Lucus a non lucendo

by Daniel on April 7, 2004

In Latin, a lucus is a “dark grove”. In the eighteenth century, British etymologists decided that the word lucus came from the root verb lucere, meaning “to shine”. The idea was that a lucus was called a lucus because there was no lucendo going on there. The fact that this explanation achieved currency among schoolmasters gives you some sort of idea of the desperate state of Classical scholarship in Britain in the eighteenth century[1], by way of an introductory toccata to a short but ill-tempered discussion on another field in which truly terrible explanations are par for the course; Evolutionary Psychology. People who have read Henry’s comments in the same area are excused this one.

The trouble with lucus a non lucendo type explanations is that having learned one of them doesn’t help you at all with deducing any others. For example, if there were a particular type of mushroom that usually grew in dark groves, then the principle which led you to establish lucere as the root of lucus might start you thinking that it should probably be called a cuniculus, since rabbits don’t eat it. Or a vinum, because it doesn’t taste of wine. Or a catapult, because it isn’t one. Because the “non lucendo” explanation didn’t really add anything to our understanding of why a grove is called lucus, it doesn’t help you move on. There’s a general principle at work here, related to the parsimony of hypotheses; if something’s going to count as an explanation of X, then it ought to at least partly work as an explanation of things which are similar to X.

A number of explanations in evolutionary psychology don’t do very well by this criterion. Most glaringly, the famous “Natural History of Rape” by Randy Thornhill and Craig Palmer, which goes on for several hundred pages explaining how rape is either “an adaptation that was directly favored by selection because it increased male reproductive success by way of increasing mate number” or “a product of other psychological adaptations, especially those that function to produce the sexual desires of males for multiple partners without commitment”. This is a pretty controversial theory in and of itself, but let’s pretend that we all took it on board as a really good theory of why men commit rapes. How far does this get us as a theory of things similar to rape?

Well, what’s similar to rape? Two things; consensual sex is similar to rape in that it involves sex. And aggravated sexual battery is similar to rape in that it’s a sexual assault. Thornhill and Palmer’s theory (that rape is either a mating strategy or a byproduct of mating strategies) works reasonably well in giving us a theory of consensual sex – that’s also likely to be a mating strategy. But not very well at all in giving us a theory of aggravated sexual battery. Or indeed of any other sex crime which does not involve the vaginal penetration of a woman of childbearing age. It’s an explanation that doesn’t explain.

And similarly with the Sad Hominid explanation of depression (that under stress, some people become depressed, which helps their reproductive chances because it means that people will feel sorry for them and look after them). Ignoring the physiological implausibility of this explanation (clinical depression is often associated with erectile dysfunction in men, and you’re gonna have to work hard to convince me that impotence is a good way of maximising one’s progeny), it fails by the lucus a non lucendo criterion as well. Some people under stress end up with depression. However other people develop different mental illnesses, most of which render them much less sympathetic than the stereotypical depression patient. It’s hard to see this theory of depression working well as a theory of paranoid behaviour or of schizophrenia. Which is odd, as cases of depression are often found alongside cases of one of these other serious mental disorders.

Part of the issue here is that any form of psychology makes a poor sociology, and it’s only evolutionary psychology that tries to pretend that the distinction between individual and social psychology doesn’t exist.

[The reason for this, by the way, is that “evolutionary psychology” is simply a rebranding exercise for sociobiology. It’s not extending proven psychological results forward into the social sphere. It’s building backward into a “hard” science in order to shore up already constructed sociological theories which have come under attack. As a method of scientific inquiry, this has all the merits of constructing a house roof first and foundations last.]

And the other part of the issue is that, however much Steven Pinker would like it to be, the mind is not a Swiss Army knife and the division of psychological entities into modules is something without anatomical basis when carried out at the level of anything other than the broadest and most general urbehaviours. The only things which are even a candidate for evolutionary explanation are the big drives; eating, reproduction, childcare, status, suppression of samespecies aggression. And these are the things in which nobody has ever disputed the role of evolution. The fact that a) we have a sex drive and b) the existence of this sex drive is explained by our Darwinian imperative toward reproduction was there in Freud for chrissakes. And the fact that the simple existence of a sex drive is next to useless in explaining any specific human sexual behaviour has been known since very shortly after Freud. It’s the same with all our broad drives. Almost everything we do in an average day is just simply too complicated and specific to a particular time and place to be the subject of any evolved module (or to be the subject of any general reasoning at all, as Hayek pointed out).

So when one feels tempted to compromise with the evolutionary psychologists, and to say that “perhaps Darwinian evolutionary theory can shine some light on this social conundrum”, it’s worth remembering that this light is highly likely to be a lucus a non lucendo. Vale.

Footnotes:
[1]An entirely unfair remark on my part; the original source of the “lucus a non lucendo” etymology was Marcus Honoratus[2] in the fourth century AD and the majority of serious British classicists correctly deduced that he was joking. But it was in the C18 that the error became popular.
[2]Or possibly Marcus Terentius Varro in the second century BC. Or possibly Virgil[3].
[3]By the way, I was never taught this crap, I just pick it up off Google.

{ 48 comments }

1

Anno-nymous 04.07.04 at 4:14 pm

I don’t know if Pinker’s changed his tone in the past few years, but I remember that in “How the Mind Works” he freely acknowledged that his speculative ideas about why people like music and all that were, indeed, speculation. Hypotheses, hopefully to be validated at some future date by game theorists and their models.

I can understand the objection that making ex post facto “predictions” is hardly scientific, and that perhaps human behavior is just too complicated for all the questions to be satisfactorily answered. But at least evolutionary psychology’s assumptions are *true*, not just useful for model-building like economics’.

2

Paul Orwin 04.07.04 at 4:18 pm

A major problem in popularization of evolutionary psychology (pop ev psych? blech…) is a really inadequate understanding of evolution and genetics/heredity. It is silly, and unproductive, to approach evolutionary biology as a series of just so stories explaining how trait X developed so species Y could have more progeny. In the aggregate, evolutionary biology predicts that fecundity will drive genetic diversity (i.e. genes that make you reproductively successful will have a higher frequency in a population), but there is no reason that *every * trait locus must affect fecundity. If I have dark hair (and I do) am I more or less successful than a blonde (depends).

