Two Tenure-Track Jobs – ASU

I’m happy to pass along the following job ad: 

Job Vacancy Announcement

Two Assistant Professors, Evolutionary Anthropology 

The School of Human Evolution and Social Change at Arizona State University seeks to fill two positions in evolutionary anthropology at the assistant professor level, reflecting our continuing investment in global leadership in the area of evolutionary social science. Minimum qualifications include a Ph.D. in hand at time of appointment in anthropology, psychology, or a closely-related field, and a strong record of empirical or theoretical research.

Desired qualifications include (1) research that focuses on the evolution of modern behavior, especially within the areas of evolutionary psychology, gene-culture coevolution, mathematical evolutionary theory, and the evolution of technology, or (2) research that focuses on the evolutionary basis of social behavior or cognition in nonhuman primates, especially as related to aspects of social complexity.

Additional desirable qualifications include evidence of or potential for obtaining external funding; teaching experience in anthropology or related fields; commitment to mentoring and supporting students; and collaborative experience with interdisciplinary research projects. Anticipated start date August 2014.

We will begin reviewing applicants on November 15, 2013. Reviews may occur every two weeks thereafter until the search is closed.  Applicants must apply online at and include a letter of application, curriculum vitae, and the names and email addresses of three references. Please make sure your last name appears in each uploaded file name. You may address your cover letter to Professor Joan Silk, Evolutionary Anthropology Search Committee Chair. ASU Job ID: 10547.

Information about the School can be found at  The School is a world leader in anthropology research and training (including in evolutionary anthropology) and transdisciplinary social science. We collaborate extensively with ASU’s Institute for Human Origins (  A background check is required for employment. Arizona State University is an equal opportunity/affirmative action employer. Women and minorities are encouraged to apply. See

04. November 2013 by kurzbanepblog
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Postdoc Available — Aarhus

A postdoc position is open at The Politics and Evolution (PoNE) Lab at the Department of Political Science and Government, Aarhus University in Denmark.

The PoNE Lab is dedicated to the investigation of the psychological and biological influences on political decisions. The open position is related to a project on the role of cognitive biases in the processing of political communication. The project seeks to utilize laboratory methods and cross-national surveys for studying whether, how, when and for whom political communication that appeals to evolved, cognitive biases is persuasive.

The full announcement of the position can be found at the following URL:

28. October 2013 by kurzbanepblog
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On the Uses of Moral Dumbfounding

A piece in the Opinionator of the New York Times by Amia Srinivasan on Sunday addresses a perennial debate in philosophy that is increasingly at the focus of modern political debates.

I’m interested in one particular (small) move she makes in the course of her lengthy piece, so you’ll have to bear with me.

Srinivasan opens with the debate between John Rawls and Robert Nozick. Simplifying greatly, should the state redistribute wealth from rich to poor (Rawls) or just enforce contracts (Nozick)? In the modern discourse, this plays out as, again simplifying greatly, as the heartless money-grubbing Rand-loving capitalist pigs on the right versus the pinko welfare queen coddling Marx-loving commies on the left.

She uses a series of questions to invite the reader to think about the virtues of free markets, claiming that “If you’re going to buy Nozick’s argument, you must say yes to all four.” Here is the first one, followed by her comment on the question

1. Is any exchange between two people in the absence of direct physical compulsion by one party against the other (or the threat thereof) necessarily free?

If you say yes, then you think that people can never be coerced into action by circumstances that do not involve the direct physical compulsion of another person. Suppose a woman and her children are starving, and the only way she can feed her family, apart from theft, is to prostitute herself or to sell her organs. Since she undertakes these acts of exchange not because of direct physical coercion by another, but only because she is compelled by hunger and a lack of alternatives, they are free.

What struck me was her choice of the two options the hypothetical woman had to save the starving children. She chose transactions that were both illegal and, more interestingly, banned for reasons that psychologists can’t quite puzzle out.

I’ve spent a fair bit of time trying to work out both of those cases. They seem to follow the pattern that Jon Haidt famously discussed in the context of sibling incest. People more or less uniformly judge consensual (enjoyable, non-reproductive) incest to be morally wrong, but are unable to supply reasons for their view. Haidt termed this “moral dumbfounding.”

As I say, I’ve spent some time trying to figure out prostitution and organ-selling. Both are banned in most parts of the world, and most people in my casual conversations on the topic think that these transactions are morally wrong. I and some of my students and collaborators have even gathered some data on the prostitution issue. We never published anything on it, but the short story from the data is that people are weird about this. Most of our subjects say that if John and Susan are married, and John says he’ll mow the lawn if and only if Susan has sex with him, this within-marriage sale of sexuality is still morally wrong.

Srinivasan could have chosen legal ways that the hypothetical mother could earn money. But she didn’t. What if she had written, “Suppose a woman and her children are starving, and the only way she can feed her family, apart from theft, is to take a job flipping burgers.” Would readers be led as strongly away from the Nosickian view? My guess is that Srinivasan thought that such a hypothetical wouldn’t strike the reader as wrong, and so be less effective. (For what it’s worth, a world in which unskilled labor has only those two options would result fairly quickly in driving down the wages in both cases. The hypothetical is a bit unstable.)

