Monday 29 July 2013

Some Thoughts on PZ vs. Pinker

PZ Myers was recently part of a panel on Evolutionary Psychology (EP) at the science fiction and fantasy convention CONvergence. A number of people involved in EP have criticised PZ's account of EP, (see the articles here, here and here, as well as earlier posts on this blog as examples) Jerry Coyne and Steven Pinker amongst them.

PZ has answered Coyne and Pinker and I find his answers continue to mislead people about what Evolutionary Psychologists actually suggest and study. I am not particularly interested in his post answering Jerry Coyne, save to say it says nothing pertinent about the field. In short PZ accuses Coyne of a "dignified retreat" (by which I take him to mean people talking more carefully and conservatively to hostile audiences than friendly ones - I will get to this later, save to say I feel PZ is guilty of the same and that he strangely identifies Coyne as providing "a perfect example" of the sort of dignified retreat he feels evolutionary psychologists perform, this being odd as Jerry is not an evolutionary psychologist), bemoans Coyne's occasional descent into ad hominem (I hear that if you live by the sword you die by the sword) and generally says nothing about EP beyond the same strawman stuff he said in the talk.

However his post Tackling Pinker's defense of Evolutionary Psychology is more interesting, though no less misleading.

A note on colour coding. Green text is stuff from the Coyne/Pinker defence or other EP sympathisers, orange text PZ and grey text is me (I'm aware of the semiotic implications of assigning green to allies and orange to opponents - forgive me).

If you can't be bothered to read on the short version is: I disagree with pretty much everything PZ says, I think it's clear he hasn't much of an idea how psychology works, let alone how EP works. I concede that Steven Pinker gave too glib a response to qualms about studies being performed mainly on college students, but that to concentrate on this this misses a bigger picture that I hope to illustrate.

Another short note: If anyone wants to bring this to PZ's attention feel free, but I won't be bothering myself because it's clear to me that he isn't listening. This is for my own education and anyone else who might be genuinely interested.

After some contextual preamble PZ begins:

I dislike evolutionary psychology.

Now this is mostly an irrelevance, but isn't this a "dignified retreat"? Seems to me PZ is much happier to use harsher language in safer territory. For example according to this transcript of the CONvergence talk his words were...

My bias is, I despise [EP].

...and the rest of his input in that arena seemed consistent with that tone.

Now whilst I think this is a clear example of the sort of "dignified retreat" PZ condemns in others I don't mention it merely to highlight his hypocrisy, but to bring up something that will be a recurring theme: yes, we do talk more confidently in front of friends than we do critics, and sometimes there are perfectly good reasons to do so. This will become important later on.

PZ moves on to quote Pinker responding to him:

Myers: Fundamental assumptions of evo psych: That you can infer an adaptive history from the distribution of current traits — that they are adaptations at all is an assumption usually not founded in evidence (this is not to deny that that there are features that are clearly the product of selection, but that you can’t pick an arbitrary attribute and draw elaborate scenarios for its origins). . .

Pinker: Of course “arbitrary” and “elaborate” are the straw-man giveaways here. What about carefully selected attributes, and minimal assumptions about phylogeny with a focus on function, as we do for other organs? You can ask what the spleen is for – and it would be perverse to do physiology without asking such a question – without “drawing elaborate scenarios for its origins.”

To which PZ says:

Whoa, whoa, whoa — that skips right over the really important word: “adaptive”. Start there. That’s my primary objection, the habit of evolutionary psychologists of taking every property of human behavior, assuming that it is the result of selection, building scenarios for their evolution, and then testing them poorly.

I have two important objections to this.

The first and most important objection: They. Don't. Do. This. To adopt Pinker's rhetoric, "every" and "poorly" are the straw-man giveaways here, as well as the implication that evolutionary scenarios are necessarily constructed prior to tests.

Evolutionary psychologists are perfectly aware that sociocultural factors, individual differences and neurological quirks are responsible for all sorts of human behaviour. They therefore focus, quite painstakingly in the main, on what can be shown to be cross-cultural propensities in human behaviour.

Now there's a second point, which may seem at odds with the first but which actually need not be.

It is arguably the main priority of evolutionary psychologists to account for what other perspectives in psychology have trouble explaining. It isn't so much that EP typically shoehorns evolutionary explanations onto psychological issues we already have concrete sociocultural/individual explanations for, it is when a sociocultural/individual explanation for behaviour falls short that a phenomena for which an evolutionary line of enquiry might be rewarding is indicated.

So the impression PZ seems keen to give is that evolutionary psychologists chose any old behaviour (arbitrarily), ignore conflicting accounts and make up some kind of shoddy demonstration of a phenomena they have decided upon from the outset.

Whilst I cannot deny the existence of inept and/or corrupt practitioners (can any field?) I feel a fairer summary is that they are well aware of phenomena for which there are solid explanations and concentrate on those which seem to be propensities throughout the species (and sometimes throughout other species too) and test them to standards in-line with those of social science generally.

He continues:

The bulk of the genetic foundation of our psychology (and I agree that there must be one!) must be byproducts and accidents. The null hypothesis of evolutionary psychology should be that a behavior is non-adaptive, yet for some reason all I ever see is adaptive hypotheses.

The spleen is an interesting example. There are components of the spleen that are definitely functional and almost certainly adaptive: its functions as a blood reservoir, as an element of the immune system, as part of the erythrocyte cycling mechanism. You can examine the evolution of those functions phylogenetically; for instance, some teleosts lack the erythropeotic functions of the spleen, while the majority use it as a blood reservoir. You can begin to dissect its history comparatively, by looking at what has a clear functional role and looking at the pattern of emergence of those properties.

What you can’t do is pick any particular property of the spleen and invent functions for it, which is what I mean by arbitrary and elaborate. For instance, the spleen is located in most people in the upper left quadrant of the abdomen; are you going to make an adaptive case for why it’s on the left rather than the right? The actual reason almost certainly has nothing to do with adaptation or selection, and everything to do with historical and developmental mechanisms that are neutral with respect to selection.

Would I make an adaptive case for why the human spleen tends to be on the left rather than the right? No, but I think a strong adaptive case can be made for why it's in the abdomen rather than the head. Now I know little about the spleen aside from it's size and main functions, but I doubt it's either arbitrary or elaborate to suggest that the reason it's in the abdomen is because there are fewer costs to the organism it being there than elsewhere.

So whilst it's naïve to assume certain things about it's position, it doesn't seem naïve to assume other things about it's position. Does it matter if it's on the left or right? I doubt it. Does it matter that it's not on the end of my nose? I think so.

Given that they are talking in general terms I don't suppose there's much more to be said about the spleen analogy. However, Pinker's point was not that there wasn't something about the spleen that might be down to chance, but that there were apparent functions about which we can make assumptions that are based in sound reasoning.

