Larry Moran put up this video of Elisabeth Lloyd discussing the problem of assuming adaptation in evolutionary studies. I think it’s excellent and makes points I wish more people would consider…but strangely, most of the comments over there are expressing extreme distaste while failing to mention any specifics about what they dislike.
Maybe some of you can watch it and explain lucidly what you object to…or what you don’t find objectionable. I get the impression that a lot of people rather rabidly turn their brains off at the merest mention of the word “spandrel”.
In case you didn’t watch it, here’s the main point.
She’s criticizing methodological adaptationists. This is a style of thinking that assumes that only adaptation and selection are important or interesting, and as a philosopher she objects to the replacement of a reasonable null hypothesis (that is, that no selective evolution is occurring for a trait) with the pretense that selections is the null hypothesis…and that if analysis of a trait reveals an absence of evidence for selection, then they will move on to consider other hypotheses.
But they don’t. As she demonstrates with the example of the evolution of the female orgasm, several prominent evolutionary biologists are so fixated on selection that they just make endless chains of adaptive hypotheses, and don’t even consider other explanations (such as drift, genetic hitchhiking, architectural constraints, or developmental mechanisms) as legitimate answers to the question of evolutionary function. It’s a new kind of teleology — they are reluctant to consider that some features of our history were completely purposeless.
Hey, give me time to look it up in the dictionary first, will you!
Maybe they see themselves as some kind or arch enemy of the points you wish people would consider
I’ll get me coat
Not sure how many dictionaries cover this use of the word ‘spandrel’.
Try Wikipedia’s Spandrel (biology) to gain some insight into what has been a contentious issue for some ever since Gould and Lewontin gave their paper in 1979.
Lloyd’s discussion was straightforward and non-technical. Even a non-scientifically trained person like me could follow it. She shows, using the case of female orgasm, that Gould & Lewontin’s spandrel argument should not be dismissed out of hand.
Lloyd’s argument strikes me as being connected to the excesses of evolutionary psychology. She argues that not every evolutionary development has to have an adaptive advantage. The worst evolutionary psychologists make up stories trying to force adaptation into behavior but, as the old saying goes, sometimes shit just happens.
Evolution doesn’t seek goals. It doesn’t seek anything. If a genetic change happens which isn’t harmful, then there’s no evolutionary pressure to get rid of it. It doesn’t have to have a “purpose” and it’s a mistake for biologists to assume every change has to be adaptive.
I will now wait for real biologists to show how and why my amateur explanation is not only a misunderstanding of Lloyd’s argument but silly.
I see the problem: She’s using data.
EP is supposed to be done with the gut.
Great discussion. It seems both postmodernists (“culture mad me do it”) and adaptationists (“genes made me do it”) often seem to bias towards their particular field.
I saw this exact problem recently with Matt Ridley’s WSJ/blog article proposing that sexual selection created both civilization and dislike for income inequality. (Same article, different title questions.) No justification at all for going straight to adaptation for which there are much better explanations anyway.
OK, I get that evolution doesn’t have a goal. (I kind of already knew that…probably from reading either Pharyngula or one of Dawkins’ books.) But since I’m not a scientist myself, I can’t have a reasonable opinion about scientific methodology.
But I can be concerned about my fellow H. sapiens; and I think I heard in the talk that a significant number of women never have orgasms at all. That’s really sad. What can I do to help?
I suspect that those same people who took issue with Lloyd’s talk would have no problem accepting exactly the same explanation for male nipples.
I didn’t have time to watch the full video so far, but I think I understand enough now to proclaim:
Giliell’s adapatatatative theory of female orgasm
Premise A: Orgasms are fun, they’re relaxing, they increas happieness
Premise B: People who have fun, are relaxed and happy are less likely to go on a killing spree.
Conclusion: Women who have orgasms are less likely to murder their family and therefore have a reproductive advantage
Where do I collect my Nobel prize?
Sili
Preferably by haruspices reading in the entrails of the evolutionary psychologists from the other threads.
Makes perfect sense to me. At least as prize-worthy as any of the other theories under consideration.
One eukaryotic cell finds sex boring and refuses to do it with its partner. The other pair finds sex to be a hoot and can’t get anough of it. Now I wonder which of these partners have increased fitness? Which of these could possibly be my common ancestor?
You’re mostly right, except for the part about genetic changes sticking around so long as they’re “not harmful”. If a genetic mutation has no effect on survival, it can only become fixed in the population through drift. This happens all the time, but it’s probably not what is going on with the female orgasm. It’s more likely that the female orgasm persists in the population because, though it has no adaptive function of its own, it is genetically linked to another trait that does have adaptive function. In this case, that would be the male orgasm, which is necessary for ejaculation.
