Evolutionary Psychology: the Wheat the Contrary, I See Evolutionary and the Chaff Psychology As an Inevitable, Even Desirable Development Plagued by 1 Frans B.M

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to mean that it has no future. On Evolutionary Psychology: The Wheat the contrary, I see evolutionary and the Chaff psychology as an inevitable, even desirable development plagued by 1 Frans B.M. de Waal serious growing pains that need to Yerkes Primate Research Center, Emory University, Atlanta, Georgia be addressed for its own good. Looking at the social sciences as a relative outsider, I see thousands of ideas that are barely interconnected (Staats, 1991). One could ar- Abstract Few topics are as hotly debated gue that they do not need to inter- Evolutionary approaches within psychology today as evolu- connect, yet this amounts to an are on the rise in the social sci- tionary psychology. It is not that admission that every area within ences and have the potential to the issues are new—some go back the discipline is free to come up bring an all-encompassing con- to William James and the heyday with its own explanations. This ap- ceptual framework to the of social Darwinism—but evolu- proach results in a serious lack of study of human behavior. To- tionary ideas about human behav- mooring to the thinking in psychol- gether with neuroscience, ior are being forwarded with new ogy, a lack of an overarching which is digging the grave of force, backed by innovative con- scheme within which everything mind-body dualism, evolu- cepts derived from the study of an- must make sense. tionary psychology is bound to imal behavior, at a time when the A younger generation of psy- undermine the still reigning once-popular environmental and chologists, anthropologists, and human-animal dualism. If a cultural explanations are increas- even economists and political sci- Darwinian reshaping of the so- ingly recognized as inadequate. entists is gaining enthusiasm for a cial sciences seems inevitable, The stated goal of evolutionary Darwinian framework, which has even desirable, this should not psychology is to provide an evolu- the potential to tie together the for- be looked at as a hostile take- tionary account of human behav- est of hypotheses about human be- over. The underlying theme of ior. By hypothesizing about the se- havior now out there. My hope is this essay is that it is time for lection pressures that have shaped that this generation will turn evo- psychologists to join the Dar- behavior in the past, evolutionary lutionary psychology into a serious winian revolution, yet the es- psychologists expect to arrive at and rigorous science by being criti- say also critically reviews testable hypotheses about present cal of its premises without aban- current evolutionary psychol- behavior. Because evolutionary psy- doning the core idea that impor- ogy. It questions the loose ap- chology does not focus on genetic tant aspects of human behavior plication of adaptationist explanations at the exclusion of have been naturally selected. In the thinking and the fragmenta- other explanations, it is not geneti- end, evolutionary theory may serve tion of the genome, behavior, cally deterministic, even though it as the umbrella idea so desperately and the brain. From biology obviously emphasizes genetic evo- needed in the social sciences (Wil- we learn that not every spe- lution more than psychologists son, 1998). cies-typical trait is necessarily have been used to. Whereas its ob- Even though psychology is at advantageous, and from neu- jectives are broad and laudable the forefront in moving closer to roscience we learn that not ev- enough, evolutionary psychology the life sciences, it has not yet freed ery psychological ability or is unfortunately better known for a itself from certain aspects of West- tendency necessarily needs to few narrow theories about why ern philosophy, which ultimately have its own specialized brain women fall for rich guys, why step- came out of the Christian tradition. circuitry. But even if the con- fathers are not to be trusted, and Psychology is still burdened with cept of adaptation is hard to how rape is only natural. More- ancient dualisms, such as those be- apply, psychologists would do over, in the promotion of these tween body and mind, human and well to start looking at human ideas, theoretical convictions have animal, and nature and culture. It behavior in the light of evolu- often been more conspicuous than will have to rid itself of these dual- tion. data. Nonetheless, there is no way around an evolutionary approach isms before it can fully integrate with the life sciences and their non- Keywords to human behavior. Although I Christian, Aristotelian foundation. evolution; adaptation; modu- take a critical approach to evolu- Whereas we can safely leave it to larity; biology tionary psychology in this essay, my arguments should not be taken cognitive neuroscience to do away