Including some things about its position.

So I think PZ misses the point here. Perhaps he can hold up individual studies that really do make arbitrary judgements and construct elaborate scenarios to justify them (again, show me a field without dodgy practitioners). Pinker's point is that representative studies put in a lot more thought and discipline than PZ gives credit to.

PZ moves on to Pinker's next defence:

Myers:. . . That behavioral features that have been selected for in our history are represented by modular components in the brain – again with rare exceptions, you can’t simply assign a behavioral role to a specific spot in the brain, just as you can’t assign a behavior to a gene.

Pinker: No one in Ev Psych points to specific spots in the brain – that’s cognitive neuroscience, not evolutionary psychology. The only assumption is that there are functional circuits, in the same way that a program can be fragmented across your hard drive.

To which PZ responds:

Now this is one of my peeves with evolutionary psychology. The evo psych literature is thick with papers emphasizing “modularity”; that evolutionary psychology FAQ I referenced before makes it clear that it’s an important concept in the field (and also ties it to concepts in computer science). Yet it is meaningless. Sometimes there’s the implication that the “module” is a discrete element in the brain, but it’s never clear whether they’re talking about a genetic module (an epistatic network of genes) or a neural module (an interconnected network of neurons), and when pressed, they retreat, as Pinker does here, to an admission that it could be just about anything scattered anywhere in the brain.

Interesting to note that he is aware of the FAQ. I will bring this up again later on.

Anyway - No it's not meaningless, it's confusing maybe, but not meaningless.

What seems to often get lost in these discussions is that psychologists study behaviour first and foremost. Given that evolutionary psychologists are overwhelmingly materialists (in the philosophical sense) it stands to reason that the root cause of behaviour resides in the brain/nervous system in the form of electrochemical stimulus acting on physical bits of the brain and body.

So can you show someone a phenomena like a memory or a heuristic in the brain? Well I don't know, but as a materialist I would say that at some level you could, that "this nerve doing this as these synapses do that and reaching these areas equals a certain feeling or thought" isn't a naïve notion. However, it isn't how psychologists demonstrate things like memories or heuristics, they do so via experimentation, brain imaging, studying the effects of brain injury and disorder, and so on.

I think this sort of thing (ability to recall a memory, effect of a heuristic) is what Pinker means by a functional circuit.

Now many such circuits are built largely as a result of environmental inputs, but not all are. They certainly all rely on innate structures.

If that is accepted then what is there to say that it is naïve to assume that certain propensities to behaviour are innate to neurotypical human minds? All such things must be partially, mostly or wholly innate.

Evolutionary psychologists tend to call those processes that they are confident to be largely or wholly innate mental modules.

PZ says he is unclear whether this means a genetic module or a neural module.

Neither. It's an innate behavioural process. There is presumably a neural network that lies behind the process (and depending on the behaviour in question there is more or less evidence to demonstrate such a thing). Given that it is innate there must be a genetic basis to the neural network which supports the process (and certain neurology with heritable components provide evidence of this, like autism and theory of mind).

So in order to resolve the confusion there are three levels of understanding:

1) They are looking at a bit of behaviour (a psychological process for which there is a demonstrable propensity in humans).
2) It stands to materialist reason that part(s) of the brain are involved - a neural network.
3) Because it's thought to be innate it stands to reason that genetic factors influence (if not outright dictate) the building of the network.

Is Pinker engaged in a retreat? As far as I can see it his attitude has been consistent for last 16 years or so judging from "How the Mind Works" in which he talks of modules in much the same way he does here. For example:

The word "module" brings to mind detachable, snap-in components, and that is misleading. Mental modules are not likely to be visible to the naked eye as circumscribed territories on the surface of the brain, like the flank steak and the rump roast on the supermarket cow display. A mental module presumably looks more like roadkill, sprawling messily over the bulges and crevasses of the brain. Or it may be broken into regions that are interconnected by fibres that make the regions act as a unit. The beauty of information processing is the flexibility of its demand for real estate. Just as a corporation's management can be scattered across sites linked by a telecommunications network, or a computer program can be fragmented into different parts of the disk or memory, the circuitry underlying a psychological module might be distributed across the brain in a spatially haphazard manner - How the Mind Works page 30.

The only thing Pinker "retreats" from is the position PZ assumes evolutionary psychologists adopt - a position Pinker (and most evolutionary psychologists) never held.

So my question is…why talk about “modules” at all, other than to reify an abstraction into something misleadingly concrete?

It's the jargon the practitioners have decided upon for phenomena they deem less abstract than PZ does (I also recommend the response given to this query here).

Evolutionary psychologists don’t do neurobiology, and they don’t do genetic dissections, and they don’t do molecular genetics, so why do they insist on modularity?

Asides from the reasons already stated - some evolutionary psychologists do do such things, or work alongside those who do.

It’s premature and a violation of Occam’s razor to throw the term around, and also completely unnecessary — a behavior could be a product of diffuse general phenomena in the brain without diminishing its importance at all.

Is it necessarily a violation of Occam's razor to assume that "important" propensities in behaviour have not resulted from selective processes in part or in whole? Seems counter-intuitive to me.

As for "a behaviour could be a product of diffuse general phenomena..." yes, it could, and the concept of modules covers that if it is properly understood.

Back to Pinker's defence:

Myers: . . . That the human brain is adapted to a particular environment, specifically the African savannah, and that we can ignore as negligible any evolutionary events in the last 10,000 years, that we can ignore the complexity of an environment most of the evo psych people have never seriously studied, and that that environment can dictate one narrow range of outcomes rather than permit millions of different possibilities.

Pinker: The savannah is a red herring – that’s just a convenient dichotomization of the relevant continuum, which is evolutionary history. A minimal commitment to “pre-modern” gives you the same conclusions. By saying that the brain could not have been biologically adapted to stable government, police, literacy, medicine, science, reliable statistics, prevalence of high-calorie food, etc., you don’t need to go back to the savannah; you just need to say that these were all relevantly recent in most people’s evolutionary history. The savannah is just a synechdoche.

To which PZ says:

Ah, a synechdoche. This is the evolutionary psychology version of the religious argument that it’s “just a metaphor.”

Again, this is a peeve I have with the field. I agree with the general principle that of course the brain is a product of our evolutionary history, and that there is almost certainly a foundation of genetically defined, general psychological properties of the mind…and that a great many specific psychological properties are not biologically adapted. Pinker is writing good common sense here.