The interesting thing here to me, aside from the generally poor state of scientific education, is a sort of catch-22 implicit in the discussion. As a whole, I want people to read popularizations of science, because I hope it will get them interested and involved in one of the great enterprises of our civilization. However, the terrible oversimplifications that are essentially required in all but the best of these books make the whole thing seem counterproductive.

3

dsquared 04.07.04 at 4:32 pm

at least evolutionary psychology’s assumptions are true

No they’re not. The mind isn’t modular, and genetic inheritance doesn’t work in the way in which a lot of “selfish gene” models seem to need it to. The mathematics of gene selection don’t work anything like as well for inheritance of specific traits if you’re dealing in gene-complexes rather than genes, so the discovery that the total number in the human genome was on the low side was more damaging for the ev psych project than any of them admitted.

4

Bill Carone 04.07.04 at 4:54 pm

“Part of the issue here is that any form of psychology makes a poor sociology”

Would you say more about that (or point me to someone who does)? It sounds interesting.

5

JP 04.07.04 at 5:15 pm

“The mathematics of gene selection don’t work anything like as well for inheritance of specific traits if you’re dealing in gene-complexes rather than genes.”

What sort of evolutionary models are you thinking of when making this claim? Could you give some citations?

6

tim 04.07.04 at 5:45 pm

Perhaps the thinking is marred by the whole “survival of the fittest” idea. There was an interesting article a few years back in Phys Rev which noted in passing that the proper model of evolution isn’t best understood as “survival of the fittest” but rather “elimination of the least fit.” While the two ideas sound similar, they lead to different results. The latter, in particular, doesn’t support the “just-so” stories of evolutionary psychology nearly as well.

7

tim 04.07.04 at 5:49 pm

Boettcher and Percus, “Optimization with Extremal Dynamics,” Phys Rev Lett, 86 (2001) 5211

The article isn’t primarily concerned with evolution, is short, and includes references for those of you who are interested.

8

dsquared 04.07.04 at 5:50 pm

I’m thinking of population genetics models which use selection coefficients. If you are working on a one-gene-one-trait model, these selection coefficients have a natural interpretation as the “adaptiveness” of the trait in question. If the model has context-dependence, then this natural interpretation can’t be made and it’s very difficult to say anythign coherent about individual traits.

Basically, the citation is to Sobers & Lewontin “Artifact, Cause and Genic Selection”.

9

Kevin Drum 04.07.04 at 6:14 pm

Um, do you have anyone besides Lewontin to cite? His disdain for sociobiology/ev psych is so well known and so over the top that you really need more than just him to make your case.

By the way, if the only candidates for evolutionary explanation are the “broadest and most general ur-behaviours,” would you say the same is true for physical evolution? If not, why do you think the brain evolved so much differently than all the other organs?

I have heard many good critiques of ev psych, mostly along the lines that although it might be true, it doesn’t provide any testable hypothoses and is therefore useless. You however, seem to go considerably further: ev psych explanations simply aren’t true at all except for the very broadest behaviors. I think you ought to provide a bit more evidence if you plan to make a sweeping statement like this. One off critiques of specific ev psych stories just aren’t enough.

Paul Orwin: what you say is almost certainly true, and it’s unlikely that popular books are going to include serious discussion of gene complexes and population genetics. However, outside of the popular press, it strikes me that most books on the subject treat the subject with a bit more subtlety than you suggest.

The original backlash against sociobiology was largely driven by racial concerns (if it were true, it was feared it could be used to demonstrate innate inferiority of certain races), but these days an awful lot of the backlash seems to be driven more by exasperation over individual stories like the depression one that started this thread. It’s too bad. I suspect that when it matures more ev psych will turn out to be a useful tool, and perhaps all these weird explanations for every possible behavior is just the price we pay along the way. Eventually everyone will get over this phase and make some genuine progress. After all, alchemy eventually gave us chemistry.

10

pw 04.07.04 at 6:16 pm

Someone who really wants to get Popper spinning in his grave should marry ev psych and punctuated equilibrium.

One common chestnut in p.e. is that some genes spread through a population simply because they’re present by chance in an isolated group that happens to end up with some other reproductive advantage, or in the survivors of some (unrelated to that gene) major weeding-out event. Another is that genes that confer fitness during punctuations may spread through a population despite a neutral or even negative effect during normal periods. (On the micro level, the former has been inordinately useful to students of congenital disease, and that latter has been invoked to explain high blood pressure in african-americans and anomalous body mass among pacific islanders.)

If you invoked a few well-placed catastrophes and migrations (some of them even documented) you could use ev psych to explain pretty much anything, no matter how apparently counter to reproductive success under sensible conditions.

11

Anno-nymous 04.07.04 at 6:22 pm

Pinker may like modularity, but I don’t see how that’s relevant to the enterprise of evolutionary psychology in general. And one-gene-one-trait assumptions might make for easier models (adding a level of abstraction, I suppose), but I can’t imagine that would affect results in any but a very small minority of cases.

Genes that tend to enhance their own ability to propagate, propagate. If the mind is affected by genetics, then evolution will sculpt the mind in a manner that maximizes the propagation of the genes so affecting it. And if some behavior is related to the propagation of an individual’s genes, then we can fairly safely expect that evolution will have had an effect on that behavior.

Not all behaviors affect the propagation of genes — there are behavioral equivalents to brown hair versus blond, say. But if a game theorist develops a plausible model that shows that a certain behavior really does affect survival or reproduction or fecundity or whatever, then why not accept that evolution has had a role?

Dsquared — is there anything in your objections specific to evolutionary psychology, or do they apply equally to physical/physiological evolution as well?

12

jp 04.07.04 at 6:27 pm

dsquared,

It seems to me that the kind of broad-based critique of sociobiology that you are attempting requires a stronger result than the interpretational worry of Sober and Lewontin. In fact, I can’t quite see what makes their discussion more than a red herring in this case.

Whether or not any explanations offered by sociobiologists (and here I don’t mean only human sociobiologists – presumably a population-genetic critique would apply equally to animals) are good ones, they do not depend on spelling models out in genic terms, even if this is routinely done. What you would need to demonstrate is that one cannot obtain the results of optimisation models (say, ESS approaches) when you take the details of inheritance into account. However, this is not the case. See, for instance, Eshel, 1996, J. Math. Biol., 34: 485-510; Hammerstein, 1996, J. Math. Biol., 34: 511-532; Eshel, Feldman and Bergman, 1998, J. Theor. Biol. 191: 391-396.

