The Fight Over Mankind’s Essence

All traits of biological organisms require some combination and interaction of genetic and non-genetic factors to develop. As Tooby and Cosmides put it in their primer:

Evolutionary psychology is not just another swing of the nature/nurture pendulum. A defining characteristic of the field is the explicit rejection of the usual nature/nurture dichotomies — instinct vs. reasoning, innate vs. learned, biological vs. cultural. What effect the environment will have on an organism depends critically on the details of its evolved cognitive architecture.

The details of that cognitive architecture are, to some extent, what people seem to be referring to when they use the word “innate”, and figuring out the details of that architecture is a monumental task indeed. For some reason, this task of figuring out what’s “innate” also draws some degree of what I feel is unwarranted hostility and precisely why it does is a matter of great interest. One might posit that some of this hostility is due to the term itself. “Innate” seems to be a terribly problematic term for the same two reasons that most other contentious terms are: people can’t seem to agree on a clear definition for the word or a  context to apply it in, but they still use it fairly often despite that. Because of this, interpersonal communication can get rather messy, much like two teams trying to play a sport in which each is playing the game under a different set of rules; a philosophical game of Calvinball. I’m most certainly not going to be able to step into this debate and provide the definition for “innate” that all parties will come to intuitively agree upon and use consistently in the future. Instead, my goal is to review two recent papers that examined the contexts in which people’s views of innateness vary.

“Just add environment!” (Warning: chicken outcome will vary with environment)

Anyone with a passing familiarity in the debates that tend to surround evolutionary psychology will likely have noticed that most of these debates tend to revolve around issues of sex differences. Further, this pattern tends to hold whether it’s a particular study being criticized or the field more generally; research on sex differences just seems to catch a disproportionate amount of the criticism, relative to most other topics, and that criticism can often get leveled at the entire field by association (even if the research is not published in an evolutionary psychology, and even if the research is not conducted by people using an evolutionary framework). While this particular observation of mine is only an anecdote, it seems that I’m not alone in noticing it. The first of the two studies on attitudes towards innateness was conducted by Geher & Gambacorta (2010) on just this topic. They sought to determine the extent to which attitudes about sex differences might be driving opposition to evolutionary psychology and, more specifically, the degree to which those attitudes might be correlated with being an academic, being a parent, or being politically liberal.

Towards examining this issue, Geher & Gambacorta (2010) created questions aimed at assessing people attitudes in five domains: (1) human sex differences in adulthood, (2) human sex differences in childhood, (3) behavioral sex differences in chickens, (4) non-sex related human universals, and (5) behavioral differences between dogs and cats. Specifically, the authors asked about the extent to which these differences were due to nature or nurture. As mentioned in the introduction, this nature/nurture dichotomy is explicitly rejected in the conceptual foundations of evolutionary psychology and is similarly rejected by the authors as being useful. This dimension was merely used in order to capture the more common attitudes about the nature of biological and environmental causation, where the two are often seen as fighting for explanatory power in some zero-sum struggle.

Of the roughly 270 subjects who began the survey, not all of them completed every section. Nevertheless, the initial sample included 111 parents and 160 non-parents, 89 people in academic careers and 182 non-academics, and the entire sample was roughly 40 years old and mildly politically liberal, on average. The study found that political orientation was correlated with judgments of whether sex differences in humans (children and adults) were due to nature or environment, but not the other three domains (cats/dogs, chickens/hens, or human universals): specifically, those with more politically liberal leanings were also more likely to endorse environmental explanations for human sex differences. Across other domains there were some relatively small and somewhat inconsistent effects, so I wouldn’t make much of them just yet (though I will mention that women’s studies and sociology fields seemed consistently more inclined to chalk each domain – excepting the differences between cats and dogs – up to nurture, relative to other fields; I’ll also mention their sample was small). There was, however, a clear effect that was not discussed in the paper:subjects were more likely to chalk non-human animal behavior up to nature, relative to human behavior, and this effect seemed more pronounced with regards to sex differences specifically. With these findings in mind, I would echo the conclusion of the paper that there is appears to be some political, or, more specifically, moral dimension to these judgments of the relative roles of nature and nurture. As animal behavior tends to fall outside of the traditional human moral domain, chalking their behavior up to nature seemed less unpalatable for the subjects.

See? Men and women can both do the same thing on the skin of a lesser beast.

The next paper is a new release from Knobe & Samuels (2013). You might remember Knobe from his other work in asking people slightly different questions and getting vastly different responses, and it’s good to see he’s continuing on with that proud tradition. Knobe & Samuels begins by asking the reader to imagine how they’d react to the following hypothetical proposition:

Suppose that a scientist announced: ‘I have a new theory about the nature of intention. According to this theory, the only way to know whether someone intended to bring about a particular effect is to decide whether this effect truly is morally good or morally bad.’

The authors predict that most people would reject this piece of folk psychology made explicit; value judgments are supposed to be a different matter entirely from tasks like assessing intentionality or innateness, yet these judgments do not appear to be truly be independent from each other in practice. Morally negative outcomes are rated as being more intentional than morally positive ones, even if both are brought about as a byproduct of another goal. Knobe & Samuels (2013) sought to extent this line of research in the realm of attitudes about innateness.

In their first experiment, Knobe & Samuels asked subjects to consider an infant born with a rare genetic condition. This condition ensures that if a baby breastfeeds in the first two weeks of life it will either have extraordinarily good math abilities (condition one) or exceedingly poor math skills (condition two). While the parents could opt to give the infant baby formula that would ensure the baby would just turn out normal with regard to its math abilities, in all cases the parents were said to have opted to breastfeed, and the child developed accordingly. When asked about how “innate” the child’s subsequent math ability was, subjects seemed to feel that baby’s abilities were more innate (4.7 out of 7) when they were good, relative to when those abilities were poor (3.4). In both cases, the trait depended on the interaction of genes and environment and for the same reason, yet when the outcome was negative, this was seen as being less of an innate characteristic. This was followed up by a second experiment where a new group of subjects were presented with a vignette describing a fake finding about human’s genes: if people experienced decent treatment (condition one) or poor treatment (condition two) by parents at least sometimes, then a trait would reliability develop. Since most all people do experience decent or poor treatment by their parents on at least some occasions, just about everyone in the population comes to develop this trait. When asked about how innate this trait was, again, the means through which it developed mattered: traits resulting from decent treatment were rated as more innate (4.6) than traits resulting from poor treatment (2.7).