But over and over, you see evolutionary psychologists falling into this trap of examining a behavior and then fitting it to some prior specific environment. They talk of a Savannah Mind or they generalize it to the Environment of Evolutionary Adaptedness. It’s another reification of the unknown. You don’t like “savannah”? Change it to “Pleistocene”. It’s just as broad and meaningless. It’s an attempt to reduce the complex and diverse to a too simple unit.

Yes, it's a reification of the "unknown" (some of the phenomena in question are better understood than others, of course) ... based on the available evidence and undertaken according to the standards of social science. There are better ways of thinking about it than "Savannah Mind" in my opinion ("Pleistocene Mind" would be better), but better still is the understanding that notable change in the Holocene is tentatively ruled out. However, silly as these notions might seem on face value they are based on paucity of evidence to the contrary. If you want to overturn them show us the innate behavioural propensity that has arisen in the interim or show us the innate psychological distinctions between populations that haven't had much contact during the Holocene.

Can't do it? Neither can I.

That's why I accept that in terms of our innate behavioural propensities the Holocene is of no particular consequence. Do some such propensities speak to life in Africa? Yes, and they need examining and criticising individually and on their own terms.

To further the point - my understanding is that Australian aborigines were effectively genetically isolated throughout the Holocene until the arrival of Captain Cook, so what innate psychological differences to other humans do they display? "None" is the received wisdom here, hence the contention.

So pointing out that "Savannah Brain" is a metaphor is not like a religious "just a metaphor" argument. It's more like pointing out that "survival of the fittest" as a shorthand for the process of natural selection is figurative to a degree. It's a useful summary for those who know what they mean and where the limits are, but can be misleading if taken too literally.

Pinker's point then is not that evolutionary psychologists do not use the term and pursue related lines of enquiry, but that PZ once again attacks a strawman with arguments like "...the human brain is adapted to a certain environment, specifically the African savannah...". No, certain behavioural propensities seem suited to an ancestral African environment, even among those who have never lived in such a place, but not all.

Next:

Myers: I’d also add that most evo psych studies assume a one-to-one mapping of hypothetical genes to behaviors. . .

Pinker: Completely untrue – this was Gould’s claim in the 1970s, which confused a “gene for x” (indispensable in any evolutionary thinking, given segregation) in the sense of “increases the probability of X, averaging over environments and other genes” with “a gene for X” in the sense of “necessary and sufficient for X.” Every honest biologist invokes “gene for X” in the former sense; evolution would be impossible if there were no additive effects of genes. No one believes the latter – it’s pure straw.

To which:

By one-to-one, I mean the assumption that a behavior trait can be mapped to a contribution from a gene that was subject to selection for that trait; that it might be an additive property of a pleiotropic gene will be nominally noted, as Pinker does here, but operationally ignored. Remember, the issue is not whether genes contribute to our psychology, a point I totally agree with, but whether we can assign a selective origin to a behavior. That is a much, much harder problem.

Ah! This looks to me like a dignified retreat.

People look to PZ as an educator - his students (who he advises not to show interest in EP), those who read his blog, those who attend his speaking engagements. When he means "they reckon certain behaviours are innate and therefore influenced by our genes" perhaps he should say "they reckon certain behaviours are innate and therefore influenced by our genes". Because that's a more modest claim than "they assume one-to-one mapping of genes to behaviours", which is nonsense.

By the way, whoever said these problems weren't hard?

The next part of Pinker's defence.

Myers [continuation of previous sentence]:. . . and never actually look at genes and for that matter, ignore most human diversity to focus on a naive typological simplicity that allows them to use undergraduate psych majors at Western universities as proxies for all of humanity”

Pinker: It’s psychologists, not evolutionary psychologists, who focus on Western undergrads –field research and citations of anthropology are vastly more common in ev psych than in non-ev-psych. PZ is engaging in prosecution here, not analysis – he’s clearly ignorant of the sociology of the fields.

To which PZ responds:

First, this has already been addressed by Stephanie Zvan: when you look in the evolutionary psychology journals at papers identified as evolutionary psychology, you find…a focus on Western undergrads. I throw up my hands in exasperation. Look at the actual work done in your field, not the abstract ideal you hold in your head. I get my vision of evolutionary psychology by reading the papers.

I have some sympathy for PZ here but I think he missed the point (again). Pinker could have made it clear that the vast majority of studies into psychology begin with experiments in universities on participants who are overwhelmingly students (of psychology, no less).

But in coming to an understanding of any given phenomena this is usually acknowledged by those in the field as a tentative first step. Most studies in psychology won't be taken seriously until they have been replicated, replicated with different sorts of participants, contrasted to similar experiments with different independent variables and so on.

And with this taken on board Pinker is right, studies in EP do tend to make greater use of field work and anthropological studies, even cross-species studies, in relation to psychology in general.

Does a focus on western undergrads remain? By necessity yes (I urge those reading Stephanie's post to check out ChasCPeterson's comments, in fact I recommend his comments on this subject in general).  However conclusions from such studies will tend to be tentative until further studies are performed showing that the behavioural patterns hold true across cultures (and sometimes even species).

Generally when it comes to social science I find the notion that you can get a good perspective from reading papers to be erroneous. No one study or experiment can account for all the variables to produce a solid conclusion. Critics such as PZ and Stephanie are almost always going to be able to rip apart a single study provided they ignore the body or work that it's in dialogue with.  It is meta-analyses and text books that give you a firm grounding in the subject, from there you can properly appreciate the strengths and weaknesses of any given study. It is also poorly understood that those writing psychological studies are encouraged to make tentative conclusions and then follow up with a speculative analysis. This does seem to be something that causes confusion.

As Pinker says PZ seems ignorant of the sociology of the fields, and I think this is clear from his conflation of EP (if not psychology) with neuroscience.

It's also worth taking some time to read this defence of the pertinence of WEIRD studies by Ed Clint.

Pinker (I think, or it may be Coyne) also states:

As for diversity – is he arguing for genetic differences among human groups, a la Herrnstein & Murray?

To which PZ says:

Secondly, what a weirdly off-target attempt at ad hominem.

This is tangential, but I don't think it was ad hominem. It was a question that resulted from the statement "...they ignore most human diversity..." and seeing as we are talking about psychology the response was therefore pertinent (it certainly popped into my head as I hope previous blog posts demonstrate). Where is there diversity in innate psychological propensity or capacity between human populations?

Once again, my criticisms are being addressed by imagining motives; in Jerry Coyne’s critique, I’m an uber-liberal offended at the consequences a genetic component to behavior might have on my egalitarian biases; now Pinker takes a swipe by tarring me with the likes of Herrnstein & Murray. Make up your minds!

Why is Pinker assumed to duplicate Coyne's apparent opinion on the matter? They are different people are they not? Presumably PZ is ignorant of Pinker's defence of Herrnstein in "The Blank Slate" (though I will point out he hasn't offered a similar defence of Murray).