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with any lingering mind-body du- An example straight out of the alism, and to students of animal evolutionary psychology literature— RAPE AS ADAPTATION culture to bridge the nature-culture and I could offer hundreds more— gap, psychology will also need to is found right in the opening sen- The lesson from the foregoing is get over its pervasive human-ani- tence of a recent article. It states: that one cannot atomize the organ- mal dualism. “Both male facial hair and male ism. One cannot single out a trait for pattern baldness are genetically an adaptive story, as is often done based, suggesting that they con- in evolutionary psychology. Rather, tributed to fitness” (Muscarella & one needs to (a) consider the entire DARWINISM 101 Cunningham, 1996, p. 99). Later in set of traits and (b) trace the organ- the same article, we learn that male ism’s phylogeny, that is, the ances- But before evolutionary psychol- pattern baldness may signal social tral forms that produced it. ogy can be successful, social scien- maturity, described as a friendly In moving this observation to tists will need training in evolution- kind of dominance based on wis- human behavior, it is impossible to ary theory. Many of the problems dom. Is this supposed to explain ignore the evolutionary psychol- surrounding evolutionary psychol- why we have an entire industry that ogy book that has raised most eye- ogy have nothing to do with removes hair from men’s heads? Ob- brows. In A Natural History of Rape, whether human behavior has been viously, every man wants to look Thornhill and Palmer (2000) postu- subject to evolution by natural se- mature and wise! lated that rape is an adaptation; lection—which to me is a given— The first common mistake in that is, rape may have been fa- but rather concern how broad or evolutionary explanations, then, is vored by natural selection because narrow a view of evolution one em- to think that if something is geneti- it furthered male reproduction. braces. Many followers of evolu- cally influenced it must serve a The authors extrapolated straight tionary psychology overlook some purpose. Alzheimer’s disease and from Thornhill’s insect studies, of the simplest truths coming out of cystic fibrosis have a genetic basis, which showed that there are in- evolutionary theory. as do many other diseases, but no deed species with male anatomical Dobzhansky (1973) wrote an ar- one would argue that they contrib- features that seem designed to ticle with the now-famous title ute to fitness. In addition, many force females into sexual contact. “Nothing in Biology Makes Sense characteristics are by-products of But these are flies, and in humans Except in the Light of Evolution.” others, and all that matters from an rape is part of a far larger picture. This obviously means that leaving evolutionary perspective is that the Rape occurs at the interface of sex evolution out of basic science edu- entire set of traits serves survival and power, two rich and complex cation constitutes a fatal deficiency. and reproduction. Many individ- areas of human behavior that are Because of continuing resistance to ual traits are imperfectly designed obviously interconnected. It is hard evolutionary theory, however, this or positively costly. A human ex- to see how any serious treatment of deficiency unfortunately character- ample is our back: Our species is rape can rip it from this larger con- izes large parts of the U.S. public not fully suited for an upright pos- text, explaining it as an isolated be- school system. After such an edu- ture, hence many of us suffer back havior, as Thornhill and Palmer tried cation, the young social scientist goes problems, such as hernias, slipped to do. to the university, where the curric- disks, and neck pain. Walking up- To be called an adaptation, rape ulum, with few exceptions, also ne- right must have had great benefits would need to have its own genetic glects evolutionary theory. As a re- for these costs to be tolerable, even basis separate from the genetic sult, the way evolutionary theory is though there exists no universally bases of other sexual tendencies, as applied to human behavior is often accepted theory of why we walk well as personality characteristics, riddled with curious errors. The upright. such as impulsivity or aggressivity. most basic one is taking the exist- It is no wonder that biologists of- Rape would also need to offer spe- ence of a trait to mean that it must ten refer to the evolutionary process cial reproductive advantages, and be good for something, thus ignor- as “tinkering.” Ballast often remains have been favored by selection for ing the warning of Williams (1966), visible in the end-product. Ironi- this very reason. These are heavy a contemporary evolutionary biol- cally, then, the natural world is requirements that raise a number ogist, that “adaptation is a special rampant with flawed designs that of pressing questions. Do we know and onerous concept that should reflect the trouble evolution has had if rapists are genetically unique? be used only when it is really nec- turning one form into another, such What are the advantages of rape, if essary” (pp. 4–5). as a quadruped into a biped. any, in terms of reproduction? Are