Skipping two other experiments in the paper, the final study presented these cases either individually, with each participant seeing only one vignette as before, or jointly, with some subjects seeing both versions of the questions (good/poor math abilities, decent/poor treatment) one immediately after the other, with the relevant differences highlighted. When subjects saw the conditions independently, the previous effects were pretty much replicated, if a bit weakened. However, even seeing these cases side-by-side did not completely eliminate the effect of morality on innateness judgments: when the breastfeeding resulted in worse math abilities this was still seen as being less innate (4.3) than the better math abilities (4.6) and, similarly, when poor treatment led to a trait developing it was viewed as less innate (3.8) than when it resulted from better treatment (3.9). Now these differences only reached significance because of the large sample size in the final study as they were very, very small, so I again wouldn’t make much of them, but I do still find it somewhat surprising that there were still small differences to be talked about at all.

Remember: if you’re talking small effects, you’re talking psychology.

While these papers are by no means the last word on the subject, they represent an important first step in understanding the way that scientists and laypeople alike represent claims about human nature. Extrapolating these results a bit, it would seem that strong opinions about research in evolutionary psychology are held, at least to some extent, for reasons that have little to do with the field per se. This isn’t terribly surprising, as it’s been frequently noted that many critics of evolutionary psychology have a difficult time correctly articulating the theoretical commitments of the field. Both studies do seem to suggest that moral concerns play some role in the debate, but precisely why the moral dimension seems to find itself represented in the debate over innateness is certainly an interesting matter that neither paper really gets into. My guess is that it has something to do with the perception that innate behaviors are less morally condemnable than non-innate ones (hinting at an argumentative function), but that really just pushes the question back a step without answering it. I look forward to future research on this topic – and research on explanations, more generally – to help fill in the gaps of our understanding of this rather strange phenomenon.

References: Geher, G., & Gambacorta, D. (2010). Evolution is Not Relevant to Sex Differences in Humans Because I Want it That Way! Evidence for the Politicization of Human Evolutionary Psychology EvoS: The Journal of the Evolutionary Studies Consortium , 2, 32-47

Knobe, J., & Samuels, R. (2013). Thinking like a scientist: Innateness as a case study Cognition, 126 (1), 72-86 DOI: 10.1016/j.cognition.2012.09.003

Is The Exotic Erotic? Probably Not…

Last time I wrote about the likely determinants of homosexuality, I ended up favoring the pathogen hypothesis that was put forth by Cochran, Ewald, and Cochran (2000) as the theory that had the most currently going for it. What is particularly interesting about my conclusion is how much empirical evidence directly confirms the theory: none. Don’t get me wrong; the pathogen hypothesis is certainly consistent with the known findings about homosexuality – such as the widely-varying reported concordance rates and the large fitness costs associated with the orientation – but being consistent with certain findings is not the same as being demonstrated by that evidence. If the currently most plausible theory for explaining homosexuality has, in essence, no direct evidence in its favor, that clearly must not be saying a lot about the alternative prospects. The two theories I covered last time – kin selection and sexually antagonistic selection – can’t even seem to account well for the existing evidence, so a neutral point with regard to the evidence is actually preferable. There was one theory that I neglected to mention last time, however, and this is a theory that purports to be able to explain both how heterosexual and homosexual orientations come to develop, and in both sexes, no less. If such a theory proved to have anything to it, then, it would be a highly valuable perspective indeed, so it deserves careful inspection.

“Nope; still not finding any indication of plausibility yet. Get the bigger microscope”

The theory, known as “Exotic Becomes Erotic” (EBE) was proposed by Daryl Bem (1996). If that name sounds familiar, it’s because this is the same Daryl Bem who also thought he found evidence for “extra-sensory porn-ception” in 2011, so we’re already not off to a good start. Pressing ahead despite that association, EBE puts the causal emphasis of developing a preferential attraction towards one sex or another on an individual’s perceptions of feeling different from other members of one sex: for instance, if a boy happens to not like sports, he will feel different from the majority of the other boys who do seem to like sports; if he does like sports, he’d feel different from the girls who did not. Following this perception of one sex as exotic, EBE posits that individuals will come to experience “non-specific, autonomic arousal” to the exotic group in question and, subsequently, that arousal will be transformed into an erotic preference for members of the initially exotic group. So, if you feel different from the boys or the girls, regardless of whether you’re a boy or a girl, you’ll come to be vaguely aroused by that sex – either by apprehension, anger, fear, curiosity, or really anything works, so long as it’s physiologically arousing – and then your body will, at some point, automatically turn that arousal into lasting sexual preferences.

Like most of the theories regarding homosexuality I discussed previously, this one also have very little actual evidence to support it. What it does have is a correlation between retrospective reports of childhood gender nonconformity and current sexual orientation. In fact, that single, underwhelming correlation is about all that EBE has going for it; everything else in the model is an assumption that’s largely built off that correlation. While a retrospective correlation is slightly better than having no evidence at all, it’s not better by a whole lot (in much the same way that 53% accuracy at guessing where some stimuli will show up between two options isn’t much better than 50%, yet apparently both are publishable). So, now that we’ve covered what the theory has going for it, let’s consider some of the things that EBE does not have going for it. You might want to take a break now to use the bathroom or get a snack, because this is a long list.

Let’s begin with the matter of this “non-specific physiological arousal”: at a bare minimum, EBE would require that the sex an individual perceived to be the least exotic ought to be consistently less physiologically arousing, on average, than the gender that individual did identify with. Without that arousal, there would be nothing to eventually convert into later sexual preference. So what does Bem have to say about the presence or absence of this arousal?

