OPINION ARTICLE published: 08 March 2010 doi: 10.3389/fpsyg.2010.00003 Grand challenges of evolutionary psychology

Robert Kurzban*

Department of Psychology, University of Pennsylvania, Philadelphia, PA, USA *Correspondence: [email protected]

What we’ve got here is a failure to communicate the insights from evolutionary psychology have been advancing an Eighteenth century, to those outside the fi eld. pre-enlightenment notion that there is “Cool Hand Luke,” 1967 Taking an evolutionary approach has such a thing as “mental energy;” psychol- elicited hostility from audiences since the ogy’s own phlogiston (c.f., Van den Berg, SHARED CHALLENGES fi eld’s inception. The story has frequently 1986). This idea is absurd in the context Researchers in evolutionary psychology face been told of the pitcher of water dumped of the computational theory of mind, but the same grand challenges as researchers on E.O. Wilson’s head at a meeting for the its absurdity does not seem to have slowed who eschew the evolutionary approach in American Association for the Advancement the pace of publication. From this, it can their own fi elds of study. Why, and when, do of Science in 1978 (Segerstråle, 2000). be inferred that ideas in psychology, even if people behave altruistically? How do peo- This incident can be seen in retrospect they are fundamentally incompatible with ple make decisions, economic or otherwise, as a harbinger of things to come. While known facts, don’t arouse such skepticism as and what role do emotions play in decision- the water pitcher has been replaced by the long as the idea don’t derive from a systematic making? How do people choose their mates? written word, the level of discourse has not analysis of evolved function. How do people acquire information, from always improved. In addition to the politi- Daly and Wilson (2007) suggest that basic physical knowledge about objects and cal attacks on the fi eld, whether from the critics of the fi eld “are not just skeptical, forces to important local knowledge about left or the right (Segerstråle, 2000; Pinker, they are angry” (p. 396), and that the skepti- particular people and artifacts? How do 2002), the scientifi c attacks are so strong cism of their research agenda “appears to be these processes differ from – or resemble – that they include the charge that evolu- motivated by something other than a hum- learning processes among non-humans? tionary psychology isn’t even a science ble search for the truth” (p. 390). Critics’ How do the answers to all of these questions (Tattersall, 2001). anger translates into practices that ought depend on properties of the individual, such Indeed, antipathy for the view that doing to evoke scientifi c outrage. To take just one as sex, life history phase, genetic endow- psychology can be improved with the idea of many possible examples, Thornhill and ment, developmental history, and context? of evolved function has spawned an array of Palmer (2000) wrote that “whether rape is And what are the physiological and neuro- articles and books with more or less provoc- an adaption or byproduct cannot yet be physiological substrates of the mechanisms ative titles, including allusions to the “Sins defi nitively answered” (p. 84), but their that underlie all of these processes? of Evolutionary Psychology” (Panksepp position has been consistently portrayed Evolutionary psychologists share these and Panksepp, 2000), a collection of as the opposite, as Lloyd’s (2001) claim that challenges with researchers from other dis- Arguments Against Evolutionary Psychology they “begin by assuming that rape is a single ciplines because the fi eld is not, of course, (Rose and Rose, 2000), Richardson’s (2007) trait, and that this trait is an adaptation” (p. distinguished from others in terms of the Evolutionary Psychology as Maladapted 1542, emphasis original). A decade on, edi- domain of inquiry. Evolutionary psychol- Psychology, and so on. tors continue to allow authors to perpetuate ogists study economic decision making Antagonism to the fi eld takes the form of this misrepresentation: Leiter and Weisberg (like economists), interpersonal and group a deep skepticism about work