Somebody else mentioned male nipples, and they make for a good analogy. Male nipples are almost certainly not an adaptation, but men have them because they are genetically linked to female nipples, which have the obvious adaptive function of lactation. So male nipples are a byproduct of female nipples. Lisa is saying that the female orgasm might be something similar.
As for PZ wondering why people offer knee-jerk rejections of Lisa’s views, it seems to me that they usually stem from one of two basic misunderstandings: Either they think that natural selection should explain everything in biology, or they think that calling the female orgasm a byproduct devalues it. She’s kinda found herself in the awkward position of having 1) fellow evolutionists accuse her of attacking natural selection (she’s not–the byproduct hypothesis actually relies directly on natural selection being true) and 2) fellow feminists accuse her of de-valuing female sexuality (she’s not–natural selection is not a value system). Every objection that I’ve seen so far has fallen into one of the other of these two camps; either they presuppose adaptation or they mistake an “is” for an “ought”.
What is postmodernism? Anything, everything, anything you want it to mean.
Culture made SGBM say that.
Being relaxed and happy is also good for your health – another reproductive advantage. I think your idea is different from any of the adaptationist hypotheses mentioned in the video because it focuses on women’s capability for orgasms of any kind, rather than just those resulting from intercourse. It would be interesting to see if the same kind of flat distribution of the trait, and absence of correlations with fecundity etc., found for orgasm-with-intercourse data would hold if data on “overall orgasmicity”(supposing someone can come up with a reasonable definition) were used?
Thanks PZ, I hadn’t come across Elisabeth Lloyd, but I’ll be looking out more of her work. The video is an excellent rebuttal to those who dismiss philosophy as useless.
Quoth Wes:
It’s more likely that the female orgasm persists in the population because, though *it has no adaptive function of its own* . . . .
A breathtaking assumption to state as a premise. It may well be that male and female orgasmic mechanisms are inextricably interlinked, but interlinked developments are not automatically non-adaptive.
The criticisms of her talk do appear to be little more than pedantry. They mainly seem to find the talk every “faucet”(sic) of it to be beneath their academic expectations without giving a substantive reason why. Briefly, a spandrel appears to be a structure in architecture that is the byproduct of two arches. She provided a picture of an ornately decorated spandrel as an example. She relates this to an explanation of the female clitoris as it being a byproduct of the development of the penis in males.
Other explanations of the female orgasm kind of retrofit it to some sort of evolutionary purpose like the “Up suck” hypothesis she points out. Humans are wired to be pattern seekers, and they often mistakenly see purpose in patterns where their is none. Like crystal formation it just happens that the atoms of certain crystals arrange that way.
I think she may be saying that biologists may be predisposed to look for a purposeful explanation like natural selection and adaptive adaptation as opposed to more parsimonious explanations like developmental and byproduct explanations that fit the data more accurately.
It reminds me of some of the hypotheses for homosexuality. Like the gay uncle hypothesis that puts some sort of reproductive advantage to homosexuality and thus selection pressure. The actual biological explanation may be a byproduct of hormones that trigger the development of a male fetus. The explanation is entirely biological, but a methodological adaptationist is predisposed to explain it with reproductive success. Those are my thoughts on your question. I don’t think alternate explanations should be treated with automatic disdain because they challenge a ruling paradigm. I would be curious to see a substantive criticism of her thesis.
Argh! Edit: not “their” but “there”
I’d call that a (preliminary) conclusion, since there doesn’t seem to be evidence that it has an adaptive function.
Maybe. If so, then how’s it adaptive and what’s the evidence for that?
Rebecca Watson is culture. She is every culture.
Who knows what culture lurks in the hearts of men? Rebecca Watson knows!
Well, we know some species, like cats, have “trigger conditions” actually becoming pregnant, even while in heat, so.. its not like you couldn’t have had some ancestor ***way*** back, who had a similar adaptation, and then, later, as this became less necessary, i.e., some started getting pregnant without it, you get two “extreme” directions that the original mechanism can go in – ‘not working much at all’ and ‘what it ended up becoming in primates’.
Seems to me, this becomes both “adaptation”, and, “accident”, then. But, yeah, lot of problems with working out what stuff may be incidental (or even if the word means anything in this context, even if we can’t work out the real reason for the changes not just persisting, but actually producing something that doesn’t seem to be ‘necessary’). After all, the argument that its “incidental” begs the question: Then how do you get it at all, if the mechanisms for it never *did* anything in between? Its just.. all the guesses are just a lot of hand waving, without any way to predict result/test them.
As I once said when a friend asked why Giant Pandas have that distinctive black and white pattern in their fur. I answered “Because they do.” Pandas don’t really need to hide from anything, they don’t really need to sneak up on anything, and they don’t appear to use fur patterns as sexual signals, so the answer is just genetic drift. A population of bears with white and black fur was reproductively isolated, and after a while, they all had the same patterns.