There’s also the matter of the relationship between the hypothetical and the question Srinivasan is after. Recall that the question was, “Is any exchange between two people in the absence of direct physical compulsion by one party against the other (or the threat thereof) necessarily free?” Is the fact that we find prostitution and organ-selling morally wrong, even repugnant, relevant to the question of whether the character was free versus coerced? Staunch Nozickians would probably resist conceding that point; we might not like the world in which people have only such choices, they might say, but that doesn’t mean that the choices weren’t freely made. (If one were to be entirely draconian about it, one might say that she has the option of letting her family starve. I presume there are few if any occupants of that Nozickian pole.)

(I’m also not sure if Srinivasen has in mind a world in which prostitution and organ-selling are legal or illegal. If the state (effectively) bans prostitution, and we take freedom to mean something along the lines of people having more rather than fewer choices, then it seems to me that the state has reduced her choice set, and so coerced her into some other choice, possibly letting her family starve.)

It’s worth noting that Srinivasen doesn’t feel much better about burger-flipping than prostitution, lamenting that “there is certainly no prohibition against the mind-numbing and often humiliating menial work that poor people do in exchange for paltry wages from hugely rich companies.” Given her dim view of the fast food industry, it’s a bit more surprising this example didn’t feature in the question she posed. Further, if the issue is about coercion, then it seems worthwhile to ask who is doing the coercion in the burger-flipping case. If Burger Prince offers her a low wage – offering her a choice that she did not have before the wage was offered –  has the firm coerced her? The coercing entity would seem to have to lie elsewhere.

None of this, of course, answers the psychological puzzle of the origin of the moral intuitions regarding prostitution and organ-selling. When I discuss this with people, I get various answers, but most of them don’t address the key point. In both cases, it’s just fine to give the good or service in question away. Therefore, the right answer can’t be something like, “well, organ transplants are disgusting.” We’re perfectly fine letting people have a doctor take people’s organs out as long as no money changes hands. The answer would seem to have to have something to do with adding money to the transaction. And it doesn’t seem like the answer can be something along the lines of how unpleasant it is and how only poor people will X if it is legal. Again, burger-flipping cases indicate that we’re happy to tolerate, as a society, a whole array of soul-crushing jobs. There seems to be something else happening that needs some extra explanatory oomph. I have one thought on this topic – he added mysteriously – but haven’t run the right studies yet. And, I should add, I’m happy to hear people’s views

I’ll let Srinivasen have the last word, which I actually liked because of her attention to the notion of moral consistency, which some of us worry about quite a bit:

Rejecting the Nozickian worldview requires us to reflect on what justice really demands, rather than accepting the conventional wisdom that the market can take care of morality for us. If you remain a steadfast Nozickian, you have the option of biting the bullet (as philosophers like to say) and embracing the counterintuitive implications of your view. This would be at least more consistent than what we have today: an ideology that parades as moral common sense.

22. October 2013 by kurzbanepblog
Categories: Blog | 3 comments

Of Course Religious Communities Cooperate. But Maybe…

Religion is puzzling.

Religion – at least the organized religions with which people in the West are familiar – cause people to do odd things, such as adopt (or, at least, appear to adopt) a large number of false beliefs, engage in rituals that are at best useless and at worst costly, and give up their resources to strangers.

Probably because these things all seem strange from an evolutionary point of view, scholars have spilled considerable ink trying to explain religion, both its component parts (supernatural belief, costly ritual) and the whole enchilada. Book length treatments include, in no particular order, Religion Explained (Boyer), The Belief Instinct (Bering), The God Delusion (Dawkins), Breaking the Spell (Dennett), and Darwin’s Cathedral (Wilson).

Arguably the predominant argument surrounding religion goes something like this. People with religious beliefs are less likely than people without religious beliefs to lie, cheat, steal, or mix dairy with meat because they are afraid of supernatural punishment. Doing less of (at least the first three of) these things is good for the individual — because supernatural-agent-believing-in people get punished less than they otherwise would for breaking rules – and for the group – because there is less welfare-destroying behavior than there would be if people didn’t believe in punitive gods.

Of course a link exists between religion and cooperation, if only insofar as members of organized Western religions really do tend to cooperate with their co-religionists. Members of religious organization cooperate in any number of ways, of course, from bake sales to fund renovations of the nave to cooperative child care to going on Crusades.

And there are data supporting a link between religion and cooperation using various techniques. For example, some have investigated the issue by looking at individual differences. Atkinson and Bourrat (2011), for instance, looked at people’s self-reported religious beliefs and their self-reported endorsement of a number of items relating to morality. (For instance, people’s views on whether lying is never, sometimes, or always justified.) They conclude:

The results we present here are consistent with and provide support for specific predictions of the supernatural monitoring and fear of supernatural punishment hypotheses. As predicted by both theories and consistent with our Hypothesis 1, individuals who professed belief in God rated moral transgressions as less justifiable than those who did not. Consistent with Hypothesis 2 and the supernatural punishment hypothesis, stronger beliefs about the unjustifiability of moral transgressions were present in individuals who professed belief in heaven or hell. And consistent with Hypothesis 3 and the supernatural monitoring hypothesis, among those who believe in God, those who professed belief in a personal God rated moral transgressions as less justifiable than those who professed belief in a Spirit or Life Force.

But maybe the cooperative face of religion isn’t the whole story, or even the main story. After all, people organize themselves into all kinds of cooperative groups that have few features of organized religions (supernatural beliefs, rituals, etc.). Perhaps people organize themselves into religious groups for some other reason and then, by virtue of finding shared interests, cooperate toward common goals.

