Population evolutionary psychology provides broad claims about human nature and culture for popular consumption. Just as natural selection has caused morphological adaptations, Pop EP has allowed for universal human nature adaptations such as face recognition, parental care, and mate attraction and retention. However, there are many faults within population EP. The largest fallacy is a lack of evidence from the conditions under which early human evolution occurred and therefore, a lack of evidence of the evolution of our ancestors’ psychological traits. For example, in order to discover why language evolved, one would need to identify the adaptive purposes it served among extinct hominins. But little evidence of these purposes exists. In addition, because features of the physical and social environments create a selective response on species’ motivational and cognitive processes, we would need to be able to precisely identify the adaptive problems and understand how preexisting traits were modified. However, we don’t have enough knowledge of our ancestors’ psychological traits to determine how selection affected the traits in order to form modern human minds.
Evidence that would support whether a trait has occurred or is occurring would be found using the comparative method. Nevertheless, the comparative method with our closest living relatives during the past six million years, the chimpanzee and the bonobo, would be futile with human traits. These relatives do not possess forms of the complex psychological human traits like language. If there was a way to compare the lifestyle of more closely related species with shared cognitive abilities, evidence could possibly be strong enough to support the claims within Pop EP. The time scale would take place over centuries to see the effects of adaptive problems and the psychological selection that occurs within the human mind.
For more information on the fallacies of pop evolutionary psychology, see Buller, D. J. 2009. “Four Fallacies of Pop Evolutionary Psychology.” Scientific American 300: 74-81.