In the Roger Scruton on altruism thread, some commenters have expressed confusion over the evolutionary explanation of altruism in ants. If workers and soldiers leave no offspring, then how does their altruistic behavior get selected for?
The answer is simple but somewhat counterintuitive. The genes for altruistic behavior are present in both the workers/soldiers and in their parents. Self-sacrificing behavior in the workers and soldiers is bad for their copies of these genes, but it promotes the survival and proliferation of the copies contained in the queen and in her store of sperm. As long as there is a net reproductive benefit to the genes, such altruistic behaviors can be maintained in the population.
Selfish genes, altruistic individuals.
Let’s dedicate this thread to a discussion of other counterintuitive evolutionary truths. Here are some of my favorites:
1. The classic example of sickle-cell trait in humans. Why is a disease-causing mutation maintained in a human population? Shouldn’t selection eliminate the mutants? Not in this case, because only the unfortunate folks who have two copies of the allele get the disease. People with one copy of the allele don’t get the disease, but they do receive a benefit: improved resistance to malaria. In effect, the people with the disease are paying for the improved health of the people with only one copy of the mutation.
(Kinda makes you wonder why the Designer did it that way, doesn’t it?)
2. In utero cannibalism in sharks:
Shark embryos cannibalize their littermates in the womb, with the largest embryo eating all but one of its siblings.
Now, researchers know why: It’s part of a struggle for paternity in utero, where babies of different fathers compete to be born.
The researchers, who detailed their findings today (April 30) in the journal Biology Letters, analyzed shark embryos found in sand tiger sharks (Carcharias taurus) at various stages of gestation and found that the later in pregnancy, the more likely the remaining shark embryos had just one father.
(Kinda makes you wonder why the Designer did it that way, doesn’t it?)
3. Genetic conflict between parents and offspring. Here’s a great example from a 1993 paper by David Haig:
Pregnancy has commonly been viewed as a cooperative interaction between a mother and her fetus. The effects of natural selection on genes expressed in fetuses, however, may be opposed by the effects of natural selection on genes expressed in mothers. In this sense, a genetic conflict can be said to exist between maternal and fetal genes. Fetal genes will be selected to increase the transfer of nutrients to their fetus, and maternal genes will be selected to limit transfers in excess of some maternal optimum. Thus a process of evolutionary escalation is predicted in which fetal actions are opposed by maternal countermeasures. The phenomenon of genomic imprinting means that a similar conflict exists within fetal cells between genes that are expressed when maternally derived, and genes that are expressed when paternally derived.
(Kinda makes you wonder why the Designer did it that way, doesn’t it?)
Can readers think of other counterintuitive evolutionary truths?
Addendum
4. Mutant organism loses its innate capacity to reproduce and becomes a great evolutionary success. Can anyone guess which organism(s) I’m thinking of?
That’s reductionist silly! ; )
http://www.youtube.com/watch?v=-M-vnmejwXo
Gregory,
How do you think the behavior of the sterile castes is encoded, if not genetically? Does God implant it in each of their little ant brains?
I don’t think there has been any actual confusion about this.
keiths:
Neil:
Have you read the thread?
Take a look at this comment, for example:
Yes.
There’s no confusion there.
Disagreement is not confusion. There is often disagreement among scientists.
That particular comment does not disagree with the view that the particular behavior evolved. It is questioning whether “altruism” is an appropriate name for it.
I’m happy to express confusion over the evolutionary explanation of altruism in ants. Joe F. indicated that he doesn’t understand this himself, because it isn’t actually understood at present by anybody. Joe knows a hell of a lot more about this stuff than I do.
So yeah, I’m confused about the evolutionary explanation of altruism in ants, and I doubt anybody actually has one right now. It’s nice that geirths here isn’t confused about it, because, I guess, he’s not confused about anything. But he’s special that way.
Neil,
Petrushka’s confusion (and yours, apparently) is in thinking that altruism somehow requires unique mutations in sterile individuals:
The important mutations are not the ones occurring in sterile individuals, but rather the ones that occur in the queen or the drones and are passed down to their offspring, including the sterile castes. Those mutations can affect the behavior of the sterile castes, including by causing altruistic behavior.