Anyway, PZ does sort of answer the question:

For the record, of course there are genetic differences in human populations! It’s an open question whether any of them make significant contributions to human psychology, however. I’m open to evidence either way.

Which makes it all the more confusing as to why PZ moaned about evolutionary psychologists ignoring human diversity. They (as a gestalt) have looked hard for evidence of differences in innate psychological propensities in different human populations. They have yet to find any. Therefore the contention is that there isn't any pending further developments.

I mean, this is discussed prominently in the same EP FAQ PZ claimed to have read earlier.

But my remark was about cultural diversity (which also, by the way, exists).

I'm going to try and avoid hyperbole here, but I reckon if I had a tenner for every time I've seen Steven Pinker acknowledge the existence of sociocultural influence I could buy a brand new American Standard Telecaster.

Last time I looked they were about £500.

I think it's important to note here that not all sociocultural differences rule out evolutionary explanations for behaviour. Some of them even indicate it. For example Inuit people living near the north pole wear more clothing than equatorial bushmen. This is a sociocultural phenomenon. However the behaviour is clearly informed by the fact that humans don't like to feel too hot or too cold, to which our natural history is pertinent.

Setting aside the notion of a genetic component for now, we know that culture creates different minds. How can you analyze the causes of a behavior if your work focuses on a relatively uniform sample?

Easy - by making only the most tentative of judgements about said behaviour until similar studies on different sets and types of participants are conducted.

Anyway, last bit:

Myers: Developmental plasticity vitiates most of the claims of evo psych. Without denying that some behaviors certainly have a strong biological basis, the differences in human behaviors are more likely to be a product of plasticity than of genetic differences. . .

Pinker: Plasticity is just learning at the neural level, and learning is not an alternative to innate motives and learning mechanisms. Plasticity became an all-purpose fudge factor in the 1990s (just like “epigenetics” is today). But the idea that the brain is a piece of plastic molded by the environment is bad neuroscience. I reviewed neural plasticity in the chapter “The Slate’s Last Stand” in The Blank Slate, with the help of many colleagues in neuroscience, and noted that the plasticity that allows feedback during development and learning during ontogeny is superimposed on an innate matrix of neural organization. For example if you silence *all* synaptic activity in the brain of a developing mouse with knock-outs, the brain is pretty much normal.

PZ replies:

Speaking of straw men…I found The Blank Slate entirely unreadable, unlike most of Pinker’s books, because of the gigantic straw man erected in the title. This flailing against me is a product of this weird idea that I reject the contribution of our genes to our minds, but just as there are no evolutionary psychologists who believe everything in our brains is genetically predetermined, there is no such thing in serious science as a “blank slater”.

Elsewhere PZ claims to have read the book. Seems odd not to read it because of the title. Personally I think it's the most readable of Pinker's books. I've never had problems with parsing a book because of the title. Just me?

This seems to be another dignified retreat. Remember the things PZ said that provoked this defence:

Plasticity is everything.

How does that differ from notions of a blank slate?

But it's by the by. The Blank Slate wasn't written about PZ. To be frank this seems like projection. Perhaps PZ sees himself as something of an heir to Gould, who Pinker is critical of from time to time. This isn't mere conjecture on my part - if you contrast PZs complaints in the CONvergence talk with those Gould gave EP they deal with the same sort of subjects (for example PZ and Gould both think the existence of writing poses a problem for the sort of modularity proposed by EP - it does not).

There is a continuum, and we’re arguing about degrees. For example, take a child of French parents and raise them in the United States, they’ll grow up speaking fluent English (or Spanish, depending on the household), and vice versa — an American child raised in France will speak French like a native. There is no genetic component to the details of language. Yet when you compare diverse languages you can start to pick out commonalities, and when you look at the neural substrates of language you do see shared anatomy and physiology — I do not hesitate to accept that there is an evolved component of human language. The differences between speakers are learned, the universals may well be biological.

Yeah fair enough, I mean the only thing missing from this bit is an acknowledgement that this is exactly the sort of thing evolutionary psychologists acknowledge.

Which means that when evolutionary psychologists try to parse out variations between different groups, racial or sexual, I suspect it’s most likely that they are seeing cultural variations, so trying to peg them to an adaptive explanation is an exercise in futility. When evolutionary psychologists try to drill down and identify the shared components, I’m much more willing to see their efforts as interesting.

Once again the assumption is made that it is somehow representative of EP to stress psychological differences between races. Talking gestalt - the exact opposite is true. If we moderns are psychologically equivalent to people of 12,000 years ago it stands to reason that we are psychologically equivalent to each other. In fact it is the confidence that we are psychologically equivalent to each other that leads to the notion that we are psychologically equivalent to those of the late Pleistocene.

Sex differences seem to be the elephant in the room, as evolutionary psychologists do propose a number of them. They are usually careful to discuss those that are demonstrated cross culturally (and sometimes cross-species).

Whilst I imagine no amount of reassurance in regard to the examination of sex differences will convince all critics that EP isn't somehow opposed to women's liberation I will trot out what I see as the party line on the matter. Such differences are small and statistical. They are matters of overlapping distribution. Nothing in EP rules out the notion that an individual of either sex might be well suited (or even optimal) in a job or social role typically associated with the opposite sex. A man might be a better communicator than most women despite noted trends to the contrary, a woman might be more inclined to bloody violence than most men despite noted trends to the contrary, and so on.

After this PZ engages Pinker over his anecdote about the mouse. I won't quote it all because it's lengthy and based around another apparent misconstruction of Pinker's point. I feel that it is summed up with the paragraph:

Try raising a child without contact with other humans. I guarantee you that their brains, when physically examined, would look “pretty much normal”…but does anyone really believe that psychologically, on the level evolutionary psychologists study brains, that they’d be “pretty much normal”?

Obviously not.

But if it were a typical baby would it still display certain propensities? Avoid the edges of cliffs? Display certain emotions? Cry when scared? Feel hunger? Abhor the smell of excrement? Develop a theory of mind between the ages of 3 and 5? Respond to a smile? And so on...

Pinker's anecdote was to show that environmental input has negligible impact on the structure of the brain (I anticipate objections such as presence of poisons or denial of nutrition, so these things aside). Therefore we know that genes order the brain. The argument regards what content they supply it with.

This is “pretty much normal” behavior from evolutionary psychologists, though. Point out that that their inferences about neuronal circuitry are bogus, they tell you that they don’t study neurons anyway; tell them that the behaviors they study are awfully plastic and flexible, and presto, hey, look, brains and neurons are patterned by genetic elements. The sleight of hand is impressive, except when you realize that science shouldn’t be about magic tricks.