A new paper now in press in Evolution and Human Behavior by #cough# Jason Weeden and Robert Kurzban with the laconic title, “What predicts religiosity? A multinational analysis of reproductive and cooperative morals” diverges from the dominant religion-is-for-cooperation view.

We used the same database that Atkinson and Bourrat used, but our interest was in the possibility that people used religious organizations less as a locus of cooperation, generally, but more as a means of advancing their reproductive goals. Previous work showed strong relationships between religious variables such as church attendance and planned church attendance with self-reported sexual behavior and attitudes, such as sociosexuality – i.e., roughly, promiscuity – and moral views on stuff pertaining to sex and reproduction, such as views on abortion, birth control, and pre-marital sex. So, we looked at the relationships among religiosity, reproductive morals, and cooperative morals drawing on the vast amount of data available from many nations in the World Values Survey.

As one might have guessed, both the cooperative items and the reproductive items correlate reasonably well with the religious items. Still, just looking at these relationships, we find that, internationally, the relationship between cooperative morals and religious items was about one quarter of the size of the relationship between reproductive morals and religious items.

Though this suggests to us that the reproductive issues might be driving participation in religion, in themselves these relationship don’t settle much because both accounts of religion allow, in principle, for other relationships to exist. One could imagine that religion was for cooperating, but then once cooperative religious groups form, they take on systematic properties, such as moralizing sexual behavior. So, the next step is to run analyses in which we regress religiosity measures on both the reproductive items and the cooperative morals items. When we ran these analyses, we found that the coefficients on the relationship between reproductive morals and religion stayed about the same but the coefficients on the relationship between cooperative morals and religion were mostly eliminated, in some cases becoming slightly negative. This pattern existed, with variations on the theme, worldwide.

In short, while there is, for sure, a relationship between cooperative morals and religiosity, this relationship is attenuated or eliminated when controlling for reproductive morals, and this attenuation occurs pretty much everywhere we have looked.

This is not to say, of course, that various aspects of religion might not have evolved because of their role in facilitating cooperation. I myself am skeptical of such accounts for a number of reasons, not the least of which is that, for reasons I’ve discussed before, natural selection should punish systems that give rise to false beliefs about supernatural punishment in favor of systems that give rise to true beliefs. Still, these patterns of data suggest to us that people might be joining religion because of religion’s role in facilitating their favored reproductive strategy.

So of course religious groups cooperate, and often do so effectively and successfully. But maybe people join religious groups for reasons that go beyond cooperation per se, having more to do with the role religion plays in people’s sexual and reproductive behavior.

07. October 2013 by kurzbanepblog
Categories: Blog | 14 comments

Two Penn Job Ads

Some readers of this blog might know people interested in these two job openings at my home institution, the University of Pennsylvania, or know people who might be.

JOB AD #1 

The School of Arts and Sciences at the University of Pennsylvania seeks to add to the faculty of our newly formed Evolution Cluster. We invite applicants for a tenure-track assistant professor appointment in evolution, broadly interpreted. We are interested in exceptional scientists who will establish a research program to empirically study the evolution of dynamical processes using field or laboratory experiments or the construction and analysis of massive data sets.  Areas of interest include, but are not limited to: the evolution of neural, social, ecological or linguistic dynamics and networks; evolution of early life or exobiology; biochemical, neuronal, or cooperative interactions and exchange of information at the molecular, cellular, human, or ecosystems scales; directed evolution of organisms or processes; analyzing extant structures and networks, from molecules to populations, along with their evolutionary trajectories, including the development of new modalities to extract data from the geologic, genetic, or linguistic historical records. The successful candidate’s primary appointment will be in a single department in the natural sciences: Biology, Chemistry, Earth and Environmental Science, Linguistics, Mathematics, Physics and Astronomy, or Psychology.   Secondary appointments in other departments can be arranged, as appropriate.   The successful candidate will have a strong interest in building a program that generates interaction with researchers from other disciplines who are working within the overarching theme of evolution and will teach courses in his or her home department and participate in the development of curricula pertinent to the Evolution Cluster (See for more information).  The University of Pennsylvania is an Affirmative Action/Equal Opportunity Employer and is strongly committed to establishing a diverse faculty:

Applications should be submitted on-line at and include a curriculum vitae, a research statement that includes the candidate’s perspective on how she or he fits into one of the core departments, links to no more than three journal publications, and the contact information for three individuals who will provide letters of recommendation. Review of applications will begin 1 November 2013 and will continue until the position is filled.


THE DEPARTMENT OF PSYCHOLOGY, UNIVERSITY OF PENNSYLVANIA, in collaboration with Penn’s undergraduate program in Philosophy, Politics, and Economics (PPE) invites applications for a tenure-track assistant professor in the area of Behavioral Decision Making. Our primary focus is at the junior, Assistant Professor level, but we will consider candidates at the level of Associate Professor without tenure. The Department of Psychology is strongly committed to Penn’s Action Plan for Faculty Diversity and Excellence and to establishing a diverse faculty (for more information see:   Applicants should have an active, high quality, research program that includes experimental research in areas relevant to Psychology and PPE.  Such areas include, but are not limited to, social norms, fairness, trust, cooperation, and moral judgment.  This position provides the opportunity to interact across multiple disciplines with Penn faculty who are interested in these research areas. Candidates should have a commitment to teaching excellence at both the graduate and undergraduate levels.  Our undergraduate teaching priorities include a course in experimental methodology and a course in behavioral psychology and economics. These courses will target PPE majors and be cross-listed in Psychology. Applications should be submitted on-line at:

and include a CV, statements of research and teaching interests, and the names of three referees whom we may contact for an appraisal. Review of applications will begin November 1, 2013 and will continue until the position is filled. The University of Pennsylvania is an Affirmative Action/Equal Opportunity Employer.