As I said in the OP:
This isn’t controversial at all among biologists.
Becoming more fit for its niche may lead to a species’ extinction during extraordinary events.
Often, becoming large is a good evolutionary response to predation, and it frequently allows for domination of resources. Elephants didn’t have many predators before humans became pretty good at killing them, and they can knock trees down to eat their leaves. Presumably matters were similar for large dinosaurs.
Then comes the asteroid, and little mammals scurry into the ground, while being able to eat anything, and the big dinosaurs freeze and starve.
And yes, this is a fairly common counterintuitive snag for creationists, who usually have avoided learning anything much about evolution.
Glen Davidson
walto,
You’re badly misunderstanding Joe’s comment. He isn’t questioning the genetic explanation in the slightest:
The rest of his comment deals with differentiation, which is a distinct issue:
It’s analogous to human body cells that have the same genotype but develop into completely different tissues depending on local signals in the body.
Absolutely. That’s why you should hesitate before dismissing his carefully-worded statement:
Another nice example of ant altruism:
Heroic altruistic ants face death alone to save colony
‘Heroic’ is a bit of a journalistic stretch, but the science is interesting.
Firstly, you are presuming that I agree with petrushka. I don’t. I am neutral on the position he is arguing.
Secondly you are, in effect, arguing that you can get an ought from an is. Petrushka is expressing his opinion on whether the word “altruism” should be used this way.
Glen:
Good example.
Overspecialization is a similar pitfall. Eating bamboo and practically nothing else is a great idea for a panda — as long as there is plenty of bamboo. Not such a good idea when bamboo habitat suddenly comes under threat.
The high extinction rate is a testament to evolution’s lack of foresight.
Neil,
Where did you get that idea?
Right, and his argument is based on confusion about the biology and about the meaning of ‘altruism’ as used in biology. Take a look at his comment again:
The ability to “pass on any unique genes” is not a criterion for altruistic behavior. Also, petrushka seems unaware that the mutations behind altruistic behavior don’t have to happen in the sterile individuals. They happen in the queen or in the drones and are passed down to their offspring, including the sterile castes.
Bullshit.
People are allowed to express opinions disagreeing about meanings.
I’ll be the skeptic about this one.
It is like saying that people in a leper colony were being altruistic. However, they were actually coerced.
We do not know enough about ant social structure to know to what extent there is coercion requiring this behavior.
Neil,
The article covered that:
Neil,
Of course they are. That doesn’t change the fact that petrushka is confused about the biology and about the meaning of ‘altruism’ as used by biologists.
He writes:
That’s not correct. It does make sense for biologists to describe workers and soldiers as altruistic. Their behavior fits the biological definition of altruism perfectly, and this in no way depends on their ability to “pass on any unique genes”.
Do you even know what the words “dismissing a statement” mean? Let me give you a hint. I am not and never did “dismiss” anything Joe said. OTOH, I dismiss almost everything YOU say, because you’re generally full of shit. Your post above is one more classic example of that.
W
walto,
Read Joe’s words:
His statement is correct. Your discomfiture is irrelevant.
As far as I know, lepers were not carried away by others.
You cannot conclude that there was no coercion, based on the evidence given. We do not know enough about ant social structure to be able to recognize whether there was coercion.
What other forms of ant coercion are you thinking of, Neil?
I added a #4 to the OP:
I am not thinking of another form of coercion.
I am suggesting that we don’t know enough to rule it out.
Every scientific conclusion is provisional, Neil.
The researchers did the sensible thing. They found no evidence for coercion, despite looking for it, so they provisionally concluded that there was no coercion.
I’d say, for the moment, that the research protocol described by the paper was specific enough to rule out the possibility that they were physically carried off.
And even if they were “chemically coerced”, it would still be altruistic behaviour. It is their evolved sensitivity to the chemical, after all, that is the point of focus, if this is the case. Their bodies are carrying out an action that reduces their own life expectancy in favour of the life expectancy of kin. Biological altruism isn’t concerned with motives, but with effects only.