Asking critics to understand the nuances behind the jargon they criticise is not an attempt at chicanery.

Tuesday 9 July 2013

CONvergence Panel on EP - Part Two.

This is part two of my comments on the CONvergence panel on Evolutionary Psychology. Starting again from the 30 minute mark.

Stephanie (I think) mentions that the panel have just been looking at the “good” EP so far, and have yet to get to the bad. This causes some laughter, which I can understand seeing as aside from a couple of concessions from Indre no one has had a good word to say about it.

I’ll just stop here to list a couple of the major sections of evolutionary psychology books I have read, including the course text set by the Open University.

Theory of Mind – Prominently featured in the university text and a number of pop-science books and introductory guides I looked at on the subject. Theory of mind refers to our ability to judge what others might be thinking. Clearly a highly adaptive trait and one that does seem to carry heritable components. A lot of work has been carried out comparing the ability of chimps and other great apes to perform skills associated with theory of mind.

Mentions by the panel: Zero.

Reciprocal Altruism - Prominently featured in the university text and a number of pop-science books and introductory guides I looked at on the subject. Essentially the notion explored in The Selfish Gene and similar books that basic morality may have arisen evolutionarily.

Mentions by the panel: Zero.

Common or Universal Emotional Responses and Phobias – Again, mentioned in every book I’ve read on the subject.

Mentions by the panel: Zero.

Mental Modules – Mentioned by some of the texts I have on the subject.

Mentions by the panel: Assumed to be the core of evolutionary psychology, and mischaracterised as parts of the brain rather than processes and cognitive shortcuts.

"Pleistocene Brain" – Mentioned by some of the texts I have on the subject, often in quite tentative terms.

Mentions by the panel: Assumed as a core of evolutionary psychology, and mischaracterised as a matter of closed debate (it isn’t).

An audience member asks a question about sex differences. I think it’s Stephanie who answers. She says that sex differences are largely cultural and not biological.

I doubt she’d receive any argument from most evolutionary psychologists, who would be happy to cede that the vast majority of observed differences between the sexes are sociocultural, and that changing culture affects even those differences which are thought to have a hereditary component.

Indre mentions that an example of behaviours changing over time would be the attitudes boys and girls have towards education. This is not a notion that has been challenged by evolutionary psychologists as far as I know. Generally it is attitudes towards violence, communication style, childcare and reproduction that are thought to be demonstrable cross-culturally in line with evolutionary psychology.

Indre mentions that the studies into men’s and women’s brains show less divergence on average than between given individuals of the same sex. I’m not sure if this means she admits to there being ways in which the average male brain differs from the average female brain, but it’s still rather by the by because evolutionary psychology focuses on behaviour, not the brain.

PZ tells an anecdote about having been involved in similar comparative studies, and he seems to say that they did find statistical differences between the brains of men and women. He puts this down to sociocultural impacts, which is convenient. Even if you find this line of argument convincing it’s still rather by the by because evolutionary psychology focuses on behaviour, not the brain.

Stephanie (I think) provides a hypothesis that patterns of women’s achievement in education may be economically driven. In itself a fair point, but by the by for the aforementioned reasons. The only psychologists who don’t admit to overwhelming cultural impact are bonkers psychologists.

Greg talks for a while, he reinforces the same point about variations and the overwhelming impact of sociocultural input. Again, I know of no evolutionary psychologist who would disagree.

He cedes that there is a particular sex difference that he recognises – that women outperform men in regards to certain types of communication. This is something evolutionary psychologists recognise and provide some insight on. Does he mention that? No.

Indre now talks about how hormones produce sex differences. Right she is. Does she talk about how this relates to evolution, or psychology, or evolutionary psychology? No.

The panel discuss why society is so fixated on gender issues. They think it’s because of the degree of investments people have in such things. No doubt this is true. Could any of these investments result from our natural history? They don’t say. Do they provide the perspective of evolutionary psychologists on the matter? No.

PZ brings up Evolutionary Psychology again, maybe he will discuss their attitudes to such matters. He just says that they are overly keen on trying to find an answer to things. I presume he means in the metaphysical sense, but I don’t know why being keen to find an answer is unbefitting a scientific approach.

Amanda reckons evolutionary psychologists are ignorant of the fact that marketers have had a major role to play in the notion that the colour pink is fit for a girl and blue for a boy, and that they have come up for reasons for why genes and hormones make boys prefer blue and girls prefer pink.

I know of one study, carried out by Professor Anya Hurlbert and Dr Yazhu Ling of Newcastle University that speculates loosely along such lines. Neither of them identify as evolutionary psychologists. Professor Hurlbert’s field is neuroscience. They cede that the only certain factor in colour preference is sociocultural, but speculate as to other factors including evolution. As far as I know their work has not made much positive impact on evolutionary psychologists. Whilst changes in tastes for fashion are clearly sociocultural they aren’t exclusive to notions of innate preference.

Indre talks about identity theory and how people like to categorise groups and that we tend to set these groups against one another. Is this something she thinks is innate or learned? She does not say. Might evolutionary psychologists have a perspective on notions of identity such as those demonstrated in Tajfel's minimal group studies? She does not say, she just reckons they are guilty of falling for the tendency in the pursuit of their own ideas.

I find this rather ironic, if there’s an in-group here it’s the panel, and the out-group being treated with undue dismissiveness are evolutionary psychologists.

I’m not sure what she says but Indre seems to mention that evolutionary psychologists are guilty of making pronouncements about different racial psychologies.

Now, do you remember that Pleistocene brain stuff that the panel seemed to find so amusing earlier?

That notion actually undermines a lot of racist opinions on the psychology of certain races, because if we have the same sort of psychological capacities as people in the late Pleistocene (“we” moderns as a group and “they” ancients as a group) then racist notions of how certain races made cognitive leaps in the interim are unsupported by evolutionary psychology (on the whole).

Now I don’t want to make too much of this, because the Pleistocene brain thing is held tentatively, and there could be notions of exception, and I know of a couple of practitioners who propose notions that I deem to be more or less racist.

But the field as a whole isn’t, and the reason for this is partly down to the (albeit tentative) notion that human minds have enjoyed their current capacities for A Long Time.

Bit of a mumble here – they mention studies into race and IQ. They don’t mention what role the field of evolutionary psychology plays in it. To repeat, on the whole it plays no role in it, and furthermore representative EP undermines it.

“Plasticity everywhere” pronounces PZ, he reckons that that is the take home message that is fatal to EP.

The take home message for PZ is clearly articulated in Steven Pinker’s discussion about PZ’s attitude to EP on Jerry Coyne’s blog.