There is a lot of shoddy sociobiology out there, but the core enterprise does not seem to be theoretically unsound. Sticking to empirical objections is therefore more effective.

13

pw 04.07.04 at 6:36 pm

“Not all behaviors affect the propagation of genes — there are behavioral equivalents to brown hair versus blond, say. But if a game theorist develops a plausible model that shows that a certain behavior really does affect survival or reproduction or fecundity or whatever, then why not accept that evolution has had a role?”

Because you still need a gene (or constellation of genes) that will reliably produce that behavior, without producing other, possibly unrelated behavior that could be detrimental to the gene’s survival. The problem is that genotype is not what’s selected on, phenotype is. And the link between the two is complex, fraught and extraordinarily context-dependent (yes, whether you’re talking about physical characteristics or hypothetical psychological ones. So although much of the general theory is reasonable, almost all of the specific stuff built on top of it isn’t really much better than Freud’s fairy tales.

14

chun the unavoidable 04.07.04 at 6:56 pm

Freud was far, far more careful in his claims than the EP folks Daniel discusses here, none of whom are likely, I think it’s safe to say, to be considered one of the major intellectual figures of their era.

15

tim 04.07.04 at 6:57 pm

“genes that tend to enhance their own ability to propagate, propagate.”

And yet the opposite – genes that don’t tend to enhance their own ability to propagate don’t propagate – isn’t true.

16

dsquared 04.07.04 at 7:03 pm

Kevin:

1. I’m not responding to argumentum ad hominem about Lewontin. His paper with Sobers is widely cited in the literature on selection, and not just in the context of sociobiology. Lewontin is a genuine authority in the field. Everyone else is prepared to address his arguments rather than trying to claim he’s “tainted” by having argued against what he considers to be wrong science, so you can bloody well do so too.

2. The brain, like the hand, is a multi-purpose organ. General features of the hand (like having five fingers) are genetically coded, but specific actions of the hand (like twirling a baton) aren’t. There are specific genes which determine whether you’re going to have legs or not, but no specific genes which determine whether you’re going to be able to walk (this is well-established, btw; walking is a learned behaviour and babies who don’t have human adults around to copy, don’t learn).

Brains have many more general functions and fewer specific functions than physical organs, and so more of what we do with them is learned and less is determined by their physical structure. For example, there is a module in the brain which helps babies recognise faces. But it’s not very good. Any pattern of three dots roughly in a triangle will set it off. In order to distinguish faces from triangular dot patterns, babies have to learn.

3. Evolutionary psychology will not turn out to be a useful tool as long as it keeps saying things which are definitely untrue about the anatomy of the brain. Steve Rose has been banging on about this for years, to no obvious effect.

Anno-nymous

1. Unless traits are modular, it is very difficult to see how they can be acted upon through Darwinian selection.

2. Learned behaviours are also relevant to fecundity, and learned behaviours can be inherited through what one might provocatively call “culture” and less provacatively call “childrearing”. This evolution is Lamarckian in its operation.

3. And evolutionary psychology needs the selection to be Darwinian if it is ever to make any interesting predictions. If the dominant force determining human behaviour is the Lamarckian selection of learned behaviours through culture, then the talk of “fecundity” is a red herring; all one is saying is that people try to do things which have had good results in the past.

You need the modularity of traits in order to get the argument through that important human behaviours are the result of “human nature” in the sense of being behavioural traits which have been selected for in the past and which are not subject to any quick method of change.

JP:

1. The sociobiological explanations do depend on some specific features of the models. In particular, they depend on the coding of individual traits being small relative to the whole genotype, so that it is meaningful to talk of selection pressure on individual traits. See my response to Anno-nymous above; the sociobiologists need modular traits for their research programme to be worth pursuing.

Sober & Lewontin’s critique matters because it shows that, in a model which takes account of the realities of inheritance selection coefficients don’t have a causal role. This seriously damages the sociobiologists’ case because they need behavioural traits to be both a) causally active and b) units of selection.

Your own cites seem pretty tangential to me. The fact that optimisation works in poopulation genetics models is hardly surprising. But the point at issue is whether it makes sense to apply these models to behavioural traits as units of selection. It doesn’t.

To make it clearer, we could say that men who wear Old Spice get laid and men who don’t don’t. So wearing Old Spice aftershave is the equilibrium of any model which takes into account both evolution and preference in toiletries. One can agree with this without being committed to any particular view on whether aftershave preference is genetically coded.

17

Paul Orwin 04.07.04 at 8:22 pm

The problem with Kevin’s arguments (to me, that is, not necessarily the ones DD responds to above) is that they require a level of discrimination on the part of the reader that is simply not rational in light of the poor biology/science education that many, if not most, get. One of the founding fathers of sociobiology, EO Wilson, described some of these barriers to knowledge in Consilience (IIRC). Basically, this is similar to whether you like books by Michael Moore, Al Franken, Ruy Texiera on the left, and (insert smart, serious conservative here) or Ann Coulter on the right. A person reasonably well informed will know what to expect from each, and make a judgment accordingly (read Coulter to boil the blood and or laugh, Moore to read cutting, semi-accurate humor from the left, etc.). In sociobiology/human genetics/ev psych, people tend to be unable to make sound decisions on this type of thing, so you get lots of “just so” stories passed off as deep insights, with few people to contradict. Or, even worse, you get the typical dreadful “Talk of the Nation” thing, where the author of said bullshit is interviewed along with some other academic chosen roughly at random, and the “evenhanded” non-informative approach.
As a note on all of this, there is a disturbing (to me) tendency among people of all stripes to apply a political litmus test to evolutionary biologists (in particular) for some reason. Yes, Lewontin and Gould are (were) both marxists, but so what? Are they right or wrong about the science, and if so, why? It is entirely unremarkable that someone brilliant in a particular field of relatively esoteric science might hold, shall we say, eccentric political views. We can rightfully invoke these views when discussing politics (if desired) but it has nothing at all to do with the merits of their ideas in science, IMHO.

18

Kevin Drum 04.07.04 at 8:35 pm

I wasn’t suggesting that Lewontin isn’t a genuine authority, only that he’s one guy and his prejudices are well known. It doesn’t mean he’s wrong, but it does mean a good argument needs more support than just him. An argument that relied solely on, say, Noam Chomsky, would probably meet the same fate.