that derives (2010, p. 72) recently did so, ironically dynamics (like social psychologists), cul- from its principles. Kenrick et al. (2005) enough in the context of taking another tural processes (like anthropologists), and report an anecdote in which a textbook author to task for misrepresentation1. endocrine effects (like physiologists). author found that reviewers insisted he The questions evolutionary psycholo- present criticisms of evolutionary research, THE CHALLENGE OF THE CHALLENGES gists ask are not only our questions, and but not of non-evolutionary research backed Debate and discussion are, of course, all the methodological hurdles we must over- by less evidence. Conway and Schaller to the good. Confl ict helps distill truth, come are faced by our colleagues with non- (2002) made similar observations, suggest- as champions make their cases for their evolutionary approaches because we share ing that it is in the context of evolutionary favored proposition, allowing their views the same toolkit, from ethnography to ideas that have consistently been subjected to be judged by observers. behavioral lab studies to neuroimaging. to and resisted falsifi cation “that charges of What, then, are the challenges uniquely nonfalsifi ability and other declarations of 1This paper gave me an unusual opportunity to inte- ract personally and directly with critics because one of faced by evolutionary psychology? disbelief are most often aired” (p. 154). the authors (DW) is at my institution, the University Indeed, the skepticism faced by evolu- of Pennsylvania, and because both authors presented UNIQUE CHALLENGES tionary psychological hypotheses is stun- the paper at a colloquium series at Penn’s Law School. I would argue that perhaps the fi eld’s greatest ning set against the credulousness with In February of 2007, well before publication, I pointed out various errors in the manuscript, including this challenge lies less is coaxing nature to give which other ideas are greeted. Baumeister misrepresentation. The authors chose not to make up her secrets, and more in communicating and colleagues (e.g., Baumeister et al., 2007) corrections.

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The challenge faced by evolutionary psy- in the non-human animal literature (Alcock, Instead of challenging ideas and hypotheses, chology, however, is that the critics do not 2001); however, this productive framing of critics challenge assumptions and commit- participate in this dialectic. Interlocutors discussions can only occur after the relevant ments no one holds. engaging with evolutionary psychologists scholars have fully understood the logic of This suggests that the real challenge frequently don’t engage with evolutionary adaptationism and its role in hypothesis for evolutionary psychology is to get oth- psychology, preferring instead to fabricate construction and testing (Cosmides and ers to challenge them on scientifi c grounds. evolutionary psychologists’ views, and then Tooby, 1997). People who disagree with evolutionary attack the imagined positions (see Kurzban, Secondly, critics routinely and inces- psychologists are welcome; competition 2002). santly – and incorrectly – assert and insist and considered debate will only make the Why is this the case? At this point it is that evolutionary psychology is genetic fi eld better. unclear. A recent survey potentially illus- determinist, from Gould (1983), to the Having said that, and in stark contrast, trates one aspect of the problem. Park present day (Quartz and Sejnowski, 2002; challenging the just-so story-telling ghouls (2007) investigated 10 social psychology Lickliter and Honeycutt, 2003; Smith and and genetic determinist ghosts so many hal- texts’ presentation of Hamilton’s (1964) Thelen, 2003). This is emphatically not lucinate helps no one. theory of kin selection. This is a good test the position of evolutionary psychology, As long as disagreements are honest, case because kin selection is central to mod- as has been made clear any number of respectful, and about genuine points of ern evolutionary biology and directly rel- times (Symons, 1992, p. 140; Tooby and confl ict, there really is only one challenge evant to human social behavior (family and Cosmides, 1992; Dennett, 1995, p. 338; that matters: explaining human behavior. altruism), and, at least in its broad strokes, Pinker, 1997, p. 33). is not particularly diffi cult to master, deriv- This short piece is not the place to won- REFERENCES ing from one inequality with three terms der why the central animating idea of the Alcock, J. (2001). The Triumph of Sociobiology. < Cambridge, MA, Oxford University Press. (C rB). Park reviewed 10 texts. Of the 10, fi eld – that the components of the mind Baumeister, R. F., Vohs, K. D., and Tice, D. M. (2007). 