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"I've always enjoyed contemplating the inverse of this theory; what if we gained appreciation for music and other collective rituals because by acting out these rituals (as individuals), our collective tribe benefited. These rituals cause us individuals to 'tune' ourselves as a collective and as a result, the tribe has increased chances of survival."

This is called group selection. It's ironic that you mention it in response to this interview; Dawkins became famous by explaining the fact that group selection doesn't exist, and why theories like the one you've just suggested violate very fundamental principles of evolution. More: http://amzn.com/0199291152

Well said. Even more (no need to get a book out): http://lesswrong.com/lw/kw/the_tragedy_of_group_selectionism...

thanks for the tips - I've been meaning to check out 'The Selfish Gene'. I checked out the lesswrong.com article - I'm not sure that my argument is the same as what they are trying to disprove - it sounds like their models are based on individuals that collude or act altruistically in order to benefit collectively. I don't think that 'intention' is a good concept for understanding evolution in the first place. Also, from checking out the Wikipedia article on group selection, it doesn't sound like there is scientific agreement that this concept is disproved: http://en.wikipedia.org/wiki/Group_selection

I'll go and read The selfish Gene before I write more, but one more pesky comment about the experiment in the lesswrong.com article: I am suspicious of their conclusion that their case study disproves group selection. This does not seem to respect the vast scope of evolutionary time scale. Maybe group selection is like quantum tunneling - with large clusters of individuals, the chances of it happening are infinitesimal - you won't see it in the laboratory. But on an evolutionary time scale, infinitesimal chances do happen occasionally - and if they yield advantageous results, they will shape life's future. Maybe our love for music came about from freak genetic mutations that in fact didn't serve much purpose for individual survival, but this collective activity caused individuals to synchronize their behavior. Maybe this synchronization helps low-advantage/individual traits 'tunnel' probabilistically and exist long afterward because the same traits are high-advantage/collective traits. (?)

That math doesn't work out the same if the trait doesn't have an appreciable cost to the organism (the case he considered has one of the most extreme costs).

No, it's plausible that the rituals also benefit the individual. Group selection is nearly impossible if the thing that's good for the group is bad for the individual, but it's not clear that that's the case here.

But group selection is certainly not impossible. If you view a human as a population of cells, then cancer cells will tend to be group selected out.

"If you view a human as a population of cells, then cancer cells will tend to be group selected out."

Organism selection isn't a counterexample to the non-existence of group selection, because organism selection doesn't exist either. Selection pressure doesn't operate on species, populations, organisms, or even cells. It operates on genes. What appears to be organism selection is actually gene selection operating in the special circumstance that all of your cells were created by the same genome. This is also why bees, which will gladly commit suicide to sting you and protect the hive, aren't an example of group selection. The bees that sting you are sterile. The reproductive potential of their genes lies entirely outside of their bodies, so they're disposable. Their gonads are quite literally somewhere else.

So, I'll add the caveat that music could be adaptive in the sense originally described, conditional on a demonstration that people who enjoy similar music are sterile identical clones produced in bulk by the same mother.

I don't see how picking a small part of what I said and nitpicking on the wording helps here. But if you insist I will reword it for you:

> If you view a human as a population of cells, then GENES THAT ARE LIKELY TO RESULT IN cancer cells will tend to be group selected out.

And as I said it is also entirely possible that being good at music/rituals improves an individual's chances of survival, as well as the chances of survival of the tribe. In this case the arguments against group selection don't apply.

Group selection is definitely an effect, but is a small effect compared to individual selection. So if traits that are good for the group are at odds with traits that are good for the individual then the traits that are good for the individual are likely to "win".

Even in an ideal situation where a mutation has a "pure" benefit to the group, with no other drawbacks to the mutated gene, it will not be selected for. Selection pressure is a scarce resource. It protects existing adaptations from the ever-present entropic decay of mutation. Genes that are not selected for, relative to the other genes in the population, will reliably fall apart due to lack of maintenance and their effects will disappear. A gene must continually justify its survival by outperforming competing mutant alleles. It's just not true that group selection is merely weak, or a secondary effect occurring only when genetic selection allows it. The aggregate contribution of group selection to a gene's survival is literally zero.

I'm not arguing that music isn't adaptive. It's plausible that its adaptive value is to display to potential mates how well one's brain processes rhythm, which is useful for any number of physical activities as Pinker points out in the interview. But that's different than being selected for because it makes the group more cohesive. It may even, in fact, make the group more cohesive, but this will have nothing to do with why it was selected. This would have to be a happenstance byproduct, and thus not a plausible explanation for the existence of a complex adaptation like music. It would no more explain music than having your flowers watered would explain why it's raining.

So in what way is cancer not an example of group selection? Cancer cells reproduce more quickly, so in a sense they are fitter. However, on a large scale, the scale of complete groups (group = human being), they perform poorly because they kill the group. In other words, if the universe consisted of one giant human being then the cancer cells would definitely win. However, because of the group structure and the selection for complete groups, this doesn't happen.

I agree that within a group, group selection doesn't matter (duh). However, if you look at the aggregate of groups, after some time the groups with the group benefiting genes still exist while the other groups have died out. The groups that still exist will spawn new groups, etc, the standard evolution tale.

Consider this extreme case:

We have several groups. At every time step the group has a chance of being annihilated. An individual in a group can either have gene A or gene B. If an individual of a group has gene A then the chance that the group as a whole is annihilated is decreased. If it has gene B then this chance stays the same. Each individual in the group has a chance of reproducing. Once the group is above a certain size, it splits into two groups.

Now I'm sure you agree that gene A will be selected for relative to gene B, even though gene A gives no benefit to the individual relative to the other individuals in its group.

In the aggregate of groups, a gene with a huge benefit to the group and a slight disadvantage to the individual can, in the aggregate of groups, outperform a gene with a slight benefit to the individual but no benefit to the group. Sure, the conditions have to be just right for this to happen, but it does happen (e.g. cancer cells). So you can't say just because "group selection is impossible" that group selection doesn't happen in populations of animals. You need to analyze the particular situation to determine this.

It is possible, in principle, that rituals are another example of this.

You're right. I apologize for having wasted your time and humbly award you three karma points.

Seems unlikely. While music may be beneficial to a collective, a collective would not be able exist without some form of communication. It appears that the generation and appreciation of music relies on a number of genes that seem unlikely to have evolved purely for music. The selection pressure would almost certainly be stronger on very basic levels of communication before any higher levels of tribal organisation, if purely because they can't exist without the basic selection on communication.

A beehive or an ant colony is actually one organism, from the point of view of evolution. The individual insects are genetically identical within a collective.

No it isn't, you should read The Selfish Gene by Dawkins. There's a chapter explaining that this is a myth with little grounds in reality.

There's a lot of backstabbing and competition that goes on within individual hives of the social insects.

I've read it, a long time ago. IIRC, there is competition among the very few breeders, but the non-breeding workers are in fact identical. The social cohesion parent was talking about happens among the workers.