“To my knowledge, there is no direct evidence for the first step in this sequence beyond the well-documented observation that novel (“exotic”) stimuli produce heightened physiological arousal in many species, including our own”

So, in other words, there is no empirical evidence for this suggestion whatsoever. The problems, however, do not stop there: EBE is also massively under-specified in regards to how this hypothetical “non-specific arousal” is turned into eroticism in some cases but not others. While Bem (1996) proposes three possible mechanisms through which that transition might take place – sexual imprinting, the opponent process, and the extrinsic arousal effect – there are clearly non-human stimuli that produce a great deal of arousal (such as spiders, luxury cars, or, if we are talking about children, new toys) that does not get translated into later sexual attraction. Further, there are also many contexts in which gender-conforming children of the same sex will be around other while highly physiologically aroused (such as when boys are playing sports and competing against a rival team), but EBE would seem to posit that these high-aroused children would not develop any short- or long-term eroticism towards each other.

Nope; nothing even potentially erotic about that…

Bem might object that this kind of physiological arousal is somehow different, or missing a key variable. Perhaps, he might say, that in addition to this yet-to-be-demonstrated arousal, one also needs to feel different from the target of that arousal. Without being both exotic and arousing, there will be no lasting sexual preference developed. While such a clarification might seem to rescue EBE conceptually in this regard, the theory again falters by being massively under-specified. As Bem (1996) writes:

“…[T]he assertion that exotic becomes erotic should be amended to exotic – but not too exotic – becomes erotic. Thus, an erotic or romantic preference for partners of a different sex, race, or ethnicity is relatively common, but a preference for lying with the beasts in the field is not.”

In addition to not figuring out whether the arousal required for the model to work is even present, in no treatment of the subject does Bem specify precisely how much arousal and/or exoticism ought to be required for eroticism to develop, or how these two variables might interact in ways that are either beneficial or detrimental to that process. While animals might be both “exotic” and “highly arousing” to children, very rarely does a persistent sexual preference towards them develop; the same can be said for feelings between rival groups of boys, though in this case the arousal is generated by fear or anger. EBE does not deal with this issue so much as it avoids it through definitional obscurity.

Continuing along this thread of under-specificity, the only definition of “exotic” that Bem offers involves a perception of being different. Unfortunately for EBE, there are a near incalculable number of potential ways that children might feel different from each other, and almost none of those potential representations are predicted to result in later eroticism. While Bem (1996) does note that feeling different about certain things – interest in sports seems to be important here – appears to be important for predicting later homosexual orientation, he does not attempt to explain why feeling different about gender-related variables ought to be the determining factor, relative to non-gender related variables (such as intelligence, social status, or hair color). While erotic feelings do typically develop along gendered lines, EBE gives no a priori reason for why this should be expected. One could imagine a hypothetical population of people who develop preferential sexual attractions to other individuals across any number of non-gendered grounds, and EBE would have little to say about why this outcome does not obtain in any known human population.

The problem with this loose definition of exotic does not even end there. According to the data presented by Bem, many men and women who later reported a homosexual attraction also reported having enjoyed gender-typical activities (37 and 37%, respectively), having been averse to gender-atypical activities (52 and 19%), and having most of their childhood friends be of their same sex (58 and 40%). While these percentages are clearly different between homosexual and heterosexual respondents – with homosexuals reporting enjoying typical activities less, atypical ones more, and being more likely to predominately have friends of the opposite sex – EBE would seem to be at loss when attempting to explain why roughly half of homosexual men and women do not seem to report differing from their heterosexual counterparts in these important regards. If many homosexuals apparently did not view their own sex to be particularly exotic during childhood, there could be no hypothetical arousal and, accordingly, no eroticism. This is, of course, provided these retrospective accounts are even accurate in the first place and do not retroactively inflate the perceptions of feeling different to accord with their current sexual orientation.

“In light of not being hired, I can now officially say I never wanted your stupid job”

On a conceptual level, however, EBE runs into an even more serious concern. Though Bem (1996) is less than explicit about this, it would seem his model suggests that homosexuality is a byproduct of an otherwise adaptive system designed for developing heterosexual mate preferences. While Bem (1996) is likely correct in suggesting that homosexuality is not adaptive itself, his postulated mechanism for developing mate preference would likely have been far too detrimental to have been selected for. Bem’s model would imply that the mechanism responsible for generating sexual attraction, when functioning properly, functions so poorly that it would, essentially, render a rather large minority of the population effectively sterile. This would generate an intense selection pressure either towards any modification of the mechanism that did not preclude its transfer from one generation to the next or decisive selection towards a much greater gender conformity. Neither outcome seems to have obtained, which poses a new set of questions regarding why.

Precisely how such a poorly-functioning mechanism would have even come to exist in human populations in the first place is a matter that Bem never addresses. A major issue with the EBE perspective, then, is that it more-or-less takes for granted the base rate existence of homosexuality in human populations without asking why it ought to be that prevalent for humans but almost no other known species. Though Bem does not discuss it, almost every other species appears to navigate the process of developing sexual attraction in ways that do not result in large numbers of males or females developing exclusive same-sex attractions. If this was any other key adaptation, such a vision, and significant minorities of the population consistently went blind at very young ages in a world where being able to see is adaptive, we would want a better explanation for that failure than the kind that EBE can provide. Now if only the creator of EBE has some kind of ability to see into the future – an extra-sensory ability, if you will – to help him predict that his theory would run into these problems, they might have been avoided or dealt with…

References:Bem, D. (1996). Exotic becomes erotic: A developmental theory of sexual orientation. Psychological Review, 103 (2), 320-335 DOI: 10.1037//0033-295X.103.2.320

Cochran, G., Ewald, P., & Cochran, K. (2000). Infectious Causation of Disease: An Evolutionary Perspective Perspectives in Biology and Medicine, 43 (3), 406-448 DOI: 10.1353/pbm.2000.0016

Full Frontal Nerdity: Understanding Elitists And Fakes

“There is no such thing as “fake geek girls”; there are, only, girls who are at different, varying levels of falling in love with something that society generically considers to fall under the “nerd culture” category” -albinwonderland

About a month ago, Tony Harris (a comic book artist) posted a less-than-eloquently phrased rant about how he perceived certain populations within the geek subculture to be “fakes”; specifically, he targeted many female cosplayers (for a more put-together and related train of thought, see here). Predictably, reactions were had and aspersions were cast. Though I have barely dipped my toes into this particular controversy, the foundations of it are hardly new. This experience – the tensions between the “elites” and “fakes” – is immediately relatable to all people, no matter how big of a fish they happen to be in the various social ponds they inhabit. While the specific informal rules of subcultures (how one should dress, what one may or may not be allowed to like, and so on) may differ from group to group, these superficial differences dissolve into the background when considering the underlying similarities of their logic; nerd culture will just be our guide to it at present.