0 got it right. As Park put it: “Rather than have functions – is taken to mean that The strength model of self-control. Curr. Dir. Psychol. presenting purely scientifi c theories of evo- development occurs without any infl u- Sci. 16, 351–355. lution and kin selection, many textbooks ence of the environment. Alcock (2001) Carroll, G. (Producer), and Rosenberg, S. (Director). seemed to be presenting a mixture of the- remarked that “the myth of the determinist (1967). Cool Hand Luke [Motion Picture]. United States, Warner Brothers. ory and intuition” (p. 868). If kin selection sociobiologist has been carried forward by Conway, L. G. III, and Schaller, M. (2002). On the veri- cannot be conveyed at an undergraduate some opponents who avoid acknowledging fi ability of evolutionary psychological theories: an textbook level, it is perhaps not surprising even in passing the long history of rebuttal analysis of the psychology of scientifi c persuasion. that more complex ideas have not been suf- to this caricature. Why? Because the genetic Pers. Soc. Psychol. Rev. 6, 152–166. fi ciently well understood by the fi eld’s critics determinist is too convenient a strawman Cosmides, L., and Tooby, J. (1997). Dissecting the compu- tational architecture of social inference mechanisms. to enable them to engage properly. to be discarded” (p. 44). In Characterizing Human Psychological Adaptations Indeed, two areas of confusion that stand A singular challenge is to make progress (Ciba Foundation Symposium #208). Chichester, out. The fi rst area is adaptationism (Williams, despite the fact that critics do not appear to Wiley, pp. 132–156. 1966). As many people have explained, adap- have any interest in discarding this conven- Daly, M., and Wilson, M. (2007). Is the “Cinderella effect” controversial? A case study of evolution-minded tationism links evidence and hypotheses, ient strawman. research and critiques thereof. In Foundations of relating observations – behavior, morphol- Evolutionary Psychology, C. Crawford and D. Krebs, ogy, etc. – to hypotheses of evolved function MOVING FORWARD eds (Mahwah, NJ, Erlbaum). (e.g., Tooby and Cosmides, 1992). The fail- The key challenge evolutionary psycholo- Dennett, D. (1995). Darwin’s Dangerous Idea: Evolution ure to understand the logic of adaptation- gists face is how to interact with the sci- and the Meanings of Life. New York, NY, Simon & Schuster. ism – about how hypotheses about function entifi c community in a way that does not Gould, S. J. (1983). Hen’s Teeth and Horse’s Toes. require evidence of design – probably gives elicit the usual errors described above. This New York, Norton & Co. rise to worries about “just-so story-telling” is not, of course, to say that evolutionary Gould, S. J. (1997). Evolution: the pleasures of pluralism. (Gould, 1997) and related worries about psychologists are always right or that any New York Rev. Books 44, 47–52. epistemology (see Ketelaar and Ellis, 2000). given functional hypothesis will turn out Hamilton, W. D. (1964). The genetical evolution of social behaviour I and II. J. Theor. Biol. 7, 1–16; Similarly, many critics continue to think, to be correct. Evolutionary psychologists, 17–52. perhaps misled by the word “evolutionary” like other social scientists – or any scien- Kenrick, D. T., Maner, J. K., and Li, N. P. (2005). in the fi eld’s moniker, that evolutionary tists for that matter – are obviously going Evolutionary social psychology. In The Handbook psychologists’ hypotheses are about phylog- to be wrong with great frequency. Favored of Evolutionary Psychology, D. Buss, ed. (Hoboken, eny, or evolutionary history (e.g., Leiter and hypotheses will turn out to be incorrect, NJ, Wiley), pp. 803–827. Ketelaar, T., and Ellis, B. J. (2000). Are evolutionary expla- Weisberg, 2010, pp. 38–39). Because the logic errors in reasoning will become clear, and nations unfalsifi able? Evolutionary psychology and of adaptationism is central to the discipline, lines of research will have to be reevaluated the Lakatosian philosophy of science. Psychol. Inq. critics’ failures to understand it represents a and abandoned. 