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there costs associated with rape? In table, it most certainly cannot be such preparation, as do many ani- relation to the latter question, done with the genome, the organ- mal studies, going back to the early imagine a small ancestral commu- ism, and its behavior. As for the work on imprinting, according to nity in which a man raped the brain, the current trend to divide which ducks and geese are prepro- wives and daughters of other men. brain function into modules reminds grammed to pick up information I do not think this man would have me of early ethology, when there about their species in the first days had good survival chances. And was no limit to the number of in- of life. What makes this happen is why do men sometimes rape part- stincts one could propose: from self- unclear, however, and the various ners who are perfectly willing to preservation to aggression, and labels now in use to indicate ge- engage in consensual sex? Declar- from sex to motherhood. In the netic influences on behavior—from ing rape an adaptation raises a 1950s, each species-typical tendency biogrammar, to biological algorithm, multitude of questions, questions had its own instinct, and Konrad brain module, epigenetic rule, and that Thornhill and Palmer have Lorenz’s Instinktlehre (German for learning predisposition—are re- failed to answer. “instinct doctrine”) even included a ally not much better at solving the A major problem with the strat- “parliament” of instincts to indicate mystery than the good-old instinct egy of singling out rape for evolu- how all components together influ- concept. The term module, in par- tionary explanation is that the be- ence decisions. These ideas applied ticular, carries the connotation of a havior is shown by only a small mainly to nonhuman species, but brain part that is self-contained, en- minority. The same criticism ap- human instincts have been pro- capsulated, and localized, render- plies to Daly and Wilson’s (1988) posed many times as well, most en- ing the idea unpalatable to neuro- well-known work on infanticide by ergetically by self-declared evolu- scientists (Panksepp & Panksepp, stepparents. They explained this tionary psychologist McDougall 2000). Quite possibly, our pre- category of infanticide as arising (1908). Similarly, proponents of evo- paredness for particular sets of from a lack of shared genes with lutionary psychology have compared stimuli or problems (e.g., the facil- adoptive offspring. I would argue the brain to a Swiss army knife to ity with which we recognize faces; that in seeking to understand rare which evolution has one by one Gauthier & Tarr, 1997) boils down behavior we should never ignore added modules for everything to learned stimulus relevance the norm. If child abuse by step- from face recognition, to tool use, rather than specialized brain cir- fathers is evolutionarily explained, preference for kin over nonkin, cuitry. why do so many more stepfathers child care, friendship, detection of Williams (1966) was right to lovingly care for their children cheaters, and theory of mind2 warn that adaptation is an onerous than abuse them? And if rape is (Tooby & Cosmides, 1992). concept that should be applied par- such an advantageous reproduc- One problem with this ap- simoniously. What evolutionary psy- tive strategy, why are there so proach—apart from the fact that chology needs to develop is a taste many more men who do not rape brain modules at any specific task for multilevel thinking in which at- than who do? I have called this the level have yet to be demonstrated— tention freely shifts between imme- dilemma of the rarely exercised op- is that this would make for an in- diate (proximate) explanations of tion: A Darwinian account of an credibly unwieldy brain, much like behavior, which are the traditional atypical behavioral choice is in- a computer to which a new chip domain of psychology, and evolu- complete without at least an would need to be added each time tionary (ultimate) explanations. In equally good account of the typical we install another program: one other words, it needs to address choice (de Waal, 2000). chip for word processing, one for both the “how” questions of how games, one for spreadsheets, and things work and the “why” ques- so on. Instead, a computer is a mul- tions of why evolution favored a tipurpose device that allows each particular behavior—to put a little THE MODULE EXPLOSION application to draw on its full po- less evolution and a little more tential. psychology into its explanations. Followers of evolutionary psy- This is not to imply that the chology often talk about a gene for brain is a tabula rasa. It seems pre- this or a brain module for that, pared to acquire certain skills more seeking to dissect the whole to ex- easily than others, and to be wait- CONCLUSION plain each part separately. If this ing for certain kinds of informa- cannot be done with the compo- tion. The studies by Tooby and Current problems with evolu- nents of a watch spread out on the Cosmides (1992) do indeed suggest tionary psychology may be serious,

190 VOLUME 11, NUMBER 6, DECEMBER 2002 but they are not insurmountable. adopting. They derive from scien- 1982/1998, 1996). Because evolu- Evolutionary psychology is bound tists, such as Darwin, who first of tionary explanations require close to overcome them. I dare predict all were naturalists. If evolutionary attention to phylogeny, and given that 50 years from now every psy- psychology embraces Edward Wil- that primatologists are used to be- chology department will have Dar- son it cannot help but get covered havioral complexity not unlike that win’s bearded portrait on the wall. in ants, and if it embraces William of our own species, evolutionary Evolutionary approaches have the Hamilton it cannot overlook the psychology and primatology make potential to introduce a conceptual beetles and parasites that fasci- natural partners. framework that will accommodate nated this brilliant biologist. With The questions asked by evolu- or replace the current proliferation regard to animals closer to us, the tionary psychology may strike of disconnected theories in the parallels are even more striking. some readers as simplistic, yet they study of human behavior. Chimpanzees, for example, en- are here to stay. Questions about Even though evolutionary psy- gage in political alliances when why we choose particular mates, chology, like the rest of psychol- jockeying for power, show empa- avoid incest, and favor kin, and ogy, oftentimes acts as if the hu- thy toward others in distress, es- what modes of cooperation we en- man species is a world apart, it tablish an economy of services and gage in, for example, are not the cannot help but undermine its own favors, and reconcile with oppo- traditional questions of psychol- anthropocentrism given the source nents after a fight by means of a ogy, yet they emerge naturally of the theories that it is so eagerly kiss and embrace (Fig. 1; de Waal, from an evolutionary perspective.

