"Doesn't this count as a case of group level selection?"

Yes, when it works. Divide the population into smaller groups with strictly limited breeding between groups, and that's one way that segregation distorters can be limited.

Better mechanisms might arise too, but until they do this is what you've got. There might be some other advantages to a population divided into small groups with limited interbreeding, too.

And once you have a population divided that way, it leaves the possibility for other group selection. However, rats are mammals, and mammals are a small minority group that are unimportant in the bigger scheme of things. How often are species divided up like that?

'I would still be loath to call it "evolved to death". Where is the "evolution"?'

It happens because of a change in gene frequencies. That's what evolution is defined as -- changes in gene frequency. The mutant allele spreads and takes over. The population dies, but that doesn't keep the mutant allele from taking over among survivors while there are survivors.

Someone said the mutant allele isn't competing with X chromosomes. It's competing with both X and Y alleles. The mice start out with on average 3 X alleles per Y allele. At the end it's 1 X allele per mutant Y allele.

'Too bad, so sad. If there was an "evolution fairy", she would have designed a better machinery of genes.'

There may be a better machinery sometimes. The examples we have of segregation distorters may be examples where the better mechanism has broken down.

In the absence of better mechanisms, this sort of thing can happen. It's possible to get mutations which are selected and which spread even though in the long run they are bad for the population as a whole.

Analogously it's possible to make a lot of money in a free enterprise system while benefitting nobody but yourself, barring mechanisms to prevent that -- the "invisible hand" doesn't necessarily work to do what Adam Smith said it can do.

Mark, altruists have to deal with their costs too.

It's possible for an altruist to value the thousandth altruistic meal as much as the first, but as his resources shrink the value of the alternatives rises. If I provide meals for a hundred thousand starving people and then I have nothing left and I become a starving person myself, that isn't good. At some point I want to keep enough capital to maintain my continuing ability to feed starving people.

I'm not claiming that it's true that no altruist experiences diminishing returns, or even that there is an altruist who doesn't experience diminishing returns. But the behavior doesn't prove that there couldn't be, and so this isn't a killing blow.

Douglas, in *principle* you ought to consider the entire state of the future universe when you set a terminal value. "I want my sister not to be killed in the next few weeks by flesh-eating bacteria" is a vague goal. "My sister not being killed by flesh-eating bacteria because the world fell into a black hole and tidal effects killed her" is not an adequate alternative.

In practice we set terminal values as if they're independent of everything else. I assume that giving my sister penicillin will not have any side effects I haven't considered. As far as I know she isn't allergic to penicillin. If it will bankrupt me then that's something I will consider. I assume the drug company is not sending its profits to support al qaeda unless somebody comes out and claims it is and the mass media take the claim seriously. I assume the drug company won't use my money to lobby for things I'd disapprove of. I completely ignore the fact that my sister's kidneys will remove the penicillin and she'll repeatedly dose her toilet with a dilute penicillin solution that will encourage the spread of penicillin-resistant bacteria. If I did think about that I might want her to save her urine so it could be treated to destroy the penicillin before it's thrown away.

In practice people think about what they want, and they think about important side effects they have learned to consider, and that's all. If we actually had a holistic view of things we would be very different people.

Brendon, I find your reasoning plausible. I don't know how true it is. I don't want to give myself pernicious anemia to test it, so I'll settle for saying it looks plausible.

If you have a vitamin deficiency, and you get a dose of the vitamin that makes you somewhat less deficient, will you feel better within a few hours? If so then it might be reinforced. On the other hand, one single experience of nerve poisoning a few hours after eating a particular new food can be enough to establish a lifelong distaste for that food.

Brendon, you can't expect a learning system to quickly get an exact solution to a problem in N simultaneous equations. But when improvements result in a sense of well-being, they might tend to gradually zero in on solutions. So for nutrition you need sufficient energy and your body might have pre-programmed goals for repair and growth, and whatever helps meet those targets could provide that sense of well-being that announces something worked.

Simpler than having thousands of individual goals programmed in.

Just as an aside, fitness maximizers usually have to accept a finite population size in a finite biome with a finite carrying capacity. There's the possible goal of expanding into the galaxy and neighboring galaxies, but in the short run we have a finite carrying capacity.

And a fitness maximizer that is too successful has to accept it needs to preserve a lot of diversity in its gene pool or else face problems that would essentially reduce carrying capacity.

A conscious fitness maximizer at some point must realise that it survives by maintaining its numbers in a diverse population, rather than maximizing the frequency of its genes.

Douglas, your ideas are reasonable but unproven.

It certainly makes sense that new proteins with new functions should arise by recombination among old proteins with old functions. Start with functional groups that do things -- hold a calcium ion, hold a magnesium ion, fit to a lactam group, etc -- and fit them together in just the geometry that gets a result, and then fiddle with the details to change that geometry slightly. Sure, that makes sense.

And to get brand new protein structures you need to evolve them special -- to get selected starting with a protein that has a different structure you need to go through intermediate stages that are likely to have no function at all. But if the protein is under selection that won't happen, and if there's no selection it's sill quite unlikely.

So it's plausible there should be some mechanism to do all that.

However, the trouble here is that this mechanism would have to be mostly inactive. Do we create novel new proteins every generation? Every hundred generations? Not as far as I know. What maintains this mechanism that produces a good result in one individual per thousand generations (maybe), and produces no result or bad results the rest of the time? It would have to be a side effect of something else, something that does get used a lot. And that may be possible, but would you expect it to be the same mechanism in prokaryotes and eucaryotes? We haven't observed it yet in that case. So two different mechanisms, like they have vastly different ways to have sex.... And we still haven't particularly found those mechanisms.

I don't regard your tuberculosis story as useful. OK, lots of things are preadapted toward making certain discoveries. But not other discoveries.

Sure, it isn't random. But the assumption of randomness was a mathematical convenience. Mutation shouldn't be random, There's been 3 billion years of selection to encourage mutation at the times and places it does the most good -- to the extent that organisms can predict that.

There's a lot about the way populations respond to natural selection that isn't known yet, there are exciting discoveries waiting for us. You and I both have hints about what those discoveries will look like. But the discoveries haven't been made yet and we're only guessing about them at this point. I can guess pretty well about some genetic mechanisms that would increase the rate of evolution, but I can't guarantee that nature hasn't found even better mechanisms that outcompete the ones I imagine.

Billswift, after thinking it over some I'm surprised how much one person could do, if they knew not to follow any blind alleys. Like, you could do all the experiments needed to support Maxwell's equations in a reasonably short time if someone helped you set up the equipment.

It took a lot of people a long time to do it, but that's because they didn't know what they were doing ahead of time.

I don't know where the limits would come but they might be a lot broader than I first thought.

"I doubt a person who now found themselves in this situation would develop this revulsion."

By about the second generation a lot would. They would mostly be descended from people who hadn't used them. There is a minority that has a revulsion for condoms now. The idea of giving up practically your only change to have children, deliberately, would start seeming strange when everybody in the world had parents who hadn't done it. Cultures change faster when that happens.