Plasticity is just learning at the neural level, and learning is not an alternative to innate motives and learning mechanisms. Plasticity became an all-purpose fudge factor in the 1990s (just like “epigenetics” is today). But the idea that the brain is a piece of plastic molded by the environment is bad neuroscience. I reviewed neural plasticity in the chapter “The Slate’s Last Stand” in The Blank Slate, with the help of many colleagues in neuroscience, and noted that the plasticity that allows feedback during development and learning during ontogeny is superimposed on an innate matrix of neural organization. For example if you silence *all* synaptic activity in the brain of a developing mouse with knock-outs, the brain is pretty much normal.

Someone mentions that there are “quite a lot of evolutionary psychologists” who promote racism. No names are mentioned aside from the non-psychologist Andrew Sullivan. Talk then turns to the attitudes of the 19th century, about which I’m not sure evolutionary psychologists can fairly be blamed.

I don’t want to be flippant – I know there are racist ideas associated with the field. Even though I think that's an unfair association I don’t want to downplay how irritating it is or what sort of jeopardy it could present unchecked, and it is good to remain vigilant on that front. However, I don’t feel that such attitudes are prevalent or representative. Again - tentative notions of Pleistocene brains undermine a lot of racist theory.

Greg mentions Robert Picard as another of these people advancing racist notions. Is he an evolutionary psychologist? No. His field is journalism.

More on IQ follows – findings based on IQ are not something that evolutionary psychologists devote a lot of time to as far as I know. My experience may be atypical, but I was led to believe during my schooling in psychology that the field of psychometrics (of which IQ is the most famous) ought to be regarded as advancing tentative notions.

Greg mentions an anecdote about all studies into IQ between races going back to a particular study, and replicating its fatal flaws. I think that’s doubtful and besides, what has that to do with EP?

I think someone asks what the panel like about evolutionary psychologists.

PZ: That’s a really hard question.

Amanda (I think): I like the jokes actual biologists tell about them behind their backs.

Indre reckons they tell good stories that might lead onto testable hypotheses. OK. Who comes up with the hypotheses and the tests? Is it evolutionary psychologists, or do they just tell stories? She does not say.

Stephanie says evolutionary psychologists’ theories contradict one another, but does not give examples.

I think Amanda admits they have popularised the notion that evolution has had an impact on our psyches. Greg also cedes some “good stuff” but it’s such a begrudging mumble I can’t make much of it out. He seems to like the fact that they do studies with anthropologists from time to time.

PZ says he can categorically state that there are no good evolutionary psychologists because the premises so taint the field that it needs to be discarded. I hope anyone who reads this will agree that PZ demonstrates scant knowledge of their actual premises.

Amanda says she is often approached by evolutionary psychologists for a “debate”, and that she refuses but offers to forward them on to a biologist instead. She says they always back out at that point. No actual names are mentioned. If they are so easy to browbeat why didn't you invite one or two onto the panel?

PZ says he reckons evolutionary psychologists just aim stuff at the tabloid press. He also claims he has been convinced that women possess no maternal instinct, which strikes me as bizarre. Really - None?

There are then some more jokes.

Asked for last words Indre concedes that there will be more links found between genes and behaviour in years to come. Greg also seems a little more concessionary than earlier, but can’t hear him well enough to know what he's talking about in detail.

Thank you for coming and big round of applause - Huzzah!

Friday 5 July 2013

CONvergence Panel on EP - Part One.

Link to audio here - many thanks to Lousy Canuck:

http://freethoughtblogs.com/lousycanuck/2013/07/05/convergence-evolutionary-psychology-panel-audio/

These are some rough thoughts I had whilst listening to the first thirty minutes of the panel on evolutionary psychology at CONvergence. I find the sound quality makes it hard to understand 100% of what was said, so I won’t attempt a full transcription. I hope this is an accurate paraphrase of the content of the talk. Apologies in advance if anything is misconstrued.

Thoughts on the second half of the panel can be found here.


Introductions and Credentials
The first thing the members of the panel do is state who they are and provide their reasons for being there.

The moderator is Stephanie Zvan.

Indre Viskontas is a neuroscientist. She mentions that she has researched into memory.

PZ Myers also has qualifications in neuroscience, but is better known for evolutionary biology. Poor sound here – but he seems to state that he is opposed to evolutionary psychology.

Greg Laden is an anthropologist. He tells an anecdote about being taught by Leda Cosmides who is one of the key figures in the development of evolutionary psychology as a recognizable field.

Amanda Marcotte is a journalist and she states that she is there to be critical of the impact evolutionary psychology has in inspiring problematic narratives in the media.

Some commentators have noted that there isn’t an evolutionary psychologist on the panel – whilst I think that’s a shame it ought to be ceded that neuroscientists, evolutionary biologists and anthropologists certainly can have important things to say on the subject. My feeling at this point – however – is that no one on the panel is sympathetic to the field, and two of them already seem to have announced their antipathy. 

Definitions
The panel are then asked to give a definition of what evolutionary psychology is. Seems like a worthy exercise to start with. I’ll pause the recording here to think up my own:

Psychology is the study of human behaviour, and evolutionary psychology asserts that the process of evolution has been a primary factor in the shaping of that behaviour and discusses supporting evidence.

That’d be my attempt at a brief definition. I wonder if the panel will say anything like that?

Greg starts off. He says “the phrase means anything to do with evolutionary biology that has to do with human behaviour to a lot of people”. Good, a lot of people seem to be thinking on the right track.

However Greg does not think this is the case, he seems keen to promote the notion that Evolutionary Psychology entails acceptance of two things, modularity (which he describes as distinct parts of the brain which are genetically coded for that do certain things) and the notion that the human psyche popped into existence on the African Serengeti.

Greg’s definition of modularity is slightly problematic and furthermore it seems to be jumping the gun to suggest that it is part of a definition of evolutionary psychology. You can read books such as The Selfish Gene or David Buss’ Evolutionary Psychology that make scant reference to modularity as he describes it.

Frustratingly the sound quality makes him semi-audible at a point where he seems to say the notion of modularity conflicts with the idea that we can learn things. This is pure nonsense - much of what is thought about our capacity to learn is massively in line with the idea of modules (Chomsky and Fodor being extreme examples) - but to be fair he may have qualified this in a bit I can’t make out.

I will talk more about why this panel seem to be giving a misleading picture of mental modularity in the next section.

I know of no evolutionary psychologist who does not allow for the fact that our minds are products of eras of evolution, and that things like emotions and instincts might well have as venerable a history as things like circulatory systems and eyes.

The popular contention that the minds of modern humans are effectively the same as those who lived during the Pleistocene is held according to the available evidence. It would not be fatal to EP as a field to discover that changes in the mind had occurred in the interim.