I get the sense that, because the issue involved gender, a good deal of the collective cognitive work that went into this debate focused on generating and defending against claims of sexism, which, while an interesting topic in its own right, I find largely unproductive for my current purposes. In the interests of examining the underlying issues without the baggage that gender brings, I’d like to start by answering a seemingly unrelated question: why might Maddox feel that bacon has been “ruined” for him by its surge in popularity?

The Internet needs to collectively stop sucking Neil deGrasse Tyson’s dick. And add bacon and zombies to that list. I love bacon, but fuck you for ruining it, everyone. Holy shit, just shut the fuck up about bacon. Yeah, it’s great, we know. Bacon cups, bacon salt, bacon shirts, bacon gum, bacon, bacon, bacon, WE GET IT. Bacon is your Jesus, we know, now do a shot of bleach and take some buckshot to the face.

This comment likely seems strange (if also a bit relatable) to many people: why should anyone else’s preferences influence Maddox’s? If I like chocolate ice cream, it would indeed be odd if I started liking it less if I was around other people who also seemed to like it, especially if the objective properties of the ice cream in question haven’t changed; it’s still the same ice cream (or bacon) that was there a moment ago. It seems clear from that consideration that bacon per se isn’t what Maddox feels has been ruined. What Maddox doesn’t seem to like is that other people like it; too many other people, however many that works out to be. So now that we’ve honed the question somewhat (why doesn’t Maddox like that other people like bacon?), let’s turn to Dr. Seuss to, at least partially, answer it.

In Dr. Seuss’s story, The Sneetches, we find an imaginary population of anthropomorphic birds, some of which have a star on their belly and others of which do not. The Sneetches form group memberships along these lines, with the stars – or lack thereof – serving as signals for which group any given Sneetch belongs to. Knowing whether or not a Sneetch had a star could, in this world, provide you with useful information about that individual: where might this Sneetch stand socially, relative to its peers; who might this Sneetch tend to associate with; what kind of resources might this Sneetch have access to. However, when a man rolls into town and starts to affix stars to the bellies of the starless Sneetches, this system gets thrown out of order. The special status of the initially-starred Sneetches is now questioned, because every Sneetch is sending an identical signal, meaning that signal can no longer provide any useful information. The initially-starred Sneetches then, apparently feeling that the others have “ruined” stars for them, subsequently remove their stars in an attempt to restore the signal value and everyone eventually learns something about racism. In this example, though, it becomes readily apparently why preferences for having stars changed: it was the signal value of the stars – the information they conveyed – that changed, not the stars themselves, and this information is, or rather, was, a valuable resource.

The key insight here is that if an individual is trying to signal some unique quality about itself, it does them no good to try and achieve that goal through a non-unique or easy-to-fake signal. Any benefits that the signal can bring will soon be driven to non-existence if other organisms are free to start sending that same signal. So let’s apply that lesson back to bacon question: Maddox is likely bothered by too many other people liking bacon because, to some extent, it means the signal strength of his liking bacon has been degraded. As part of Maddox’s affinity for bacon seemed to extend beyond its physical properties, some part of his affinity for the product was lost with that signal value; it no longer said much about him as a person. You’ll notice that I’ve forgone the question of what precisely Maddox might have been trying to signal by advertising his love of bacon. I’ve done this because, while it might be an interesting matter in its own right, it’s entirely beside the point. Regardless of what the signal is supposed to be about, ubiquitousness will always threaten it.

The “Where’s Waldo” principle

While many might be tempted to take this point as a strike against the elitists (“they don’t really like what they say they like; they only like what liking those things says about them”, would resemble how that might get phrased), it’s important to bear in mind that this phenomenon is not restricted to the elites. As Maddox suggests in his post, many of the people whom he deems to be “fake” nerds are attempting to make use of that signal value themselves, despite lacking the trait that the signal is supposed to advertise:

 People love science in the same way they love classical music or art. Science and “geeky” subjects are perceived as being hip, cool and intellectual. So people take a passing interest just long enough to glom unto these labels and call themselves “geeks” or “nerds” every chance they get.

Like the starless Sneetches, these counterfeiters are trying to gain some benefit (in this case, perhaps the perception that they’re intelligent or interesting) through a dishonest means (by not being either of those things, but still telling people they are). This poses a very real social problem for signalers to overcome: how to ensure that (their) communication is (perceived as being) honest so the value of the communication can be maintained (for them)? If I can send a signal that advertises some latent quality about myself, I can potentially gain some benefit by doing so. However, if people who do not have that underlying quality also start sending the signal, they can reap those same benefits at my expense. The resources in question here are zero-sum, so more of those resources going to others means less for me, and vice versa. This means it’s in my interests to send signals that others cannot send in order to better monopolize those benefits, and to likewise strive to give receivers the impression that my signal is of a greater value than the signals of others.

Despite being beset by possible deception from senders, it is also in the interests of those receiving the signals that said signals remain honest. Resources, social or otherwise, that I invest in one individual cannot also be invested in another. Accordingly, when deciding how to allocate that limited investment budget, it’s in my interests to do so on the basis of good information; information which I would no longer have access to as the signal value degrades. Appreciating this problem helps answer a question posed by BlackNerdComedy: why does he remember information about an obscure cartoon called “SpaceCats”? More generally, he wonders aloud why people get “challenged” on their gamer credibility on the basis of their obscure knowledge and what purpose such challenges might serve (ironically, he also has another video where he complains about how some nerds consider others to not be “real nerds”, and then goes on to say that the people judging others for not being “real nerds” are, themselves, not “real nerds” because of it). In the light of the communication problem, the function of these challenges seems to become clear: they’re attempts at assessing honesty. Good information about someone’s latent qualities simply cannot be well-assessed by superficial knowledge. In much the same way, the depths of one’s math abilities can’t be well-assessed by testing on basic addition and subtraction alone; testing on the basics simply doesn’t provide much useful information, especially if the basics are widely known. If you start giving people calculus problems to do instead, you now have a better gauge for relative math abilities.