So you would count a leper colony as an example of biological altruism ???
If the diseased animals remove themselves from the general population with the effect of reducing their own life expectancy, reproductive chances, etc, in favour of those of their non-diseased kin, then yes.
Addendum
If they are forced from the general populace, then I’d say
nohm. It would depend on the sort of coercion. If they were physically moved and isolated through appied force, there probably wouldn’t be evidence for any altruistic tendencies. If the mechanism is social coercion, there might still be: the focus of selection would be the animal’s responsiveness to social stimulae.Your mind-reading powers are amazing, Keith.
Alan,
Let me fix that for you:
keiths,
Dear Kiet,
Here’s my post again that you say is “dismissive” of Joe:
Please highlight the dismissive (of Joe) part for me. (Obviously, it’s dismissive of YOU, for reasons of which everyone here is aware). [Joe or anyone else here who’d like to enlighten me about my dismissiveness in my remark, please feel free to do so.]
And while we’re nicely asking questions of one another here, Mr. Cheerful Acknowledgement, I’m now asking you a fourth (or is it fifth?) time: Did you or did you not notice my posts, written subsequent to those you have (repeatedly) linked, in which I clearly indicated that I had no interest in increased moderation, prior to your (again repeatedly) posting that I DO want more moderation? And on the same topic, did you happen not see the post in which I said to Alan I was not in earnest about the orange highlighting biz, prior to your (again repeatedly) making links to my prior post about that highlighting?
These aren’t hard questions, keit: I mean, the answers are indicative of something untoward about your character, but they’re easy to answer.
Yours truly,
The guy who the poster known as ‘keiths’ cheerfully asserts not to “care if a few Yids get jailed for protesting the draft [because] they’re Yiddish-speaking, and socialists, and their liberties aren’t important the way [his] are”?
PS to Neil: I think the intentional misrepresentations of the kind I refer to above suggest problems with your Aspergers diagnosis. I mean, intentional misrepresentation is not a symptom of that, is it? I admit that I had questions myself as between nuts and prick, but it gets clearer and clear to me the longer I’m here that the guy’s just a douche.
Walto, you said:
Although your comment does not seem dismissive of Joe’s, I also can’t agree that Joe is “expressing confusion” over the evolution of altruism in ants:
As I read it, Joe is saying merely that the signaling involved in differentiation is not well-understood – not that the evolution of altruism itself isn’t understood. In general terms, the evolution of (kin-)altruism (or whatever the phenomenon of sterile workers/soldiers sacrificing themselves to the benefit of the nest and queen should be called) in ants is very well understood, even though details varying from species to species aren’t always modeled. Given the discussion, Joe’s comment wasn’t exactly on-topic (but informative nevertheless, of course).
walto,
This obsession, and all this bitterness, can’t be good for you. You realize that, don’t you?
Put aside for the moment whether I am the Great Satan incarnate, and just ask yourself whether your reaction to the situation is making your life better or worse. You certainly don’t appear to be enjoying yourself. Why react this way if it’s making you so unhappy?
As you know, I’m reading your book on meditation and mysticism right now, and I can’t help but imagine how your serene guru character Rabi would counsel you if he were aware of the uncontrolled anger and vitriol you’ve been pouring into the pages here.
I know it’s been a decade since you wrote the book, but don’t you still desire equanimity and serenity? How does all this bitterness help?
Gralgrathor,
I’m afraid a growing antipathy to Keiths’ blog persona may colour some of walto’s and my responses.
There are interwoven issues here.
Communication between humans. Could do better!
What’s going on with ants. Endlessly fascinating. I find myself watching columns of carpenter ants to the distraction of what I should be doing. How the colony is a mass of pheromone signals dancing around like nerve impulses. (Yes limited analogy, I know) and how development of castes appears to result from exposure to the right cocktail and yet each individual almost on behavioural rails… well, it’s just fascinating.
What meaning is conveyed by “altruism”. Come to that, what meaning is conveyed by “genetic””.
ETA Just introducing a grass blade produces an interesting threat posture in the soldiers.