The way I understand it is to ask myself if modern humans have the same innate psychological capacities as those who lived a hundred years ago. I think so. Five hundred years ago? I think so. When does the evidence begin to mount to suggest that people generally did have different innate psychological capacities?  At some point in the Pleistocene seems to be the general contention, and it’s held tentatively.

He finishes by claiming that Evolutionary Psychology hasn’t moved on in any significant way since Tooby and Cosmides, which I find ignorant. No doubt everyone working in the field owes them a great debt, but they aren’t mired in the territory initially mapped out. My favorite book on the subject is David Buss’ Evolutionary Psychology - a dense 400 page treatise – and it makes scant reference to the stuff Greg claims is definitive and goes beyond what he seems to think the field is limited to.

Are Brains Organised?
At this point Stephanie asks Indre to comment on the notion that brains are organised. Given Greg’s dismissive attitude in regard to modularity it’s nice to see this reaction from Stephanie and a relief to learn that Indre is pretty emphatic about the fact that the brain is organised and that modularity is a fair way to think about the brain at certain levels of abstraction.

However, there is a misleading element here in that Evolutionary Psychology’s primary focus is on behaviour (what the mind does) rather than anatomy (what the brain is). The impact of anatomy on behaviour is obvious, but it is the behaviour itself that is the primary focus.

Indre claims that Evolutionary Psychology “glosses over important details” by only examining things at a certain level, the brain is a system and has to be understood in terms of interlocking subsystems and parts.

So I think the modules she is talking about as a neuroscientist are likely to distinct areas of the brain and how they interact and what they do. Whereas the modularity discussed by evolutionary psychologists is behavioural – the mind does particular processes under certain circumstances and whilst there must be physical things behind the process we don’t necessarily know what bits of the brain are involved - “mental module” is the phrase used to sum that up.

So whilst Indre is right to assert that EP doesn’t say an awful lot about the development and history of physical structures in the brain, she misses that its focus is behaviour. For example when she says:

“So you can look at the brain as these different layers and there are certainly some parts that are more modular than others particularly if you look at the architecture of the brain…”

She is referring to modularity in a different way to how Evolutionary Psychologists look at it. Presumably some mental modules are keyed into particular parts of the brain’s anatomy, but many may use a number of different parts of the brain’s anatomy and any given part of the brain’s anatomy might function in a number of different mental modules.

“So you have to put it back into the context that the brain works as one thing and there are certainly multiple systems involved … if you try to nail down a particular function either at a particular region or a particular level eventually you are going to have a problem because brain doesn’t act in a vacuum and is highly interconnected.”

The context she herself fails to mention is that we aren’t talking of physical regions or levels or anatomy. There is nothing about mental modularity that conflicts with an appreciation that the brain is a complex and interconnected system working on many levels.

As far as I see it mental modules have more in common with things like cognitive shortcuts, schema and heuristics, rather than bits of grey matter.

The Dreaded Media
Stephanie then asks Amanda to comment on how EP tends to be portrayed in the media.

I wonder if she will lay the blame for how EP tends to be portrayed in the media on the media, or on Evolutionary Psychology? Let’s see.

Her opening remark is:

“Well a big problem with evolutionary psychology, particularly in the media, is that humans have a whole social and other kinds of behaviour but they focus on sex and gender (inaudible) that is a little bit offensive. Often Evolutionary Psychology tends to promote and perpetuate these rigid gender roles where women are undersexed, submissive, vain and frivolous and men are aggressive and violent, oversexed and status seeking,”

That's a bit like saying Newton was promoting defenestrations when he came up with all that gravity malarkey.

That the average man in typical circumstances is more aggressive than the average woman is something understood by all psychological perspectives and which has mountains of evidentiary support.

When social psychologists approach this fact with an eye to understanding the impact of culture and society on patterns of violence they very rarely get accused of seeking to promote the status quo.

Yet to look at that same phenomena with an eye to understanding how that pattern might have formed as a consequence of our natural history, and to contrast it to patterns we see elsewhere in nature – that is to promote it?

Why?

“(Evolutionary Psychology) does not claim that human behaviours are inevitable and unchangeable and makes no moral pronouncements” – Evolutionary Psychology: A Graphic Guide.

As to the claim that evolutionary psychologists have studied comparative frivolity, I don’t deny this but I am sceptical – anyone got any links?

She complains about media motives and standards in reporting science – no argument from me, I just think it should be clear that this is a phenomena that has more to do with the attitudes of media producers and consumers than it does with scientists.

Criteria Needed to show Behaviour (??)
Stephanie asks PZ a question – it’s not clearly audible but the gist is that she wants to know what he thinks the criteria should be in order to show a behaviour, presumably within an evolutionary context.

I can only make out every other word – Indre needs to give the others a lesson in audibility I think.

He claims all evolutionary psychologists do is look at the evidence of behaviour and infer what the evolutionary basis of it is.

To what standards is the inference done? He does not indicate.

He claims we don’t know the genes for behaviour. As far as I know most behaviours that have been associated with genes give us the impression that behaviour is largely polygenic. This does not get mentioned. He does not provide a reason why, in the absence of solid information about genetic components, we should not examine other available evidence.

Does he advocate that we teach nothing about the development of life on earth prior to the oldest DNA we can find? We simply can’t assume that ancient taxa have any relevance because we don’t have genes? Abiogenesis is bunk because we don’t have the actual replicating chemicals from that time?

No, obviously knowing what genes contribute which influences to what behaviours would be lovely. I imagine in the future such information will help clarify a lot. We don’t. There’s other evidence to weigh up in the interim.

He returns to Indre’s points about specific bits of the brain doing specific things and mental modules. He says something like “there is not a colouring in between the lines module in the brain, or a module that says do you like broccoli”.

I don’t know of anyone in the field who suggests such things. Jokes are all well and good – but why not tackle one of the actual mental modules that have been proposed and explain why it doesn’t jazz with evolutionary biology?

Moreover he seems to repeat Indre’s mistake in that he entails the mental module stuff with a bit of the brain rather than a cognitive shortcut.

“They assume there is a one-to-one mapping of genes to behaviours.”

No they don’t. They admit that they don’t know much about what genes influence what behaviours (yet) and that in all likelihood innate behavioural tendencies are a polygenic thing.

“If you talk about the evolution of genes you’ve got to start with genes.”

Well, no you don’t and that’s not what they do: they examine evolutionary explanations for behaviour.

Greg takes over – again not easy to hear his bit. I think he says that anthropologists cede that there are systems of behaviour but that the variety of outputs undermines the notion of a universal system. I’m annoyed that I can’t make this out – because it doesn’t seem too misleading.

We obviously know that no two human populations have shared the exact same environment. Given the tremendous number of variables involved in the course of human life, it shouldn’t be a surprise that populations in similar environments nevertheless differ culturally.