Fig. 1. Example of chimpanzees’ use of eye contact and hand gestures to invite a reconciliation. This photograph shows the situa- tion 10 min after a protracted, noisy conflict between two adult males at the Arnhem Zoo in the Netherlands. The challenged male (left) fled into the tree, but 10 min later his opponent stretched out a hand. Within seconds, the two males had a physical reunion and climbed down together to groom each other on the ground. Photograph by the author.

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These basic questions are central to more: Johns Hopkins University Press. (Origi- the transcript of my 2001 Focus on Sci- nal work published 1982) any evolutionary approach. Psy- ence Plenary Address, which was pre- sented at the annual meeting of the de Waal, F.B.M. (2000, April 2). Survival of the chologists who do not like the sim- rapist [Review of the book A natural history of American Psychological Association in plicity of the answers currently rape: Biological bases of sexual coercion]. New York San Francisco and was on the topic of this Times Book Review, pp. 24–25. coming out of evolutionary psy- essay. I am also grateful to Mauricio Pap- Dobzhansky, T. (1973). Nothing in biology makes chology should make an effort to ini and Scott Lilienfeld for comments on sense except in the light of evolution. American previous versions of the manuscript. improve them, to broaden its intel- Biology Teacher, 35, 125–129. Gauthier, I., & Tarr, M.J. (1997). Becoming a “Gree- lectual horizon, because all of psy- ble” expert: Exploring mechanisms for face chology would stand to gain from recognition. Vision Research, 37, 1673–1682. a more enlightened evolutionary McDougall, W. (1908). An introduction to social psy- Notes psychology. chology. New York: Putnam. Muscarella, F., & Cunningham, M.R. (1996). The 1. Address correspondence to Frans evolutionary significance and social percep- Recommended Reading B.M. de Waal, Living Links, Yerkes Pri- tion of male pattern baldness and facial hair. mate Research Center, Emory Univer- Ethology & Sociobiology, 17, 99–117. de Waal, F.B.M. (1999). The end of sity, 954 N. Gatewood Rd., Atlanta, GA Panksepp, J., & Panksepp, J.B. (2000). The seven 30322. sins of evolutionary psychology. Evolution and nature versus nurture. Scientific Cognition, 6, 108–131. 2. Theory of mind means that one American, 281, 94–99. Staats, A.W. (1991). Unified positivism and unifi- de Waal, F.B.M. (2001). The ape and understands the mental states of others cation psychology: Fad or new field? American the sushi master: Cultural reflections (a capacity that may be limited to hu- Psychologist, 46, 899–912. by a primatologist. New York: Basic mans and apes). Thornhill, R., & Palmer, C.T. (2000). A natural his- Books. tory of rape: Biological bases of sexual coercion. Mayr, E. (2001). What evolution is. Cambridge, MA: MIT Press. New York: Basic Books. Tooby, J., & Cosmides, L. (1992). The psychologi- Evolution: The tri- cal foundations of culture. In J. Barkow, L. Zimmer, C. (2001). References Cosmides, & J. Tooby (Eds.), The adapted mind: umph of an idea. New York: Harper Evolutionary psychology and the generation of cul- Collins. Daly, M., & Wilson, M. (1988). Homicide. Haw- ture (pp. 19–136). New York: Oxford Univer- thorne, NY: Aldine de Gruyter. sity Press. de Waal, F.B.M. (1996). Good natured: The origins of Williams, G. (1966). Adaptation and natural selection. Acknowledgments—I thank Allison right and wrong in humans and other animals. Princeton, NJ: Princeton University Press. Berger and Virginia Holt for providing Cambridge, MA: Harvard University Press. Wilson, E.O. (1998). Consilience: The unity of knowl- de Waal, F.B.M. (1998). Chimpanzee politics. Balti- edge. New York: Knopf.

Mutually Responsive Orientation dinal beneficial effects of MRO for early development of con- Between Mothers and Their Young science have been replicated across studies, for a broad range Children: A Context for the Early of developmental periods from Development of Conscience infancy through early school 1 age, and using a wide variety of Grazyna Kochanska behavioral, emotional, and cog- Department of Psychology, University of Iowa, Iowa City, Iowa nitive measures of conscience in the laboratory, at home, and in school. These findings highlight the importance of the early par- Abstract development of conscience in ent-child relationship for subse- Some parent-child dyads es- young children. Children grow- quent moral development. tablish a mutually responsive ing up with parents who are re- orientation (MRO), a relation- sponsive to their needs and ship that is close, mutually whose interactions are infused Keywords binding, cooperative, and af- with happy emotions adopt a relationships; mutuality; con- fectively positive. Such rela- willing, responsive stance to- science tionships have two main ward parental influence and be- characteristics—mutual re- come eager to embrace parental How do young children become sponsiveness and shared posi- values and standards for behav- aware of rules, values, and standards tive affect—and they foster the ior. The concurrent and longitu- of behavior accepted within their