It’s not an assumption, and it’s not stated as a premise.
It’s the conclusion Lisa reaches in her research. She argues that the various attempts scientists have made to prove it has some adaptive function have fallen short, and that the hypothesis that best fits what data is available (which admittedly is somewhat spotty) is the byproduct data.
Kagehi,
Did you actually watch the video? Because you’re repeating exactly the fallacy that Lloyd spends most of the time clearly and eloquently refuting: that the alternative to an explanation in terms of an adaptation is not that the feature is “incidental”: it’s a specific alternative causal explanation in terms of evolutionary factors other than adaptation for the trait in question. For which, in this case, there’s considerable evidence.
I’ve heard that sort of thing now and then from the younger generation of biologists and I just can’t understand how they don’t seem to understand that traits do not necessarily have to be selected. The misunderstanding seems to go in hand with the myth that species develop new traits in response to evolutionary pressure rather than evolutionary pressure weeding out fewer of the existing population which happens to have developed a particular trait – as though organisms are magical and deliberately make changes to their biology based on the environment. I’m sure everyone’s heard non-biologists spouting crap like “it’s OK if the earth warms another 6 degrees C, we’ll just all ‘adapt’.”
KG: “overall orgasmicity”. I’m filing that with “uterine upsuck” in my list of phrases to avoid at the dinner table. ;-)
—
I can’t say what the commenters on the Sandwalk post were complaining about. It seemed to be one person who. Saw. Two. Peaks!
Then again, I am biased, having read
Tits and ClitsMale Nipples and Clitoral Ripples (which is where this is *ahem* coming from).Since both of these eukaryotic cells still have to find a willing partner, and successfully complete the mechanics of genetic interchange properly, without knowing either cell’s propensity in these spheres, it is impossible to know.
Beccamauch
That’s an argument for sexual pleasure being adaptive, but not for the female orgasm being adaptive: things can be extremely pleasurable without leading to orgasm.
Also, does anyone think single eukaryotic cells experience orgasm?
If not, why do they ever bother with that messy sex thing?
@31 orgasm *feels* like a costly and mostly(majorly?) costly and in a energy ‘cost/income/outcome’ trichotomy dangerous adaptation overall, building social frameworks is perhaps a ‘excuse?’ but in single ‘eukareotes?’ with the infrastructure required it feels like a effective killswitch…
*Didn’t find out how to actually bend eucariote as a word.
My understanding is single celled eukaryotic cells have a different payout for sexual reproduction. Greater genetic diversity and fitness.
Didn’t you see that slut shiver with delight as she divided? Srsly, she loves that meiosis shit.
I have a question that I am not qualified to answer. So perhaps someone who has had both an orgasm and delivered a child vaginally could answer.
From external observations, the contractions of an orgasm, look very similar to the contractions of childbirth. Is there any co-relation between the endorphins released during an orgasm and the endorphins released during childbirth?
I don’t get it.
I agree with her main points: that we jump to adaptationist conclusions and cling to them (possibly like others might jump to goddidit explanations?) when there are other *evolutionary* explanations available; that how we frame the research question can insidiously bias the outcomes of the research. But I don’t understand something(s) about her example.
At about 18 minutes, she contradicts what she said earlier. First she said there is no correlation between sexual motivation (desire to have sex) and the proportion of time that sex results in female orgasm (see 2nd at 3rd bullets at 14:10. At 17:50 minutes she says that she and Simon don’t deny that relationship (“almost certain”). Well, I think this is an important point. If she’s willing to reject the null hypothesis despite the data in this case, I’m confused about the application of her philosophy of science in the broader case of her example.
I’m also confused about the implications of other primate species demonstrating female orgasm. It’s unclear what point she is making. Sure it could be a shared developmental constraints that makes muscle contractions similar between macaques and humans, but I see positive selection as an equally plausible explanation. The key is to test the ideas. You need variation to test such ideas. So wouldn’t it be most fruitful to examine female orgasm among species?
You aren’t reading it right. The bullet points at 14 minutes show no correlation between orgasm & evolutionary fitness — female orgasm has no effect on childbearing.
broboxley
Check it out.
#39 rq thank you
#38 PZ, thanks for the reply. It’s not obvious to me that I’m misreading it — she says “… or any other trait correlated to fitness;” and since she has no correlation beside bullet three (“female orgasm occurrence and interest in intercourse”), I would interpret that to mean that interest in intercourse is related to fitness. Thus I’m confused later when she accepts that orgasmability (TM) is related to interest in intercourse!
Aha! But in the previous slide she does qualify her meaning with “genetic correlation” rather than simple “correlation”. Is this what you mean? That is likely an important distinction. In my defense, the verbal transition between slides doesn’t make it at all clear that the qualifiers should be carried through.