01. October 2013 by kurzbanepblog
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Is Evolutionary Psychology WEIRD or NORMAL?

Joe Henrich and colleagues’ paper, The weirdest people in the world, argued that psychology draws too much on WEIRD (Western, Educated, Industrialized, Rich, and Democratic) samples. This work has received, with excellent reason, a tremendous amount of attention.

Recently, I’ve been hearing this critique specifically about evolutionary psychology. Back in March, for instance, one prominent blogger made the following claim:

One of the common complaints about evolutionary psychology is that it claims to be addressing evolved human universals, but when you look at the data sets, they are almost always drawn from the same tiny pool of outliers, Western undergraduate students enrolled in psychology programs, and excessively extrapolated to be representative of Homo sapiens — when we’re actually a very peculiar group.

(Note that the blogger in question correctly pointed out in a comment to the post (#8) that while his post singled out evolutionary psychology, the paper by Henrich et al. did not focus specifically on the field.)

In any case, given that this is a “common complaint” – to take one more example, Kate Clancy implied that using non-WEIRD samples was one way to “make progress in evolutionary psychology” – I thought it would be worthwhile to check the claim by the blogger, namely that data sets in evolutionary psychology are “almost always” from WEIRD samples.

Before I do, it’s important to keep things in perspective. There are large numbers of social scientists who are in the business of trying to understand and explain human nature but do not take an explicitly evolutionary approach. Authors of textbooks in social psychology, for instance, when they are discussing their topic of inquiry, don’t indicate an interest in a particular subset of humanity – the undergraduates at the institutions where these scholars work – but rather they indicate that they have broader ambitions, understanding human behavior.

For instance – all bold font is my emphasis – according to Gilovich, Keltner, and Nisbett (2011), “Social psychologists go beyond folk wisdom and try to establish a scientific basis for understanding human behavior by conducting studies and setting up experiments” (pp. 7). Aronson, Wilson, and Akert (2010) define social psychology as “the scientific study of the way in which people’s thoughts, feelings, and behaviors are influenced by the real or imagined presence of other people” (pp. 3). Baumeister and Bushman (2011) pose the question, “Can social psychology help us make sense of the bizarre and baffling diversity of human behavior?” (p. 3) and answer their own question with a (“resounding”) “Yes!” Wikipedia seems to agree, indicating that “social psychology is the scientific study of how people‘s thoughts, feelings, and behaviors are influenced by the actual, imagined, or implied presence of others.” Similar remarks are made in other social psychology textbooks.

These quotations make clear that social psychologists are interested in humans, people, broadly, rather than just undergraduates at top American research institutions. This explicit focus is important because it places on equal footing the ambitions of evolutionary social scientists and non-evolutionary social scientists. Both are interested in the full panoply of human behavior, especially social behavior, both features that are universal and those that vary across populations. For this reason, social psychology provides a good comparison class. Are researchers in evolutionary psychology more or less likely to draw on non-WEIRD samples?

To address this question, I surveyed the 2012 volume of the top journal in social psychology, The Journal of Personality and Social Psychology (JPSP) and the official journal of the Human Behavior and Evolution Society, Evolution and Human Behavior (E&HB). (And by “I surveyed” of course I mean that other people did all the work. Hat tip: Fatima Aboul-Seoud and Molly Elson.) For each empirical paper, we scored whether the samples used were exclusively WEIRD, both WEIRD and non-WEIRD, or exclusively non-WEIRD. The results are in the Figure below.

Fig. 1. WEIRDness in two journals.

Fig. 1. WEIRDness in two journals.

Roughly 96% of the papers in JPSP, designed to “make sense of the bizarre and baffling diversity of human behavior,” came from WEIRD samples. This figure was 65% for E&HB. (A chi square on these values is hugely significant.)

Still, is two thirds enough? Should it be more? Perhaps.

Scholars collect convenience samples from undergraduates (and other WEIRDos) because they are, well, convenient. Is convenience a good reason? Maybe not, but tradeoffs are. Gathering data from the field is difficult, a fact known by no one so well as Joe Henrich, who organized the cross-cultural project in behavioral economics. Part of what made that work so valuable – conducting Dictator Games and Public Goods games, etc., in numerous small-scale societies – was that there was an array of (conveniently and cheaply gathered) data to compare it to. The Hadza Dictator Game offers (25%) wouldn’t seem so weird without the WEIRD comparison offers (~50%).

Gathering data from such small-scale societies as the Hadza requires a lot more time and effort per datum than it does among American undergraduates, making convenience samples not just convenient, but efficient. Given that there is a limited pie of social science resources – research time and granting agency funding –  efficiency matters.

In some fields of psychology, gathering such data would be prohibitively expensive. My colleague Coren Apicella, who works with the Hadza, has a difficult enough time getting sufficient supplies to conduct her work (and stay alive) as it is; bringing in an fMRI machine to the shores of Lake Eyasi would be essentially impossible. Similarly, vision scientists rely nearly exclusively on samples from nearby, in no small part because of the equipment needed to for their studies. Of course, there is also the belief that their results will generalize easily to the rest of the population, but it’s worth bearing in mind that one of the examples Henrich et al. point to where results don’t generalize was in the visual domain, the Müller-Lyer illusion.