That is not a challenge to evolutionary psychology. Generally evolutionary psychology looks at the similarities between human populations (and those of other species too) and gives more weight to behaviours that are common or universal to human populations.

He criticises the Tooby cheater detection module exercise on account of it contrasting an abstract logical problem (cards with a certain letter on one side should have a certain number on the other side) with a more dramatically illustrated one that is pertinent to everyday life (drinkers of a certain age may only order certain drinks).

Tooby claimed that the fact that people are much better at the second task than the first task – despite the logic behind the tasks being the same – was evidence that detecting a cheat within a social situation is encapsulated within a module providing us with a shortcut to the same logical problem that we find relatively difficult in the abstract.

Greg pooh-poohs this by pointing out that people will have had more experience of the sort of social problem illustrated by the example of underage drinkers.

That would be a valid criticism were it not for the fact that he misses that this particular experiment was the start of an investigation and a resulting body of work, and that varying scenarios, including unusual and nonsensical ones, still yield the same sort of pattern of results.

The reason that the comparison between the letters and numbers problem and the underage drinkers gets used in textbooks and introductions is because it is the starkest example of the phenomena.

This does not mean that the whole theory relies on it, there are other experiments that compliment this notion.

So it’s a bit like someone saying “those studies Darwin carried out on fancy pigeons hardly say much about natural history, and therefore evolution is weak sauce”.

Amanda exacerbates the same misunderstanding by saying that the experiment was done with college students and they are obsessed with going into bars (what was that you said earlier about the media and stereotypes Amanda?).

Greg assures her that the subjects were indeed all college students.

They are demonstrably wrong.

This is now a very famous psychology experiment and versions of it have been performed with all sorts of participants, including the Shiwiar, a foraging tribe from Ecuador. The performance of the Shiwiar was 86%, well within the range of 75% to 92% recorded by students at Harvard.

I think Indre then goes on to talk about the plasticity of the brain and changes during development. This is not something that mounts any sort of challenge to EP. In regard to the cheater module – what would it be about the notion that we have tend to have a schema that makes us alert to cheats which would undermine the notion that the brain is a versatile organ that responds in all kinds of ways to various inputs?

PZ then goes on to talk about the tendency of evolutionary psychologists to propose that modern humans are psychologically equivalent to those of 10,000 years ago.

See my earlier to objection to Greg raising this point – though at least PZ cedes that aspects of our psychology may well be older than the Pleistocene.

He says they treat the notions that psychological traits might have developed subsequently as negligible. Yes – but he does not mention that this is a tentative position many hold because of the paucity of contrary evidence.

He claims reading and writing stand as contrary evidence.

They do not. They are not innate. People from cultures with no history of literature can be taught to read and write and people from literate cultures are nevertheless illiterate until taught how to read and write. The contention then is that a human of 10,000 years ago, whilst almost certainly functionally illiterate given their culture, could probably have been taught to read and write.

He claims that ancient humans had “primitive hunter gather brains” according to “their inference not mine” (he means evolutionary psychologists here I presume, though this seems ironic seeing as he actually IS suggesting they had more primitive brains given that they couldn’t read or write).

Anyway he’s wrong. Once again - the tentative contention is that their brains were no more “primitive” than ours. They were - in terms of psychological capacity – equivalent. So they didn’t have reading and writing but they were *probably* ready for such a thing.

He claims that the ability of the brain to adapt is kind of plastic rather than genetic – seems like lunacy to me to suggest that the two things are mutually exclusive.

Natural Selection
Amanda introduces the notion of evolutionary drivers other than natural selection or sexual selection by referring to the Russian Fox experiments.

The notion that evolutionary psychology relies too heavily on natural and sexual selection is oft repeated. As far as I am aware most evolutionary psychologists are cognizant of …

1)      Natural selection.
2)      Sexual selection.
3)      Genetic Drift.
4)      Belyaevian “piggybacking” of an unselected trait on the back of a selected one.
5)      Epigenetics.

… as all playing a role in evolution. So I’m not sure how this is an objection. Given that if certain behaviours evolved then they, you know, evolved. So whichever mechanisms of evolution played a role in the development of the behaviour – it remains a behaviour with an evolutionary legacy.

Natural and sexual selection do tend to get most of the attention and this is because they tend to possess more explanatory power.

PZ says evolutionary psychologists downplay the genetic diversity of the present. It would be interesting to know where they do so and why. Examples seem pretty thin on the ground.

Greg again – can’t hear him well, but he seems to suggest that the understanding of adaptation professed by Evolutionary Psychologists comes from a shonky definition someone gave at a conference somewhere. I very much doubt that.

He talks about some studies done into human preferences for certain landscapes. He seems to be doing the same thing he did in regards to the cheater detection module, in that he is pulling a few examples out and saying how ludicrous they are (so he mentions that the notion that “we like bonsai trees” is pertinent to notions of us preferring savannah landscapes to some hilarity in the course of this section). He does not talk about the wider understanding of this line of enquiry, the extent of variety of the supporting evidence, the number of participants, quality of experiments and so on.

He seems to suggest that Evolutionary Psychologists claim that the Serengeti represents an optimal environment (they don’t, they claim that life in Africa probably left behavioural propensities) and that this is challenged by the fact that the Serengeti is currently inhospitable (not pertinent).

Pleistocene Again
PZ then goes on to complain that Evolutionary Psychologists tend to regard Palaeolithic humans as a monoculture and derive too much from a cartoon image of ancient humans.

No – the opposite is true. Many of them tentatively contend we are of the same innate psychological capacity as people living in the Pleistocene. People today are capable of cultural diversity, so therefore if people in the Pleistocene were psychologically equivalent they would be able to enjoy cultural diversity.

PZ then says that evolutionary psychologists somehow miss the point that the universals they propose adaptations to (predation and so on) have always been true for our ancestors and for other forms of life.

Seems an odd objection – do evolutionary psychologists state that humans are the only species to feel fear of predators, for example? No. It would be totally consistent with evolutionary psychology to assume that our ancestors experienced fear long before they were human.

Indre claims she will be a devil’s advocate and points out that it is during the time period being discussed that the brain assumed its typical shape.

She is right here but she is missing the point that it is more as a result of looking back (gathering evidence as to when certain behaviours can no longer be found in the archaeological record) as opposed to “when did the brain assume it’s current shape” (which is no doubt important, but not the whole story) which leads to the contention.

The panel then seem to derive some amusement from the fact that the Pleistocene is a big long period of history. I wonder why? If it was a great big period, and it only finished 12,000 years ago, it seems to make the proposition that a great deal relating to the innate content of our minds occurred therein all the more modest.

Half an hour in, so I am going to stop there for now.