I also think you’re overstating what the ev psych folks say, although I’ll grant that they often give you plenty of reason to do it. It’s not so much that baton twirling is genetically coded, but that our ability to twirl batons might be the result of some other features that are genetically coded. This seems a reasonable argument. It’s also going to lead to lots of crap getting thrown out, but that’s the way it goes.

I don’t have a problem with arguing against the crap. May the fittest argument win. But I don’t think the entire field is necessarily crap simply because some individual results are wrong.

In any case, I’d also argue that ev psych has had a prophylactic effect. Hopefully there are damn few people anymore who argue that human behavior is largely unrelated to biology. That wasn’t the case 25 years ago.

19

Anno-nymous 04.07.04 at 8:42 pm

I don’t think anyone here is arguing for pure genetic determinism, dsquared. Your example of walking is a good one. We don’t have to say that there is a gene for walking, only that people who learn to walk (presumably) fare better in life than those who don’t. Therefore, we can expect that a gene-complex will develop that leads to the behavior of walking, given the relatively common environment of being raised around others who walk. This should go without saying — after all, most animals which walk really are genetically programmed to do so, and if humans have lost this trait then it’s only because the environment rendered it unnecessary.

I’m perfectly willing to grant that evolution can act on the manner in which an organism learns, rather than directly on the learned behaviors. Obviously this will lead to many behaviors that are only tangentially related to gene propagation. It is the job of the evolutionary psychologists to discover the proper level at which Darwinian evolution has taken place, and surely there will be cases (perhaps including depression) where a certain behavior is an unselected-for emergent property of the rest of the genome/environment.

I don’t see why you think the Old Spice analogy is trivial. In this case, evolution has led to the more general behavior of “do something if you think it’ll get you laid” rather than anything specifically related to aftershave preference, but that’s enough for me and I imagine enough for any ev psychologist.

Actually, this “prediction” that Old Spice will sell well is the opposite of a lucus a non lucendo explanation, since the principle behind it really does help you understand other behaviors.

That was a little bit scattershot, and doesn’t actually reply to the objections you cite against my previous comments. That’s because I don’t understand your point #1 about modularity. I haven’t read Lewontin, which I think was your reference, and honestly don’t know anything about his arguments. I try to comment here if I think I have something worthwhile to say, but I’m not a professional academic (I’m a college student, neither a biology or economics major) and I get that a lot of you just plain know more than I do. Nevertheless, enough people seem to agree with me that I don’t feel completely foolish defending evolutionary psychology’s value as a potentially productive discipline. I do agree that there’s a lot of terrible speculation that passes itself off as real evolutionary psychology, though.

20

Paul Orwin 04.07.04 at 8:46 pm

If you were to have a political argument, using Chomsky as your source, then clearly that would be an issue. In his academic field, if I understand correctly, his ideas are very well respected (although by no means unquestioned), and a respectable argument about the development of language could be made using his work as a main resource. I think the overall question, “is ev psych bunk?” is a bit oversimplified, because naturally there are good practitioners and bad ones (I’m certainly no expert). My personal opinion is that breathless reports of “the gene for brain size” or “the gene for intelligence” are dreadful oversimplifications that are worse than useless (see my now ancient in blog years running argument with “Godless Capitalist” for more on my opinions in that realm!) The reason that these ideas get oversimplified and distorted is because the overall conception of what evolution is (survival of the fittest) fails at a basic level when applied to our lives. This conception itself is a gross oversimplification, leading the useless and counterproductive Darwin wars, arguing over things that not only arent in doubt, but are basically giant strawmen. My totally citationless feeling on the subject is that the most popular ev psych books, i.e. the ones that get the most press, are the bad ones, like the Thornhill book or the Bell Curve. Frankly, a good, honest book detailing the science of human heredity’s role in behavior would sell in the single digits.

21

Andrew Brown 04.07.04 at 8:57 pm

But Lewontin is a superb geneticist and much wiser than his tone of weary omniscience would at second glance suggest. He’s a much more considerable scientist than Steve Gould ever was and his criticisms of the human genome project were absolutely spot on.

With that said, there is a small quantity of evopsych which is of very high quality. Try Robin Dunbar’s stuff, for example. Just because it’s easy to do it badly doesn’t make it impossible to do it well.

22

Mark 04.07.04 at 9:07 pm

It’s easy to find examples of bogus speculation based on evolutionary reasoning; depression and rape being but two. If you look at the local bookstore one could disparage any one of our fields.

The increasing recognition of kin selection, which has been criticized but to my mind not discredited, links evolutionary psychology to sociology. I don’t think we should put our disciplines in pigeon holes. Paradigm shifts often occur when seemingly disparate fields merge.

23

Shai 04.07.04 at 9:48 pm

dsquared says:

“no specific genes which determine whether you’re going to be able to walk (this is well-established, btw; walking is a learned behaviour and babies who don’t have human adults around to copy, don’t learn).”

pinker says:

“The !Kung San of the Kalahari Desert in southern Africa believe that children must be drilled to sit, stand, and walk. They carefully pile sand around their infants to prop them upright, and sure enough, every one of these infants soon sits up on its own. We find this amusing because we have observed the results of the experiment that the San are unwilling to chance: we don’t teach our children to sit, stand, and walk and they do it anyway, on their own schedule.”

I don’t remember the full story myself, but iirc from a reading of the Blank Slate a year ago, he also explains that that kicking in the womb enables the development of the joints in the leg.

24

Bill 04.07.04 at 10:26 pm

“The only things which are even a candidate for evolutionary explanation are the big drives; eating, reproduction, childcare, status, suppression of same-species aggression.” Huh? Why?

Is there something in our evolution which makes it impossible for us to have wired-in behaviors as complex as those of the social insects? Could you mention it?

(Ants, too, for that matter. If, as you say, evolutionary psychology descends from sociobiology, perhaps it’s not entirely a coincidence that it doesn’t descend from people whose evolutionary and neurobiological worldview rests on psychotherapy and pigeon conditioning experiments…)

It doesn’t follow that our brains have as much detail hardwired in as bees do. But it does seem to make it somewhat plausible, and to falsify arguments which are so general that they claim to show that no evolved organism could.