To return to the quotation with which I opened, unless two thirds of the time means the same thing as “almost always,” the (undocumented) claim by the popular blogger above is false, but the suggestion (p. 22) made by Henrich et al. seems about right:

More than other researchers in the social sciences, evolutionary researchers have led the way in performing systematic comparative work, drawing data from diverse societies. This is not because they are interested in variation per se (though some are), but because they are compelled, through some combination of their scientific drive and the enthusiasm of their critics, to test their hypotheses in diverse populations.

In sum, as measured by this analysis of samples in articles in journals, adding evolution to psychology makes the science less WEIRD, and more NORMAL (Non-Weird Organisms Resembling Mankind’s Ancestral Lifestyle, with apologies for the stretch as well as the gendered language, which I needed for the “M”). Should the social sciences be less weird still? Perhaps. I certainly hope our colleagues over at journals such as JPSP start taking the point about non-WEIRD samples as seriously as we do in the evolutionary community.


Aronson, E., Wilson, T. D., & Akert, R. M. (2010). Social psychology (7th ed.). Upper Saddle River, NJ: Pearson Education, Inc.

Baumeister, R. F., & Bushman, B. J. (2011). Social psychology and human nature (2nd ed.). Belmont, CA: Wadsworth, Cengage Learning.

Gilovich, T., Keltner, D., & Nisbett, R. E. (2011). Social psychology (2nd ed.). New York, NY: W. W. Norton & Company, Inc.

Henrich, J., Heine, S. J. & Norenzayan. A.  (2010). The weirdest people in the world? Behavioral and Brain Sciences 33 (2-3):61-83.

25. September 2013 by kurzbanepblog
Categories: Blog | 17 comments

How Do Biologists Support Functional Claims?

The press has reported extensively on a new (and frickin’ cool) paper out in Science documenting gears on the back legs of a little insect (Issus). Ed Yong over at National Geographic has a piece on this work, including embedding the little movie of the gears in action, which is, as I say, 100% totally and completely cool.

594px-Issus.coleoptratus.nymph.with.Dryininae.larvaBecause the press has covered this work, I’m not going to talk about the work per se.

Rather, I want to address an issue which I’ve discussed from time to time, which is how biologists draw inferences about function. What kinds of evidence do they use when they make a claim that a particular structure is for something?

I’m not interested in this for purely philosophical reasons regarding the epistemic commitments of biologists as a general matter.

I’m interested in this because of critiques regarding functional claims made in the context of evolutionary psychology. In particular, critics have made various suggestions about what sort of evidence is used by biologists to make claims regarding function, suggesting that similar sorts of evidence ought to be used when evolutionary psychologists make claims about function.

So, how do Burrows and Sutton, the authors of the paper in question – “Interacting Gears Synchronize Propulsive Leg Movements in a Jumping Insect” – provide evidence for their claim?

First of all, note the functional claim in the title. The crucial word there is “synchronize.” The function of the bits of the body in question – the little gears – are to synchronize the legs. If the legs weren’t in synchrony, then the insect’s jump would be asymmetric, and the insect would tilt to the left or right instead of jumping straight ahead. (I watched some videos of frogs jumping, and it looks to me that frogs use asymmetrical leg motions to (intentionally?) get some yaw into their jumps. Anyone know anything about that?)

Second, note the evidence that they present. Figure 1(D) is a picture, showing the interlocking gears. Figure 1(E) is a diagram of the gears. The Supplemental Material includes a series of movies. These materials also indicate the methods used: mostly making the movies and taking the photographs. The authors are not shy about their conclusions, writing:

The mechanical gears in Issus enhance the synchrony between leg movements to the level of microseconds…The gears in Issus… demonstrate that mechanisms previously thought only to be used in manmade machines have evolved in nature. Nymphal planthoppers have interacting gears that play an essential functional role in a natural behavior.

To be clear, then, the authors infer the function – synchronization of the legs, which in turn allows for jumping without any yaw – from the images. The shape of the structures they found, together with the behavior they observe, affords the inference regarding function. This is because those particular shapes – interlocking gears – are complex elements of the phenotype that are improbably well designed to execute the function in question, synchronization. As George Williams articulated so well in Adaptation and Natural Selection, functional complexity is the hallmark of adaptation. It’s worth quoting Williams, who specifically discussed cases like the one in the present paper, in which there is an analog with human artifacts:

A frequently helpful but not infallible rule is to recognize adaptation in organic systems that show a clear analogy with human implements. There are convincing analogies between bird wings and airship  wings, between bridge suspensions and skeletal suspensions, between the vascularization of a leaf and  the water supply of a city. In all such examples, conscious human goals have an analogy in the biological  goal of survival, and similar problems are often resolved by similar mechanisms. Such analogies may  forcefully occur to a physiologist at the beginning of  an investigation of a structure or process and provide  a continuing source of fruitful hypotheses. At other  times the purpose of a mechanism may not be apparent initially, and the search for the goal becomes  a motivation for further study. Adaptation is assumed  in such cases, not on the basis of a demonstrable  appropriateness of the means to the end but on the indirect evidence of complexity and constancy.

In short, both Williams and the present authors infer function from form. But note that there are important dogs that don’t bark here. The authors don’t provide any data regarding the genetics of the structures in question. They don’t provide any data regarding heritability. There aren’t any experiments. And that’s just fine. The point is that the shapes are themselves the evidence. The rows of teeth, interlocking as they do, provide compelling evidence for the function of synchronization.