11, 1–21. signifi cant impediment to progress. As things currently stand, however, the Kurzban, R. (2002). Alas poor evolutionary psychology: unfairly accused, unjustly condemned. [Review of Indeed, substantial progress will have typical process of correction is retarded Alas Poor Darwin: Arguments against Evolutionary been made when debates focus on putative because interlocutors with evolutionary Psychology edited by H. Rose and S. Rose]. Hum. 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Leiter, B., and Weisberg, M. (2010). Why evolutionary Richardson, R. C. (2007). Evolutionary Psychology as eds (New York, NY, Oxford University Press), biology is (so far) irrelevant to legal regulation. Law Maladapted Psychology. Cambridge, MA, MIT Press. pp. 19–136. Philos. 29, 31–74. Rose, H., and Rose, S. (2000). Alas poor Darwin: Van den Berg, C. J. (1986). On the relation between Lickliter, R., and Honeycutt, H. (2003). Developmental Arguments Against Evolutionary Psychology. New energy transformation in the brain and mental dynamics: toward a biologically plausible evolution- York, NY, Harmony Books. activities. In Energetics and Human Information ary psychology. Psychol. Bull. 129, 819–835. Segerstråle, I. (2000). Defenders of the Truth: The Battle Processing, R. Hockey, A. Gaillard and M. Coles, eds Lloyd, E. (2001). Science gone astray: evolution and rape. for Science in the Sociobiology Debate and Beyond. (Dordrecht, The Netherlands, Martinus Nijhoff), Mich. Law Rev. 99, 1536–1559. New York, NY, Oxford University Press. pp. 131–135). Panksepp, J., and Panksepp, J. B. (2000). The seven Smith, L., and Thelen, E. (2003). Development as a Williams, G. C. (1966). Adaptation and Natural Selection. sins of evolutionary psychology. Evol. Cogn. 6, dynamic system. Trends Cogn. Sci. 7, 343–348. Princeton, NJ, Princeton University Press. 108–131. Symons, D. (1992). On the use and misuse of Darwinism Park, J. H. (2007). Persistent misunderstandings of inclu- in the study of human behavior. In The Adapted Mind, Received: 19 January 2010; accepted: 03 February 2010; sive fi tness and kin selection: their ubiquitous appear- J. Barkow, L. Cosmides and J. Tooby, eds (New York, published online: 08 March 2010. ance in social psychology textbooks. Evol. Psychol. 5, NY, Oxford University Press), pp. 137–159. Citation: Kurzban R (2010) Grand challenges of evolu- 860–873. Tattersall, I. (2001). Evolution, genes, and behavior. Zygon tionary psychology. Front. Psychology 1:3. doi: 10.3389/ Pinker, S. (1997). How the Mind Works. New York, NY, 36, 657–666. fpsyg.2010.00003 W. W. Norton & Company. Thornhill, R., and Palmer, C. (2000). A Natural History of This article was submitted to Frontiers in Evolutionary Pinker, S. (2002). The Blank Slate: The Modern Denial Rape: Biological Bases of Sexual Coercion. Cambridge, Psychology, a specialty of Frontiers in Psychology. of Human Nature. New York, NY, Viking. MA, MIT Press. Copyright © 2010 Kurzban. This is an open-access article Quartz, S., and Sejnowski, T. J. (2002). Liars, Lovers and Tooby, J., and Cosmides, L. (1992). The psychologi- subject to an exclusive license agreement between the authors Heroes: What the New Brain Science Has Revealed cal foundations of culture. In The Adapted mind: and the Frontiers Research Foundation, which permits unre- About How We Become Who We Are. New York, NY, Evolutionary Psychology and the Generation stricted use, distribution, and reproduction in any medium, Harper-Collins. of Culture, J. Barkow, L. Cosmides and J. Tooby, provided the original authors and source are credited.

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