(As a wild guess — not being a psychologist, but a molecular biologist turned computer programmer — it seems plausible that our brains could have about as many bits of preprogramming as bees do. Then since our brains have a whole lot more space for learned stuff, the preprogramming would tend to be less conspicuous. But I doubt that stops rather complex behaviors from being hardwired in. Similar scaling arguments would apply to birds, and I’ve seen some pretty impressive bird nests which I doubt were learned behavior, and I’ve read about planetarium experiments showing that babies of some species of birds are wired to watch the rotation of the stars from the nest at night in order to figure out what’s a reliable guide to north.)

25

Shai 04.07.04 at 10:32 pm

paul orwin says:

“The reason that these ideas get oversimplified and distorted is because the overall conception of what evolution is (survival of the fittest) fails at a basic level when applied to our lives.”

exactly:

“The process of change in the genetic composition of populations caused by differences in survival is what Darwin called natural selection”

and:

“A better way of expressing this idea is ‘survival of the fit enough.’ Portraying nature as ‘red in tooth and claw,’ wherein living things always engage in a life-or-death struggle against competitors grossly oversimplifies what is really going on. Many life forms get by for eons by existing in niches that other organisms are not suited for. For example, brine shrimp live in water that is unsuitable for potential aquatic enemies, and they apparently have no significant competitors for food.”

I think this is more often an error of the general public than the popularizers themselves, however, I suppose they share some of the blame with book titles like “the selfish gene”. By the way, I audited a general biology course. Dawkins wasn’t mentioned once in the evolution and population biology unit.

refs:

evolution.berkeley.edu
encyclopedia of life sciences

26

John Kozak 04.08.04 at 12:01 am

regarding “lucus”, I think the etymological intuition, if the not the analysis, was correct – “lucus” was originally a clearing in a forest with ritual uses; the sense then transferred to a ritual woody site.

27

Jonathan Goodwin 04.08.04 at 12:14 am

The original epigram is from Quintillian.

28

Jeremy Osner 04.08.04 at 2:14 am

Shai — the fact that we, unlike the !Kung, do not consciously instruct our infants in the arts of sitting and standing, but allow them to acquire the knack of it on their own, does not mean they are not “learning” it. [I have no clue as to the truth of that anecdote about the !Kung but am taking it on your word, that it's true.] Behavior can be “learned” by observing it in one’s elders or peers without any direct tutelage. Indeed most behavior is — hence the adage “Do as I say, not as I do”, a vain effort to prevent undesirable behaviors from being learned through imitation.

29

Ben Benny 04.08.04 at 2:49 am

dsquared: walking is a learned behaviour and babies who don’t have human adults around to copy, don’t learn).

How in hell are the blind ones doing it then? As I understood until now, learning to walk is instinctive, and occurs at roughly the same rate in all children, even those with mental handicaps. I admit that I have seen only second hand sources on this one, rather than actual studies on walking and early childhood development, but I’d thought it was undisputed.

30

plover 04.08.04 at 4:25 am

My impression (gleaned, I think, largely from Lewontin) is that the types of explanations offered in EP often fall quite easily to arguments from developmental biology (DB). If I’m remembering correctly, Lewontin condemns casual use of “gene for [some trait]” language without knowledge of the developmental processes that produce said trait. From the DB perspective, there is always a question of the effects of the environment on the expression of any given trait, and these effects can derive not just from the inputs to a developing organism (levels of nutrients, etc.) but also to the simple thermodynamic “noisiness” of the physiochemical surroundings. The argument against many EP theories is then that, if given quantitative expression (when this is even possible), they are too mechanistic to fit the (empirically well confirmed) framework that describes a developing organism. I recommend Lewontin’s _The Triple Helix_ which lays out the specifics behind what I’ve been trying to say, and which is pretty much polemic-free.

I don’t think I’ve ever come across a response by EP folks to these criticisms. Has anyone seen one?

paul orwin:
Gould states explictly that, while he was raised by Marxist parents, he himself was not Marxist. Is there some reason not to take him at his word on this? (Lewontin, of course, is a different matter.)

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alf 04.08.04 at 5:02 am

There is a difference between “Evolutionary Psychology” and science which happens to use both evolutionary and psychological ideas. The later is well worth pursuing and has had many good results such as the discovery of the FOXP2 “language” gene. To my knowledge, this was not done by anyone who considers themselves “Evolutionary Psychologists.” This work is done in fields like genetics, physical anthropology and ethology. The claims about specific behaviors that are testable (e.g. “this gene affects language processing in this way” or “human and chimpanzee behavior differs in this specific way”)

People who are capitol E “Evolutionary Psychologists” haven’t made any useful findings to my knowledge (If I’m wrong I’d be glad to know). They generally make broad statements about very complex human behaviors that are not testable at all (e.g. the already mentioned depression and rape claims).

I think there is a lot of confusion between people in this thread because half of the people are saying the first type of “evolutionary psychology” is worthwhile to study, while the second half is saying that “Evolutionary Psychology is a bunch of crap, when both sides are really right.

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dsquared 04.08.04 at 8:24 am

On blind children learning to walk, my reference is a book I picked up about a month ago called “How Babies Learn” or something – don’t have it to hand. Basically, you have to look after a blind baby and encourage it; unsurprisingly nobody’s really gone through the experiment of abandoning blind babies and seeing if they learn to walk unassisted (actually people have, and the evidence from Thai orphanages is that they don’t). Children with mental handicaps do tend to learn to walk more slowly; Down’s syndrome children walk about a year later than non-Down’s.

Anno-nymous: Thanks very much, and I’m using the italicised quotation format below for clairty rather than to be combative.

We don’t have to say that there is a gene for walking, only that people who learn to walk (presumably) fare better in life than those who don’t. Therefore, we can expect that a gene-complex will develop that leads to the behavior of walking, given the relatively common environment of being raised around others who walk.

Yes. But this gene-complex is just “having legs and a brain”.

This should go without saying — after all, most animals which walk really are genetically programmed to do so, and if humans have lost this trait then it’s only because the environment rendered it unnecessary.

Human beings do walk instinctively; they (apparently) scamper, bent over and with their knuckles hanging down. They just don’t walk in the normal way you see people walking by instinct.

I would agree that the Old Spice case is not a lucendo in the particular constructed example, but in any real world case it would be. This is my whole problem with evolutionary psychology; the principle “People do things that will help them get laid” doesn’t actually help you pick out any specific behaviours. If it did, we’d all get laid a lot more.