Is there room for doubt? Of course. I find myself persuaded, but I suppose it’s possible that these teeth arose as a side-effect of some other aspect of the phenotype. That possibility seems wildly unlikely to me, but I suppose it could be. Or maybe the gears are actually some sort of sense organ. Again, that seems wildly improbably to me, but I suppose there’s some room for doubt. (Similarly, the emotion of jealously might be a side-effect of some other computational system, rather than a mechanism to deter infidelity. Could be.)

Is the claim that these structures are for synchronizing leg movements a “Just So” story? Does a structure’s shape, in itself, allow you to increase your confidence in a specific functional hypothesis? If you’re working in the realm of behavior, what is the equivalent of measuring and documenting the shapes of structures?

How do (these) biologists support their functional claims?

17. September 2013 by kurzbanepblog
Categories: Blog | 21 comments

Is Taking Performance Enhancing Drugs Like Eating Your Cat?

Every Sunday, the New York Times Magazine runs a column called The Ethicist in which Chuck Klosterman prints a reader question – some sort of moral quandary – and issues a ruling, usually about whether some action (or inaction) is moral or ethical. I thought I’d make a few remarks about Klosterman’s answer to this week’s question, which I reproduce here in its entirety:

The argument against performance-enhancing drugs in sports is that the drugs give players an unfair advantage. But how do P.E.D.’s differ from Tommy John surgery? Or pre-emptive Tommy John surgery? What about rich kids? Is their access to superior coaching, facilities and equipment a similarly unfair advantage? In a society that embraces plastic surgery, Botox injections, Viagra and all kinds of enhancements, what moral line do P.E.D.’s cross? LYNN MOFFAT, SLEEPY HOLLOW, N.Y.

Summarizing, Klosterman answered that P.E.D.s basically don’t cross any obvious line and that they don’t differ from these other ways that you can improve performance, and, therefore, that there’s no moral justification for banning them, writing: “Virtually all moral arguments against P.E.D.’s involve contradictions.”

Why, then, are P.E.D.s banned? Klosterman explains that it has to do with the fact that sports and life differ because sports are a realm of fantasy:

Sports, unlike life, need inflexibly defined rules. Any game (whether it’s the World Cup or Clue) is a type of unreality in which we create and accept whatever the rules happen to be… So how do we make an unreal exhibition meaningful? By standardizing and enforcing its laws, including the ones that don’t necessarily make sense.

He concludes with:

The motive is to create a world — or at least the illusion of a world — where everyone is playing the same game in the same way. P.E.D.’s are forbidden because that’s what our fabricated rules currently dictate. In real life, that’s a terrible, tautological argument. But in sports, arbitrary rules are necessary. The rules are absolutely everything, so the rules are enough.

I have two bones to pick with this answer.

Here’s bone number one. It seems to me he hasn’t quite paid out why games need rules. The issue isn’t just creating a fantasy world. It’s more than that because games – sports –have functions. Many sports let you practice skills which might come in handy in real conflicts, for instance. And one function of sports is not unlike the displays of non-humans in the real world: to see who’s better. Bull elk fight with their antlers in a game that is anything but fantasy. Still, these fights have “rules” – no using your antlers against the opponent’s flanks – and allow both participants and observers to make inferences about who is top elk while limiting damage. The rule lets the contest be decided in a truth-revealing way that also (usually) minimizes damage to the participants.

Is he using P.E.D.s?

Is he using P.E.D.s?

Related, a key element of “rules” that is missing here is that many rules in games make the task harder. Consider “rules” that you make when you play by yourself. Let’s see how many times I can throw this ball up without catching it… but the ball has to go at least a few feet in the air. Without such rules, tasks are too easy, limiting their ability to hone skills, and thus their utility.

But the bone I’m more interested in bone number two. Are rules in games and sports so different from moral rules in life? Why is ok to have sex with someone who buys you dinner, but not ok if you explicitly pay someone the cost of dinner for sex? Why is it not ok to have sex with someone for money… but you can make it ok if you make a video of it? Why can you sell your hair and eggs (if you have any), but not your kidney? Why is killing 100,000 people with regular weapons less deserving of punishment than killing 1,400 of them with non-conventional ones?

There are contradictions aplenty embodied in the law as well in people’s personal moral stances, and the literature in moral psychology has a lot of fun with such things. The last decade or so has seen an ebullience of work on the famous Trolley Problem, in which people say it’s not OK to pitch the guy with the backpack off the footbridge to save five others, but it’s fine to kill one to save five if the means of doing so involves pulling a switch instead of pushing someone. The person is just as dead either way, yet our moral intuitions differ drastically. (Another trolley problem paper just came out, by the way.)

Is it true that “sports, unlike life, need inflexibly defined rules?” Life seems to have some inflexibly defined rules as well, as embodied in Immanuel Kant’s notion of a categorical imperative. The convolutions of moral rules both in law and our intuitions don’t seem all that different from the rules of games and sports.

Why might that be? Klosterman gets it right, I think, when he points out that the point of rules is to make sure that “everyone is playing the same game in the same way.” A key aspect of rules and morality is impartiality, that the rules apply to everyone equally. People who break the rules are taking advantage, whether in sports or in life.