ETA2 Here’s an article suggesting how ants may have evolved from a non-social ancestor that is also ancestral to extant mud-dauber wasps. (hat-tip Carl Zimmer)
When did you stop beating your wife?
Alan,
The analogous question would be “Don’t you still love your wife?”, not “When did you stop beating your wife?”
Why not slow down and think before clicking ‘Post’?
Because then I’d have no mistakes to admit! Plus I don’t have much time to spend here anyway.
Alan:
These are standard biological terms. Why are you asking to be spoon-fed when Google is available?
Biological altruism
Genetics
Alan,
I don’t think we need to worry about that. 🙂
Alan Fox,
Another interesting perspective on ant colonies is that of emergent complexity. The signal/response mechanisms in ants may be quite simple, but the result is, like you said, almost like a single nervous system.
Gralgrathor,
That’s right. Walto is conflating the two.
But he wasn’t being dismissive; it was merely a misunderstanding – one which isn’t entirely surprising, given that Joe’s original comment was not actually a response to the question he was asked.
I think he does not get intended meanings. It looks as if he is reading in a very mechanistic manner, a kind of algebra-of-dictionary-definitions, and missing what is actually intended.
I think it’s always better to let people speak for themselves. keit was annoyed and concerned when Joe was asked about this stuff, and since Joe posted keit has clipped that response, interpreted it in a way that he believes supports whatever crusade he’s currently on against Neil and Alan, and also weirdly represented my remark about that post as dismissive.
I think it would be much better for Joe to come on and say himself whether he himself believes there is currently a good evolutionary explanation of soldier ant altruism (and also whether he thinks my comment was dismissive of anything he said), instead of having Mr. Cheerful Acknowledgement continue to represent what I, Alan, Neil, Joe, etc. believe. Because when that happens, there is lying.
And BTW, it’s pretty obvious why he won’t answer those two simple questions of mine. With either a yes (he knew), or no (he didn’t know), response, he’s a dick. I mean, I wouldn’t want to answer if I were him, either. But that’s the kind of swamp one gets into when one acts the way he does.
Yeah, I don’t think so. I think he’s quite lawyerly about these misrepresentations. Literal when it helps his “case”; broadly interpretive (“dismissing”, “Yids”) when he thinks that works better for him. The pathological part is the absolute need to “win.” It destroys any hope of nice discussion or communication here. There’s just “debating” interspersed with self-congratulations.
HAHAHAHA
I hesitate to get in the middle of this, but
is obviously wrong if said ants are sterile.
As others have noted, the “soma vs germline” analogy is more apt. We are left with a more-heat-than-light semantic argument over the application of the word “altruism” to actors who can leave no progeny.
keiths,
mitochondria (& plastids)?
Aaaaaarggghh! 🙂
DNA_Jock,
Enter at your own risk. 🙂
No, because sterility itself is part (an important part!) of the altruism (although workers sometimes “cheat” by producing their own eggs, as Zachriel pointed out earlier).
You could, if you chose, castigate mathematicians for using the word ‘prime’ to describe numbers. You could argue that some other word was more appropriate, and you could insist on using that word instead. None of that would influence mathematicians, of course, and it wouldn’t change the truth of everything that has already been demonstrated regarding prime numbers.
It’s the same with ‘altruism’. You can argue all you want that a different word would be better, but biologists have settled on ‘altruism’ for good reasons, and the truths they have discovered about biological altruism remain true even if you would prefer that they had chosen a different word.
The sterile castes are altruistic according to accepted biological meaning of the word, and the number seven is prime according to the accepted mathematical meaning of that word.
I’m going to stay out of this. I don’t see my point being addressed.
I suggested a possibly eccentric or private definition of altruism and have no great desire to force it on others. I believe I am in agreement with many mainstream biologists in thinking the level of selection is the colony, and that for the purpose of thinking about selection of behavior, the sterile cast is not comprised of reproducing individuals.If they die fighting, they are behaving like white corpuscles.
They are not altruistic (in my sense of the word) because their death maximizes the prospects of having their genes passed on.