Kevin: Most of your comments seem like pious hopes for a better evolutionary psychology (plus you’re digging yourself in deeper on the silly ad hominem argument about Lewontin). There will be no such thing. Evolutionary psychology is not a good faith research program; as Paul Orwin points out, the only real advances in this field have been made by serious researchers working outside the “EP” community. It’s a pedigree-creating exercise for sociobiology, which is in turn a cargo-cult sociology.

And your statement that:

Hopefully there are damn few people anymore who argue that human behavior is largely unrelated to biology. That wasn’t the case 25 years ago.

is just weird as a summary of the behavioral sciences in 1980. Nobody since Freud has argued that human behaviour is “unrelated to biology”, or at least nobody who is not a fictional construct. Lots of people have argued that biological imperatives provide few useful explanations of specific human behaviours, and they’ve argued this because they’re right.

Bill: There’s certainly room in our brains for a lot of “wired-in” behaviours, but as a matter of fact we don’t have all that many (or at least, not compared to the number of learned behaviours we have). The majority of our behaviours are learned rather than wired-in, so analysis of behaviour is more likely to be productive if it looks at how that behaviour might be learned than if it tries to tell adaptationist stories about how it might have come to be wired in.

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Shai 04.08.04 at 12:57 pm

jeremy – yes, that is painfully obvious, but I see why I could have been misinterpreted. anyway, Early Development and Attainment of Normal Mature Gait

and for dsquared from elsewhere:

“A visually impaired infant will often be delayed in walking, as he may feel insecure in the upright position. Very little of his body is supported once he is up on his feet, and he may prefer being on the floor until closer to 18 months of age (Fraiberg,1971). Once he does show some interest in walking, he will need to be encouraged to move toward musical or noisy objects, or a familiar voice that is slightly out of his reach. It is also normal for the visually impaired infant to keep his feet further apart for a longer time, as he is understandably more unsure of himself without the visual input, and this will allow him to feel more balanced and secure during the first few months of walking”

“Children with Down syndrome (also called Down’s syndrome) find walking more difficult because they tend to have decreased muscle tone and strength, more flexible joints, and shorter arms and legs than other children.” (in addition to retardation)

But I don’t see why either of those points is relevant unless you think that evolutionary psychologists such as pinker believe that developmental programs don’t require input and output feedback.

“The majority of our behaviours are learned rather than wired-in”

natural selection doesn’t require simple fixed action patterns and learning requires a complex highly organized functional system.

i think you have a decent argument about the methodology and standards of evidence of some practitioners of evolutionary psychology, but the above has nothing to do with it.

“Almost everything we do in an average day is just simply too complicated and specific to a particular time and place to be the subject of any evolved module”

yes, the list here certainly does read like he is proposing a module for picking your nose, or cleaning dirty shorts at noon while singing duran duran, etc.

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dsquared 04.08.04 at 1:26 pm

Shai: There are a number of items on that list which are regarded by developmental psychologists as simply false. Basically everything on the “innate abilities” list is more or less settled to be learned behaviour. (interesting link.

Of the “Innate Social Behaviours”, many of them are developmental stages identified by Piaget. Note also that whoever wrote the list couldn’t resist sneaking “Variation in intelligence (leading to inequalities)” onto it; the conflation of extremely arguable biology with extremely unlikely economic theory is classic Pinker.

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Mike Huben 04.08.04 at 1:35 pm

Lewontin is right about EP misrepresentations of genetic cause the same way he’d be right criticizing “scientific” misrepresentations of mutation from comic books.

I haven’t read “Triple Helix”, but it sounds to me as if Lumsden and Wilson covered much the same ground for sociobiology in “Genes, Mind, and Culture” in 1981.

I disagree with dsquared’s claim that the mind isn’t modular: there’s plenty of evidence of modules from physical organization of the brain and from genetic deficets.

Dsquared also misrepresents genes for walking as ““having legs and a brain” because untrained humans scamper. However, no other apes can really be trained to walk as their “natural” posture: their backs and pelvises are not adapted for it. Nor can they be trained to speak (they don’t have proper equipment) nor can they be trained in full human grammar for signing (and I believe I have read of humans with genetic grammar deficets) and I doubt they can be trained to recognize one of the normal sets of human phonemes.

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Mike Huben 04.08.04 at 1:50 pm

Developmental biology also supports plenty of examples where neural plasticity does NOT work: for example, language aquisition (especially phoneme recognition, where you have a brief window of opportunity to train.)

The example of “adapting” visual cortex to braille recognition is interesting, but I wonder if the possibility of normal (perhaps minor) use of tactile recognition is also handled at least in part by the visual cortex. If so, then the plasticity is not as dramatic, not a “water into wine” conversion.

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dsquared 04.08.04 at 3:48 pm

Mike, you’re presenting a quite controversial area here (language acquisition) as if it were settled science. By no means everyone agrees that phoneme recognition can’t be retrained.

And the evidence for modularity from spatial organisation of the brain only exists for very general ur-behaviours if it exists at all (much more general modules, for example, than anything on Pinker’s list linked above). Everything we know from head trauma cases suggests that the most extraordinary things can be relearnt even after massive damage to the physical substrate.

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john c. halasz 04.08.04 at 6:38 pm

“Nobody since Freud has argued that human behavior is ‘unrelated to biology’ or at least nobody who is not a fictional construct”- such as Sartre or Lacan?

Well, I’m not near as learned as many here, but I’ll offer my $.02 worth. I seems to me that genetically retained behavioral selection applies primarily to instincts. Instincts are neural programs that set off a fixed chain of behaviors given the relevant trigger stimulus. If I recall rightly from ancient reading of Konrad Lorenz, he said that, as neural complexity increases, fixed chains tend to break down and their component behaviors tend to gain an independent drive toward expression. The exampled he cited was house cats. Now it seems to me that as neural complexity increases, animals would tend to acquire an increasing capacity for behavioral learning relatively unchained from fixed instincts based on the implicit grasp of behavioral rules rather than causally fixed processes. But then would not this capacity tend to co-evolve with instinctual endowments, such that those instinctual endowments become inter-nested with requirements for rule-governed behavioral learning, such that the operations of instincts come to depend upon such learning? My speculation would not be at all clear as to the specific selection pressures that would trigger such a line of development, but its specific adaptive advantages would seem obvious.