The arbitrariness of moral rules, and the contradictions among moral rules, is important to notice in the context of the function of moral psychology. As I and others have argued elsewhere, if moral psychology were, as some would have it, designed around making people better off, then the patterns of moral judgments we see in which people are happy to endorse welfare-destroying rules – such as the prohibition against eating certain foods or against pushing one to save five – are deeply puzzling anomalies. If, on the other hand, moral intuitions serve a different function, then this similarity between moral rules and rules in games is less of a puzzle.

In this sense, then, the prohibition against performance-enhancing drugs is really not so different from the sorts of rules that we outside of sports contexts, rules that can’t be easily justified but exist nonetheless, such as the prohibition against eating one’s own pets.

In this sense, I’m no more satisfied with the more or less vacuous idea that “P.E.D.’s are forbidden because that’s what our fabricated rules currently dictate” than I am with similar justifications for moral rules in the real world that are little more than references to history, tradition, or, often, a general feeling of malaise. In the P.E.D. case, it could be that allowing the drugs would make the sport more interesting – more home runs and all that – but at the expense of the health of the players, to the extent that the drugs have harmful side-effects. Owners, players and spectators might well have different positions on this; lots of rules are already in place that some people think make the game less interesting to the benefit of the participants. (Safety equipment generally falls into this category.) By the same token, the debate about puzzling moral rules in real life could – and I would say, should – have the same character: what trade-offs are we making under each candidate rule regime?

05. September 2013 by kurzbanepblog
Categories: Blog | 7 comments

Burying Beetle Begging Behavior

I generally avoid posting on research in the non-human literature because I’ve received feedback that – more or less – readers are more interested in People Stuff than Animal (or plant) Stuff. (The frequency of comments on posts provides converging evidence.) Not only that, but the paper I’m writing about today hit the mainstream press, and I usually avoid such papers because I prefer to try to find the cooler parts of the pillow. But I’m breaking with tradition here because 1) the paper is about burying beetles, with whom I feel a special affinity, 2) the research is neat, and 3) I’m giving myself latitude to do as I please right now because I’m still sporting this Verra-be-damned sling on my arm.

The research I discuss below focuses on the burying beetle (Nicrophorus vespilloides), which has a really interesting life history. The females of this species lay eggs inside or near the body of a dead animal, such as a mouse. A few days later, the eggs hatch, and the larvae feed on the carcass. That’s already nifty, but wait, there’s more. After the larvae hatch, mom eats some of them, and regurgitates their bodies to feed the cannibalized larvae’s siblings.

My interest in these critters derives from this cannibalistic behavior, which I will discuss even though it’s really tangential to the point. The reason mom eats her babies can be reasonably easily explained with the usual theoretical tools. If mom allowed all the larvae to survive, she could be left with a large number of small ones instead of a slightly smaller number of larger ones, with better chances out in the world. And, of course, no sense letting good calories go to waste. So, killing some to feed others is fitness-enhancing, and explains the behavior. I and my coauthors used this species as an example in a paper about moral dilemmas. Generally, when organisms are faced with a decision to kill one offspring (or sibling) to save five offspring (or siblings), inclusive fitness theory suggests that they should choose to do so. And that seems to be just how burying beetle brains work, reflecting this calculus, killing some to save more. What’s interesting (to some of us) is that humans, at least in self-report data, radically violate the predictions of the theory, with most people saying they would not push one brother off the famous footbridge to save five brothers, and even more say that it is morally wrong to do so. This illustrates that morality, whatever it is, is a sufficiently strong psychological force that it contravenes kin selected systems under these (granted, hypothetical) circumstances.

All of which is, again, more or less beside the point. Andrews and Smiseth, in their recent paper in Behavioral Ecology, were interested in larvae begging behavior. Larvae beg for food by raising their little heads to their parents and waving their legs indicating their desire to be fed. In the first study, the authors were interested in looking at who is really in control of the transfer of food from mom to larvae. It could be the larvae themselves – big larvae jostle little larvae away from mom – or it could be mom, choosing to regurgitate into the mouths of larger larvae at the expense of the little ones. This difference looms large in the context of why larvae beg: Is begging a way to compete with other larvae – scramble competition – or is begging a signal to parents that they can then use to decide who will be fed?

To get at this, the authors took “junior” (24 hours old) and “senior” (48 hours old) larvae and put them with either a live or dead mother beetle. (The authors note that this independent variable is imperfect: “We obviously acknowledge that dead parents will differ in other respects from live parents, especially with respect to whether they interact with their larvae.”) They then measured how much senior and junior larvae begged for food and how “successful” they were. Here, “success” means making mouth-to-mouth contact with mom. The results of this experiment were that senior larvae did much better than junior larvae when mom was alive, but there was no difference when she was dead. This implies that it’s mom’s behavior, rather than inter-larvae wrestling, than leads to begging success. Mom, not the larvae, seem to be controlling who gets fed. Begging, then, seems to act as some sort of signal.

So, if begging is a signal, what sort of signal is it? Is begging costly? As readers of this blog are likely to already know, the issue of cost looms very large in the context of signals, making this a key question. To measure if begging is costly, they looked at the larvae that mom ate. Did they tend to be the ones who were begging, or not? Indeed, begging seems to draw mom’s fatal ire. As the authors put it: “Thus, the risk that a begging larva fell victim to cannibalism was more than 13 times greater than expected if parents targeted larvae irrespective of their behavior.” Begging for food is hazardous to one’s health. The authors conclude as follows:

These findings suggest that offspring begging increases the parents’ influence over food allocation and that begging is costly by increasing the offspring’s risk of being a target of filial cannibalism. Our results support the assumptions of honest signaling models for the resolution of parent–offspring conflict.