Obscure knowledge is no the only means through which one can try and guarantee the honesty of the signal, however. Another point that has frequently been raised in this debate involves people talk about “paying your dues” in the community, or suffering because of one’s nerdy inclinations. As Maddox puts it:

Well someone forgot to give the “nerds-are-sexy” memo to my friends, because most of them are nerds and none of them are getting laid. Here’s a quick rule of thumb: if you don’t have to make an effort to get laid, you’re not a nerd.Being a nerd is a byproduct of losing yourself in what you do, often at the expense of friends, family and hygiene. Until or unless you’ve paid your dues, you aren’t welcome.

For starters, the emphasis on costs is enlightening: paying costs helps ensure the signal is harder to fake (Zahavi, 1975), and the greater those costs, the more likely the signal is honest. If someone is socially ridiculed for their hobby, it’s a fairly good sign that they aren’t doing it just to be popular, as this would be rather counterproductive. Maddox’s comment also taps into the distinction that Tooby and Cosmides (1996) made in regards to “genuine” and “fair-weather” friends: genuine friends have a deep interest in your well-being, making them far less likely to abandon you when the goings get tough. By contrast, fair-weather friends stick around only so long as your deliver them the proper benefits, but will be more likely to turn on you or disappear when you become too costly. Again, people are faced with the problem of discriminating one type from the other in the face of less-than-honest communication. Just because someone tells you they deeply value your friendship, it doesn’t mean that they have your best interests at heart. This requires people to make use of other cues in assessing the social commitments of others and, it seems, one good way of doing this involves looking for people who literally have no other social prospects. If one has been rejected by all other social groups except the nerd community, they will be less likely to abandon that community because they have no better alternative. By contrast, those who are deemed to have plenty of viable social alternatives (such as physically attractive people) can be met with a greater degree of skepticism; they have other avenues they could take if the going gets too rough, which might suggest their social commitment is not as strong as it could otherwise be.

His loyalty to the nerd community is the only strong thing about him.

This is only a general sketch of the some of the issues at play in this debate; the specifics can get substantially more complicated. For instance, the goal of a signaler, as mentioned before, is to beat out other signalers, and this can involve a good deal of dishonesty in the signaler’s representations of other signalers. It’s worth bearing in mind that all signalers, whether they’re “real” or “fake”, have this same vested interest: beating the other signalers. Being honest is only one way of potentially doing that. There’s also the matter of social value, in that even if a signaler is sending a completely honest signal about their latent qualities and commitments, they might, for other reasons, simply not be very good social investments to most people, even within the community. As I said, it gets complicated, and because the majority of these calculations seem to be made without any conscious awareness, the subject gets even trickier to untangle.

One final point of the debate that caught my eye was the solution that people from either side of the debate appear to agree on (at least to some extent) for dealing with the problem: people should stop trying to label themselves as “gamers” or “nerds” altogether and simply enjoy their hobbies. In the language of the underlying theory, people can free themselves from harassment (from within the community, anyway) if they stop trying to signal something about themselves to others, and, by proxy, stop competing for whatever resources at are stake, through their hobbies. The problem with this suggestion is two-fold: (a) the resources at stake here are valuable, so it’s unlikely that competition for them will stop, and (b) most people don’t consciously recognize they’re competing in the first place; in fact, most people would explicitly deny such an implication. After all, if one is trying to maintain the perception they’re honestly saying something about themselves, it would do them no favors to acknowledge any ulterior motives, as this acknowledgement would tend to degrade the value of their signals on its own. It would degrade them, that is, unless one is trying to signal they’re more conscious of their own biases than other people, and a good social partner because of it…

References: Tooby, J., & Cosmides, L. (1996). Friendship and the banker’s paradox: Other pathways to the evolution of adaptations for altruism. Proceedings of The British Academy, 88, 119-143

Zahavi, A. (1975). Mate selection—A selection for a handicap Journal of Theoretical Biology, 53 (1), 205-214 DOI: 10.1016/0022-5193(75)90111-3

The Drifting Nose And Other “Just-So”s

In my last post dealing with PZ Myer’s praise for the adaptationist paradigm, which was confusingly dressed up as criticism, PZ suggested the following hypothesis about variation in nose shape:

Most of the obvious phenotypic variation we see in people, for instance, is not a product of selection: your nose does not have the shape it does, which differs from my nose, which differs from Barack Obama’s nose, which differs from George Takei’s nose, because we independently descend from populations which had intensely differing patterns of natural and sexual selection for nose shape; no, what we’re seeing are chance variations amplified in frequency by drift in different populations.

Today’s post will be a follow-up on this point. Now, as I said before, I currently have no strong hypotheses about what past selection pressures (or lack thereof) might have been at work shaping the phenotypic variation found in noses; noses which differ in shape and size noticeably from chimps, gorillas. orangutans, and bonobos. The cross-species consideration, of course, is a separate matter from phenotypic variation within our species, but these comparisons might at least make one wonder why the human nose might look the way it does compared to other apes. If that reason(s) could be discerned, it might also tell us something about current types of variation we see in modern human populations. The reason why noses vary between species might indeed be “genetic drift” or “developmental constraint” rather than “selection”, just as the answer to within-species variation of that trait might be as well. Before simply accepting those conclusions as “obviously true” on the basis of intuition alone, though, it might do us some good to give them a deeper consideration.

Follow your nose; it always knows! Alternatively, following evidence can work too!”

One of the concerns I raised about PZ’s hypothesis is that it does not immediately appear to make anything resembling a novel or useful prediction. This concern itself is far from new, with a similar (and more eloquently stated) point being raised by Tooby and Cosmides in 1997 [H/T to one of the commenters for providing the link]:

Modern selectionist theories are used to generate rich and specific prior predictions about new design features and mechanisms that no one would have thought to look in the absence of these theories, which is why they appeal so strongly to the empirically minded….It is exactly this issue of predictive utility, and not “dogma”, that leads adaptationists to use selectionist theories more often than they do Gould’s favorites, such as drift and historical contingency. We are embarrassed to be forced, Gould-style, to state such a palpably obvious thing, but random walks and historical contingency do not, for the most part, make tight or useful prior predictions about the unknown design features of any single species.