As for the evolution of “mind”, by which we actually mean the evolution of the brain as an organ with complex interactions between physiological and mental functionnings, it would seem to me that the role of specific, genetically fixed selections would tend to decrease with increases in size/capacity; in other words, that a nonspecific increase in superfluous neural capacity would effectively find its “uses” without being pre-programmed. With respect to human evolution, the growth in brain size is a contingent outcome of bipedalism, which apparently is now being pushed back to 3 to 4 million years ago. The resulting narrowing of the birth canal required neotenic or premature birth to allow the infant’s head to get through without being crushed, which means that embryological rates of growth continue for some time after birth. This, in turn, allowed for further neotenic mutations to extend the term of such embryological growth, leading to increased brain size. Presumably, the increased dependency of the infant and thus the increased dependency of nursing and tending mothers created selection pressures for a further intensification of sociality. (The peculiar evolution of human sexuality, with its year-round estrus, may have evolved so as to increase attachment to the dependent mother-infant dual unit, resulting in the paradoxical configuration that human beings are at once excessively horny and excessively prone to attachment.)

Have y’all heard of the woman who teaches parrots to talk? No, not imitate sounds, but use such sounds contextually and indicatively, very much as efforts to teach great apes sign language have yielded some significant results. The woman’s legit, a professor of psychology I think in the U.of Cal. system, and she’s been at it for about 30 years, with a few generations of parrots. Now parrots are birds and they don’t call ‘em “bird-brains” for nothing, though parrots as a genus have the largest relative brain sizes among birds. But still, they lack mammalian brain structures. I would think such results suggest something of the “plasticity” of neural matter. And as for phonemic pattern recognition capacities, there is a case at the Yerkes Lab of a bonobo, who was raised while its mother was undergoing language training experiments, who shows considerable evidence of such speech recognition.

Surely it is way too Aristotelian of me to think this, but, if the terms of supposed explanations of human behavior do not accord with anything that we experience of the complexion of human behavior, I would think that prima facie grounds for finding them dubious.

Perhaps rather than ev psych, relying on speculative hypotheses about what happened way long ago, there should develop a scientific research program for human ethology, taking human behavior as it actually is and considering it in terms of the interpenetration of neuro-biology and culture.

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dsquared 04.08.04 at 8:41 pm

Not sure about Sartre, but I’m fairly sure I remember Lacan making several references to biology in the short anthologised extract I read. Something about the sexual development of pigeons. I remember it because I remember thinking that it sounded like crap, but there you go.

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john c. halasz 04.08.04 at 9:08 pm

That part needed irony tags.

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Pete 04.08.04 at 11:08 pm

To say, for example, that female preference for a wealthy mate is an adaptation implies that:

1. Female preference for a wealthy mate is genetically encoded, i.e., implemented in the realm of nucleic acids and proteins.

2. There are at least two alleles for “female mate wealth preference”, corresponding to more and less (or presence and absence) of this trait.

Since no one in the world today has the faintest idea of: a. how preference for a wealthy mate could be genetically encoded; b. how any behavior is genetically encoded; c. what different alleles for these genes would look like; d. how greatly the various alleles would differ in fitness–since, in other words, evolutionary psychology operates in a sphere completely untroubled by the constraints of actual mechanism, I find it hard to see it as anything more than “infotainment.” The more we learn about developmental biology, the more we realize that the path from genotype to phenotype can be fiendishly devious. The air of certainty with which many EP proponents give their vaporings is ludicrous.

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Warren 04.09.04 at 4:49 am

At least some of the ideas behind EP are true: The evolution of thinking and language helped survivability and were preserved traits. Likewise with sexuality, the emotional trait of getting angry when hurt and the very existance of memory and short-term memory. A whole bunch of very fundamental things. Probably including an inherited hatred of the smell of feces.

So it makes sense to see how far these ideas can be pushed, how much can be proved somehow.

In practical terms, evolutionary psychology will become less important as neurological knowledge increases.

Traits that expensive will not be preserved unless they confer some reproductive advantage. The ability of African blood cells to repel malaria by forming a sickle shape comes to mind as a biological example. Having legs is another.

So expensive behaviors that are preserved across cultures and time are good candidates for having a genetic origin. Possible candidates include pair-bonding, our protective attitude toward babies, being attracted to fertile, healthy potential mates, particular facial expressions, an attraction to living near bodies of water, hatred of insects, fear of heights, fear of death. You can make your own list.

Genetic inheritence will be less useful in explaining behaviors with (apparent) negative reproductive/survival value, such as suicide, homosexuality, neuroses and psychoses. So it makes sense to look for alternative materialist explanation for these behaviors. Many have been offered, none have been proved.

These behaviors with (apparently) negative survival value may be the result of imperfections inherent in the genetic system. Mutations, transcription errors and so forth might be involved. Alternatively, one might look for a reproductive/survival value for these apparently negative behaviors. It’s at least an intelligent question, as these behaviors are expensive and preserved across time and culture.

Proving things is much harder, of course.

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Warren 04.09.04 at 5:24 am

At least some of the ideas behind EP are true: The evolution of thinking and language helped survivability and were preserved traits. Likewise with sexuality, the emotional trait of getting angry when hurt and the very existance of memory and short-term memory. A whole bunch of very fundamental things. Probably including negative reactions to bitter tastes and certain smells.

So it makes sense to see how far these ideas can be pushed, how much can be proved somehow.

Traits that are expensive will not be preserved unless they confer some reproductive advantage. The ability of African blood cells to repel malaria by forming a sickle shape comes to mind as a biological example. Having legs is another.

So expensive behaviors that are preserved across cultures and time are good candidates for having a genetic origin. Possible candidates include pair-bonding, our protective attitude toward babies, being attracted to fertile, healthy potential mates, particular facial expressions, an attraction to living near bodies of water, hatred of insects, fear of heights, fear of death. You can make your own list.

Genetic inheritence should be less useful in explaining behaviors with (apparent) negative reproductive/survival value, such as suicide, homosexuality, neuroses and psychoses. So it makes sense to look for alternative materialist explanations for these behaviors.

These behaviors with (apparently) negative survival value may be the result of imperfections inherent in the genetic system. Mutations, transcription errors and so forth might be involved. Alternatively, one might look for a reproductive/survival value for these apparently negative behaviors. It’s at least an intelligent question, as these behaviors are expensive and preserved across time and culture.

Evolutionary Psychology is a legitimate area of research, and if it is very hard to to verify hypotheses with experiment or scientific measurement, then it might help to throw around the ideas a whole lot until somebody comes up with ways of verifying or disproving the validity of individual ideas. This is should be worthwhile because we know that at least some neurological, and hence behavioral patterns, are genetically encoded.