Finally, I want to note that Andrews and Smiseth spend a few lines of their Discussion linking the beetle data to both birds and humans, writing that “evidence from humans argues against a parent-induced cost of begging (crying), whereas evidence from studies on birds is inconclusive…”


Andrews, C. P., & Smiseth, P. T. (2013). Differentiating among alternative models for the resolution of parent–offspring conflict. Behavioral Ecology.


27. August 2013 by kurzbanepblog
Categories: Blog | 2 comments

Theories in Psychology – A Gigerenzian View

As I alluded in a prior post, I’m spending August convalescing, which is my excuse for why this post draws largely on quoting someone else’s work. With my right arm in a sling, typing is like putting sunscreen on your own back; it can be done, but it requires uncomfortable contortions.

So, with that, I’m writing today – or, really, mostly cutting and pasting – from a paper that I really like but am guessing most readers haven’t read, “Surrogates for Theories” by Gerd Gigerenzer, published fifteen years ago, in 1998. I kind of love this little paper, and commend it to everyone, especially students. I begin where he ended. Gigerenzer writes:

Several years ago, I spent a day and a night in a library reading through issues of the Journal of Experimental Psychology from the 1920s and 1930s. This was professionally a most depressing experience. Not because these articles were methodologically mediocre. On the contrary, many of them make today’s research pale in comparison to their diversity of methods and statistics, their detailed reporting of single-case data rather than mere averages, and their careful selection of trained subjects. And many topics—such as the influence of the gender of the experimenter on the performance of the participants—were of interest then as now. What depressed me was that almost all of this work is forgotten; it does not seem to have left a trace in the collective memory of our profession. It struck me that most of it involved collecting data without substantive theory. Data without theory are like a baby without a parent: their life expectancy is low.

The short paper takes a broad view of the field of psychology, focusing on what counts as theory in the field, with an emphasis on four strategies that Gigerenzer thinks stand as “surrogates” for real theories; surrogates, he says “are vague, imprecise, and/or practically unfalsifiable, that they often boil down to common sense.” I’ll discuss just two. In essence, Gigerenzer is reacting to the fact that, in psychology, “almost anything passes as a theory.” I leave it to the reader to judge if things have changed in the ensuing fifteen years.

The first surrogate Gigerenzer discusses are “one word explanations.” Of these, he says:

Such a word is a noun, broad in its meaning and chosen to relate to the phenomenon. At the same time, it specifies no underlying mechanism or theoretical structure. The one-word explanation is a label with the virtue of a Rorschach inkblot: a researcher can read into it whatever he or she wishes to see.

Working in the literature in judgment and decision making, Gigernezer has in mind terms like “availability” and “similarity,” words used in the heuristics and biases tradition. A central difficulty is that because they are single words instead of well-specified models, nearly any result can be viewed as consistent with one (or more) of these “explanations.” In this sense, they are not scientific explanations at all. My view is that it remains good practice to be vigilant about putative explanations that are single words, such as “culture,” “learning,” or “plasticity.”

A second issue that Gigerenzer raises is “muddy dichotomies.” He begins by emphasizing that “There is nothing wrong with making distinctions in terms of dichotomies per se,” but rather the issue is “situations in which theoretical thinking gets stuck in binary oppositions beyond which it never seems to move.” Again begging the reader’s indulgence, here is a lengthy quotation from the paper:

Let us consider a case in which false dichotomies have hindered precise theorizing. Some arguments against evolutionary psychology are based on the presumed dichotomy between biology and culture, or genes and environment (Tooby & Cosmides, 1992). One such argument goes: Since cognition is bound to culture, evolution must be irrelevant. But biology and culture are not opposites. For instance, our ability to cooperate with conspecifics to whom we are genetically unrelated— which distinguishes us humans from most other species—is based on mechanisms of both biological and cultural origin. Simply to ask about the relative importance of each in terms of explained variance, such as that 80 percent of intelligence is genetically inherited, is, however, not always an interesting question. The real theoretical question concerns the mechanism that combines what is termed the “biological” and the “cultural.” For biologists, the nature/nurture or biological/cultural dichotomy is a non-starter: genes are influenced by their environment, which can include other genes.

Part of Gigerenzer’s agenda is explaining why surrogates for theories are a particular problem in psychology. He discusses null hypothesis testing as one source of the problem; my perception is that psychology is moving – not as fast as many would like – away from the sorts of practices Gigerenzer is pointing to. I’m not as sure about the second culprit Gigerenzer identifies, the isolation of sub-disciplines within psychology.

Each subdiscipline has its own journals, reviewers, and grant programs, and one can have a career in one of them without ever reading the journals of neighboring subdisciplines. In addition, job searches are often organized according to these categories. This territorial organization of psychology discourages researchers from engaging with psychological knowledge and colleagues outside of their territory… [and] blocks the flow of metaphors and the development of new theories. Distrust and disinterest in anything outside one’s subdiscipline supports surrogates for theory.

Gigerenzer suggests that surrogates for theory “flourish like weeds.” Of course, that was fifteen years ago. Surely things have improved with the passage of time. Right?


Gigerenzer, G. (1998). Surrogates for theories. Theory and Psychology8, 195-204.

08. August 2013 by kurzbanepblog
Categories: Blog | 7 comments

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