That’s not to say that one could not, in principle, derive a useful or novel prediction from the drift hypothesis; just that one doesn’t immediate jump out at me in this case, nor does PZ explicitly mention any specific predictions he had in mind. Without any specific predictions, PZ’s suggestion about variation in nose shape, while it may well be true to some small or large degree (given that PZ’s language chalks most to all of variation up to drift, rather than selection; it’s unclear precisely what proportion he had in mind), his claim also runs the risk of falling prey to the label of “just-so story“.

Since PZ appears to be really concerned that evolutionary psychologists do not make use of drift in their research as often as he’d like, this, it seems, would have been the perfect opportunity for him to show us how things ought to be done: he could have derived a number of useful and novel predictions from the drift hypothesis and/or shown how drift might better account for some aspects of the data in nose variation that he had in mind, relative to other current competing adaptationist theories on nose variation. I’m not even that particular about the topic of noses, really; PZ might prefer to examine a psychological phenomenon instead, as this is evolutionary psychology he’s aiming his criticisms at. This isn’t just a mindless swipe at PZ’s apparent lack of a testable hypothesis either: as long as his predictions derived from a drift hypothesis lead to some interesting research, that would be a welcome addition to any field.

Let’s move on from the prediction point towards the matter of whether selection played a role in determining current nose variation. In this area, there is another concern of mine about the drift hypothesis that reaches beyond the pragmatic one. As PZ mentions in his post, selection pressures are generally “blind” to very small fitness benefits or detriments. If your nose differs in size from mine by 1/10 of a millimeter, that probably won’t have much of an effect on eventual fitness outcomes, so that variation might stick around in the next generation relatively unperturbed. The next generation will, in turn, introduce new variation into the population due to sexual recombination and mutation. If the average difference in nose shape was 1/10 of a millimeter in the previous generation, that difference may now grow to, say, 2/10th of a millimeter. Since that difference still isn’t likely enough to make much of a difference, it sticks around into the next generation, which introduces new variation that isn’t selected for or against, and so on. These growths in average variation, while insignificant when considered in isolation, can begin to become the target of selection as they accumulate and their fitness costs and benefits begin to become non-negligible. In this hypothetical example, nose shape and size might begin to become the target of stabilizing selection where the more extreme variations are weeded out of the population, perhaps because they’re viewed as less sexually appealing or become less functional than other, less extreme variants (the factors that PZ singled out as not being important).

Ladies; start your engines…

So let’s say one was to apply an adaptationist research paradigm to nose variation and compare it to PZ’s drift hypothesis (falsely assuming, for the moment, that an adaptationist research paradigm is in some way supposed to be opposed to a drift one). A researcher might begin by wondering what functions nose shape could have. Note that these need not be definitive conclusions; merely plausible alternatives. Once our researcher has generated some possible functions, they would begin to figure out ways of testing these candidate alternatives. Noback et al (2011), for instance, postulated that the nasal cavity might function, in part, to warm and humidify incoming air before it reaches the lungs and, accordingly, predicted that nasal cavities ought to be expected to vary contingent on the requirements of warming and humidifying across varying climates.

This adaptationist research paradigm generated six novel predictions, which is a good start compared to PZ’s zero. Noback et al (2011) then tested test predictions against 100 skulls from 10 different populations spanning 5 different climates. The resulted indicated significant correlations between nearly every climate factor (temperature and humidity) and nasal cavity shape. Further, the authors managed to disconfirm more than one of their initial hypotheses, and were also able to suggest that these variations in nasal cavity shape were not due solely to allometric effects. They also mention plenty of variation is left unexplained, and some variation in nasal cavity variation might also be due to tradeoffs between warming and humidifying incoming air and functions of the nose (such as olfaction).

So, just to recap, this adaptationist research concerning nose variation yielded a number of testable predictions (it’s useful), found evidence consistent with them in some cases but not others (it’s falsifiable), tested alternative explanations (variation not solely due to allometry), mentioned tradeoffs between functions, and left plenty of variation unexplained (did not assume every feature was an adaptation). This is compared to PZ’s drift hypothesis, which made no explicit predictions, cited no data, made no mention of function (presumably because it would postulate there isn’t one), and would seem to not be able to account well for this pattern of results. Perhaps PZ might note this research deals primarily with internal features of the nose; not external ones, and the external features are what he had mind when he proposed the drift hypothesis. As he’s not explicit about which parts of nose shape were supposed to be under discussion, it’s hard to say whether he feels results like these would pose any problems for his drift hypothesis.

Moving targets can be notoriously difficult to hit

While I still remain agnostic about the precise degree to which variation in nose shape has been the target of selection, as I’m by no means an expert on the subject, the larger point here is how useful adaptationist research can be. It’s not enough to just declare that variation in a trait is obviously the product of drift and not selection and leave it at that in much the same way that one can’t just assume a trait in an adaptation. As far as I see it, neither drift nor adaptation ought to be the null hypothesis in this case. Predictions need to be developed and tested against the available data, and the adaptationist paradigm is very helpful in generating those predictions and figuring out what data might be worth testing. That’s most certainly not to say those predictions will always be right, or that the research flowing from someone using that framework will always be good. The point is just that adaptationism itself is not the problem PZ seems to think it is.

References: Noback, M., Harvati, K., & Spoor, F. (2011). Climate-related variation of the human nasal cavity American Journal of Physical Anthropology, 145 (4), 599-614 DOI: 10.1002/ajpa.21523

PZ Myers: Missing The Mark

As this year winds itself to a close, I’ve decided to treat myself to writing another post that allows me to engage more fully in my debating habit. The last post I did along these lines dealt with the apparent moral objection some people have for taking money from the wrong person, and why I felt they were misplaced. Today, the subject will be PZ Myers, who, as normally seems to be the case, appears to still have a dim view of evolutionary psychology. In this recent post, PZ suggested that evolutionary psychology is rotten right down to its theoretical core because of an apparently fatal misconception: adaptationism. Confusingly, PZ begins his attack on this fatal misconception by affirming that selection is an important mechanism, essential for fully understanding evolution, and ought not be ignored by researchers. In essence, PZ’s starting point is that the fatal flaw of evolutionary psychology is, in addition to not being a flaw, a vital conceptual paradigm.

Take that?