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David B 04.09.04 at 12:35 pm

Pots, kettles, glass houses…

Sure, some evo-psych (possibly the majority) is bad science.

But anyone who casts stones at evo-psych (on grounds of scientific methodology) while admiring (take your pick) Freud, Structuralist anthropology, Marxist sociology (or for that matter most other sociology), simply has no shame.

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Bill 04.10.04 at 2:24 am

pete writes

“Since no one in the world today has the faintest idea of: a. how preference for a wealthy mate could be genetically encoded; b. how any behavior is genetically encoded; c. what different alleles for these genes would look like; d. how greatly the various alleles would differ in fitness?since, in other words, evolutionary psychology operates in a sphere completely untroubled by the constraints of actual mechanism, I find it hard to see it as anything more than ‘infotainment.’ The more we learn about developmental biology, the more we realize that the path from genotype to phenotype can be fiendishly devious. The air of certainty with which many EP proponents give their vaporings is ludicrous.”

No one has any better idea how bees are born wired to navigate as they do, yet much is known with certainty about the ways in which they are. Arguments against complicated behavior wired into humans which are so general that they don’t distinguish between humans and bees, proudly declaimed without mentioning counterexamples like bees where pretty clearly the arguments must be invalid somehow, seem pretty ludicrous to me.

Also, when would you say we reached a useful understanding of the mechanism of evolution of non-mental, non-psychological, ordinary biological things like stomachs and blood cells and seeds and disease resistance? Watson and Crick? The slightly earlier experimenters who showed that inheritance followed nucleic acids, not proteins?

Would you say that any confident conclusion made between around 1880 and 1940 regarding the evolution of ordinary non-psychological traits was necessarily ludicrous? How do you feel about the US political battles in against teaching of evolution in that period? Do you believe that the study of the evolution of the nervous system should be held to a completely different standard than the study of the evolution of more mechanically or chemically obvious traits? Why?

None of this is to be taken as blanket defense of everyone who puts pen to paper to make claims about evolution of psychological traits. Even very smart and knowledgeable people sometimes end up with stupid ideas. But that was true of early evolutionists studying and popularizing the evolution of grosser traits as well. While in hindsight (or even, sometimes, in the considered judgment of their contemporaries) they obviously went astray in various ways, still the better ones look like they were much closer to the truth than any of those of their critics who used emotionally charged and less than rigorous arguments to condemn the whole enterprise as ludicrous.

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Steve Reuland 04.11.04 at 6:26 am

“To say, for example, that female preference for a wealthy mate is an adaptation implies that:

1. Female preference for a wealthy mate is genetically encoded, i.e., implemented in the realm of nucleic acids and proteins.”

Not exactly. First of all, the selectable trait doesn’t need to be quite that specific. It’s far more likely that a more generalized behavioral tendancy — like “be attracted to high-status males” — is what’s adaptive. And it will continue to be adaptive insofar as wealth is correlated with high status.

Secondly, there is no need for the specific trait to be encoded in a specific set of genes. Any combination of genes and environment that leads to the behavioral tendancy is enough to make it selectable. All that matters is that it is heritable in some fashion, no matter how indirect.

“2. There are at least two alleles for “female mate wealth preference”, corresponding to more and less (or presence and absence) of this trait.”

I have no idea where this comes from. It makes no difference if the genetic influence is due to a single allele, multiple alleles, a single locus, multiple loci, regulatory elements, or any combination thereof. Perhaps you mean that there must be some variation within the population in order to be selectable. That’s true (or at least it would have to have been true in the past), but that’s a far cry from requiring the trait to be monogenic and diallelic.

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Steve Reuland 04.11.04 at 7:00 am

On a more general note, while I’m the first to agree that there are a number of problems with Ev Psy, I don’t think the case is helped much by flogging strawmen.

First and foremost is the false dichotomy of “nature vs. nurture”. This is something that both sides are guilty of, and there’s a fair amount of it present on this thread. Organisms exist as a complex interplay between their genes and their environment, and there is no meaningful way to fully separate the two. The way in which either acts as an influence is itself heavily influenced by the other. The simple fact is that there is no human trait that is not influenced in some degree by the environment. Likewise, there is also no human trait that cannot be traced back to the influence of genes. But neither one, in isolation, can fully explain any trait. The problem comes when people on either side of the fence think that they can disprove or downplay the influence of one by pointing to evidence for the influence of the other. And because that’s trivial, it’s easy for detractors of Ev Psy to believe that genes are irrelevant, or for proponents to think that genes are everything.

As far as Ev Psy is concerned, what matters it that there exists, at some level, genetic variation that is correlated to behavioral tendancies. I think that’s a fairly noncontroversial proposition in general, though in some (many?) specific cases it’s probably arguable. Note that it doesn’t matter if the effects of the genotype are highly indirect or mediated through environmental cues. So again, pointing out that a given trait will fail to develop in the absence of the proper environmental stimuli is irrelevant. Said trait would probably also fail to develop in the absence of oxygen, but we wouldn’t argue that this indicates that the trait is not genetically influenced, and thus invisible to selection.

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Steve Reuland 04.11.04 at 7:26 am

Daniel writes:

And the fact that the simple existence of a sex drive is next to useless in explaining any specific human sexual behaviour has been known since very shortly after Freud. It’s the same with all our broad drives.

I would say that Ev Psy explains a lot more than the simple existence of a sex drive. It explains, for example, why men tend to be attracted to younger women but women tend to be attracted to older men. It explains why men moreso than women tend to be concerned with phyical attractiveness in a potential mate. It explains why there is a strong taboo against incest in basically every culture you come across. It explains why polygyny is much more common than polyandry (which is next to nonexistent). And so on.

I think it explains quite a bit, just so long as we realize that it explains tendencies and not specifics. And that the thing about tendencies is that they’re statistical, and that one can always find some exceptions.

One place where self-styled evolutionary psychologists really get themselves into trouble is in trying to explain abnormal psychology. The truly horrid “sad hominid” explanation given by Daniel above is one such example. I think people fall into this trap because they’re used to thinking in terms of adaptiveness, and so they come up with adaptive explanations for things which clearly are nonadaptive. It’s much better to view abnormal psychology as, well, abnormal, and to realize that the human mind is far from perfect, so that enough negative stimuli can throw it pretty far off kilter.

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