it is evident from the above discussion that the criticism of adaptationism Evolutionary Psychology can be overcome and that the success of Evolutionary Psychology research program is imminent. There is no doubt that the principles of Evolutionary Psychology are similar to the evolutionary biological perspectives. This simply means that, if you accept that natural selection is the only framework that can be used to explain function in biology, then, you are embracing the concept of Evolutionary Psychology. Recognizing that the evolution of the brain took place through natural selection is the first towards understanding what aspects of human mental properties can be linked to natural selection. In addition, empirical research in Evolutionary Psychology is designed with the main aim of identifying the adaptive and non-adaptive psychological traits. Perhaps, at the moment, evolutionary psychologists have not correctly identified one, but they will in future.
Buss, D. (1999). Evolutionary Psychology: The New Science of the Mind. Boston: Allyn and Bacon.
Gould, S. J., & Lewontin, R. C. (1979). The Spandrels of San Marco and the Panglossian Paradigm: A Critique of the Adaptationist Programme. Proceedings of the Royal Society of London , 581-598.
Rose, H., & Rose, S. (2000). Alas, Poor Darwin: Arguments against Evolutionary Psychology. New York: Harmony Books.
Ryle, A. (2005). The Relevance of Evolutionary Psychology for Psychotherapy. British Journal of Psychotherapy , 21 (3), 375–88.
Wilson, D. S., Dietrich, E., & Clark, A. B. (2003). On the inappropriate use of the naturalistic fallacy in evolutionary psychology. Biology and Philosophy , 18 (5), B669–681.
Workman, L., & Reader, W. (2004). Evolutionary psychology: an introduction. Cambridge : Cambridge University Press.