If you’re looking for anything in this post about why adaptationism per se is problematic, or a comparison demonstrating that research in psychology that makes use of adaptationism is generally inferior to research conducted without that paradigm, you’re liable to disappointed by PZ’s latest offering. This is probably because very little of his post actually discusses adaptationism besides his praise of it; you know, that thing that’s supposed to be a seriously flawed foundation. So given that PZ doesn’t appear to actually be talking about adaptationism itself being a problem, what is he talking about? His main concern would seem to be that he feels that other evolutionary mechanisms – specifically, genetic drift and chance – are not as appreciated as explanatory factors as he would prefer. He’s more than welcome to his perception of whether or not some factors are under-appreciated. In fact, he’s even willing to share an example:

Most of the obvious phenotypic variation we see in people, for instance, is not a product of selection: your nose does not have the shape it does, which differs from my nose, which differs from Barack Obama’s nose, which differs from George Takei’s nose, because we independently descend from populations which had intensely differing patterns of natural and sexual selection for nose shape; no, what we’re seeing are chance variations amplified in frequency by drift in different populations.

While I currently have no strong hypotheses one way or another about past selections on nose shape, PZ certainly seems to: he feels that current variation in nose shape is obviously due to genetic drift. Now I know it might seem like PZ is advancing a claim about past selections pressures with absolutely no evidence; it also might seem like his claim makes no readily apparent testable predictions, making it more of a just-so story; it might even seem that these sort of claims are the kind that are relatively less likely to ever see publication for the former two reasons. In all fairness, though, all of that only seems that way because all those things happen to also be true.

Moving onto his next point, PZ notes that chance factors are very important in determining the direction evolution will take when selection coefficients are small and the alleles in question aren’t well-represented in the gene pool. In other words, there will be some deleterious mutations that happen to linger around in populations because they aren’t bad enough to be weeded out by selection, and some variations that would be advantageous but never end up being selected. This is a fine point, really; it just has very little to do with adaptationism. It has even less to do with his next point, which involves whether color preference has any functional design. Apparently, as an evolutionary psychologist, I’m supposed to have some kind of feelings about the matter of color preference by association, and these feelings are supposed to be obviously wrong. (If I’m interpreting PZ properly, that is. Of course, if I’m not supposed to share some opinion about color preference, it would be strange indeed for him to bring that example up…)

“Well, I guess I can’t argue with that logic…”

Unfortunately, PZ doesn’t get his fill of the Pop Anti-Evolutionary Psychology Game in this first go of collective guilt by association, so he takes another pass at it by asserting that evolutionary psychologists begin doing research by assuming that what they’re studying is a functional adaptation. For those unwilling to click through the link:

…[T]he “Pop Anti-Evolutionary Psychology Game.” Anyone can play…First, assert something that evolutionary psychologists think. These assertions can come in any of a number of flavors, the only requirement being that it has to be something that is obviously false, obviously stupid, or both…hyper-adaptationism is always a good option, that evolutionary psychologists assume that all traits are adaptations…The second part of the game should be obvious. Once you’ve baldly asserted what evolutionary psychologists believe…point out the blindingly obvious opposite of the view you’ve hung on evolutionary psychology.

This is, I think, supposed to be the problem that PZ was implying he had with evolutionary psychology more generally and adaptationism specifically. If this was supposed to be his point all along, he really should have put it at the beginning. In fact, had he simply written “not all traits and variations of those traits are adaptations” he could have saved a lot of time and been met with agreement from, of all people, evolutionary psychologists.

Breaking with tradition, PZ does mention that there have been some evolutionary psychology papers that he likes. I can only suppose their foundational concept was somehow different from the ones he doesn’t like. Confusingly, however, PZ also goes on to say that he tends to like evolutionary psychology papers more as they gets away from the “psychology” part of things (the quotes are his and I have no idea what they are supposed to mean), and focus more on genetics, which makes me wonder about whether he’s actually reading papers in the field he thinks he is…

“No; I’m not lost, and no, I won’t stop and ask for directions”

Finally, PZ ends his rather strange post by asserting that we can’t learn anything of importance evolutionarily from studying undergraduates (which isn’t a novel claim for him). I’m most certainly in favor of research with more diverse cross-cultural samples, and moving beyond the subject pool is a good thing for all researchers in psychology to do. The assertion that we can’t learn anything of value from this sample of people strikes me as rather strange, though. It would be nice, I suppose, if PZ could helpfully inform us as to which types of people we could potentially learn important psychological things from, what kind of important things those might be, and why those things are specific to those samples, but I suspect he’s saving that wisdom up for another day.

Are Associations Attitudes?

If there’s one phrase that people discussing the results of experiments have heard more than any other, a good candidate might be “correlation does not equal causation”. Correlations can often get mistaken for (at least implying) causation, especially if the results are congenial to a preferred conclusion or interpretation. This is a relatively uncontroversial matter which has been discussed to death, so there’s little need to continue on with it. There is, however, a related reasoning error people also tend to make with regard to correlation; one that is less discussed than the former. This mistake is to assume that a lack of correlation (or a very low one) means no causation. Here are two reasons one might find no correlation, despite underlying relationships: in the first case, no correlation could result from something as simple as there being no linear relationship between two variables. As correlations only measure linear relationships, distributions that resemble bell curves would tend to yield correlations equal to zero.

For the second case, consider the following example: event A causes event B, but only in the absence of variable C. If variable C randomly varies (it’s present half the time and absent the other half), [EDIT: H/T Jeff Goldberg] you might end up with no correlation, or at least a very reduced one, despite direct causation. This example becomes immediately more understandable if you relabel “A” as heterosexual intercourse, “B” as pregnancy, and “C” as contraceptives (ovulation works too, provided you also replace “absence” with presence). That said, even if contraceptives aren’t in the picture, the correlation between sexual intercourse and pregnancy is still pretty low.

And just in case you find that correlation reaching significance, there’s always this.

So why all this talk about correlation and causation? Two reasons: first, this is my website and I find the matter pretty neat. More importantly, though, I’d like to discuss the IAT (implicit association test) today; specifically, I’d like to address the matter of how well the racial IAT correlates (or rather, fails to correlate) with other measures of racial prejudice, and how we ought to interpret that result. While I have touched on this test very briefly before, it was in the context of discussing modularity; not dissecting the test itself. Since the IAT has recently crossed my academic path again on more than one occasion, I feel it’s time for a more complete engagement with it. I’ll start by discussing what the IAT is, what many people seem to think it measures, and finally what I feel it actually assesses.

The IAT was introduced by Greenwald et al in 1998. As per its namesake, the test was ostensibly designed to do something it would appear to do fairly well: measure the relative strengths of initial, automatic cognitive associations between two concepts. If you’d like to see how this test works firsthand, feel free to follow the link above, but, just in case you don’t feel like going through the hassle, here’s the basic design (using the race-version of the test): subjects are asked to respond as quickly as possible to a number of stimuli. In the first phase, subjects will view pictures of black and white faces flashed on the screen and asked to press one key if the face is black and another if it’s white. In the second phase, subjects will do the same task, but this time they’ll press one key if the word that flashes on the screen is positive and another if it’s negative. Finally, these two tasks are combined, with subjects asked to press one key if the face is white or the word is positive, and another key if the face is black or the word is negative (these conditions then flip). Different reaction times in this test are taken to be measures of implicit cognitive associations. So, if you’re faster to categorize black faces with positive words, you’re said to have a more positive association towards black people.

Having demonstrated that many people seem to show a stronger association between white faces and positive concepts, the natural question arises about how to interpret these results. Unfortunately, many psychological researchers and laypeople alike have taken a unwarranted conceptual leap: they assume that these differential association strengths imply implicit racist attitudes. This assumption happens to meet with an unfortunate snag, however, which is that these implicit associations tend to have very weak to no correlations with explicit measures of racial prejudice (even if the measures themselves, like the Modern Racism Scale, are of questionable validity to begin with). Indeed, as reviewed by Arkes & Tetlock (2004), whereas the vast majority of undergraduates tested manifest exceedingly low levels of “modern racism”, almost all of them display a stronger association between white faces and positivity. Faced with this lack of correlation, many people have gone on to make a second assumption to account for this lack, that assumption being that the implicit measure is able to tap some “truer” prejudiced attitude that the explicit measures are not as able to tease out. I can’t help but wonder, though, what those same people would have had to say if positive correlations had turned up…

“Correlations or no, there’s literally no data that could possibly prove us wrong”

Arkes & Tetlock (2004) put forth three convincing reasons to not make that conceptual jump from implicit associations to implicit attitudes. Since I don’t have the space to cover all their objections, I’ll focus on the key points of them. The first is one that I feel ought to be fairly obvious: quicker associations between whites and positive concepts are capable of being generated by merely being aware of racial stereotypes, irrespective of whether one endorses them on any level, conscious or not. Indeed, even African American subjects were found to manifest pro-white biases in these tests. One could take those results as indicative of black subjects being implicit racist against their own ethnic group, though it would seem to make more sense to interpret those results in terms of the black subjects being aware of the stereotypes they did not endorse. The latter interpretation also goes a long way towards understanding the small and inconsistent correlations between the explicit and implicit measures; the IAT is measuring a different concept (knowledge of stereotypes) than the explicit measures (endorsement of stereotypes).

In order to appreciate the next criticism of this conceptual leap, there’s an important point worth bearing in mind concerning this IAT: the test doesn’t measure where two concepts are associated in any sense whatsoever; it merely measures relative strengths of these associations (for example, “bread” might be more strongly associated with “butter” than it is with “banana”, though it might be more associated with both than with “wall”). This importance of this point is that the results of the IAT do not test whether there is a negative association towards any one group; just whether one group is rated more positively than another. While whites might have a stronger association with positive concepts than blacks, it does not follow that blacks have a negative association overall, nor that whites have a particularly positive one either. Both groups could be held in high or low regard overall, with one being slightly favored. In much the same way, I might enjoy eating both pizza and turkey sandwiches, but I would tend to enjoy eating pizza more. Since the IAT does not track whether these response time differentials are due to hostility, these results do not automatically seem to apply well to most definitions of prejudice.

Finally, the authors make the (perhaps politically incorrect) point that noticing behavioral differences between groups – racial or otherwise – and altering behavior accordingly is not, de facto, evidence of an irrational racial biases; it could well represent the proper use of Bayesian inference, passing correspondence benchmarks for rational behavior. If one group, A, happens to perform behavior X more than group B, it would be peculiar to ignore this information if you’re trying to predict the behavior of an individual from one of those groups. In fact, when people fail to do as much in other situations, people tend to call that failure a bias or an error. However, given that race is touchy political subject, people tend to condemn others for using what Arkes & Tetlock (2004) call “forbidden base rates”. Indeed, the authors report that previous research found subjects were willing to condemn an insurance company for using base rate data for the likelihood of property damage in certain neighborhoods when that base rate also happened to correlate with the racial makeup of that neighborhood (but not when those racial correlates were absent).

A result which fits nicely with other theory I’ve written about, so subscribe now and don’t miss any more exciting updates!

To end this on a lighter, (possibly) less politically charged note, a final point worth considering is that this test measures the automaticity of activation; not necessarily the pattern of activation which will eventually obtain. While my immediate reaction towards a brownie within the first 200 milliseconds might be “eat that”, that doesn’t mean that I will eventually end up eating said brownie, nor would it make me implicitly opposed toward the idea of dieting. It would seem that, in spite of these implicit associations, society as a whole has been getting less overtly racist. The need for researchers to dig this deep to try and study racism could be taken as heartening, given that we, “now attempt to gauge prejudice not by what people do, or by what people say, but rather by millisecs of response facilitation of inhibition in implicit association paradigms” (p.275). While I’m sure there are still many people who will make a lot about these reaction time differentials for reasons that aren’t entirely free from their personal politics, it’s nice to know just how much successful progress our culture seems to have made towards eliminating racism.

References: Arkes, H.R., & Tetlock, P.E. (2004). Attributions of implicit prejudice, or “Would Jesse Jackson ‘fail’ the implicit association test?” Psychological Inquiry , 15, 257-278

Greenwald, A.G., McGhee, D.E., & Schwartz, J.L.K. (1998). Measuring individual differences in implicit cognition: The implicit association test. Journal of Personality and Social Psychology, 74, 1464-1480