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by wahern 1938 days ago
Even today there is no genetic model that can explain the emergence of human altruism--non-kin eusociality. Eusociality among kin, such as naked mole rat sisters and bee clones, is trivially modeled using selfish gene theory. But no one has yet proposed a stable model for its emergence and persistence outside close kin groups. And in fact humans are the only species that exhibit this phenomenon. All other forms of cooperation in nature can be explained by selfish gene theory (that is, individualized sexual selection benefit directly commensurate with the individualized risk), or as non-stable outliers (e.g. a cat befriending a bird).

Apparently Darwin believed in a group selection-type model, as still many do, even though its been disproven (at least refutations have never been overcome). And if you believe in group selection I suppose one would find it easy to rationalize racial models, Victorian or otherwise, especially if you were born on an island or otherwise believed substantially physically segregated human groups--and therefore segregated sexual selection dynamics--was typical. Indeed, even today anthropologists are severely allergic to the possibility of rapid gene flow, especially back flow, of specific genes. The notion that there could have been back flow of genes into Africa is anathema, which makes it easier even for scientists to conceptualize humanity as groups of islands, rationalize group selection theories, and be more credulous of narratives whereby some groups "advance" faster than others--because good genes wouldn't individually leak out, and bad genes wouldn't individually leak in.

But that's only a partial defense of Darwin. The very fact that humans are the only species to exhibit inexplicable non-kin eusociality, while all these proposed models would apply equally well to any other species (suggesting they're incomplete, because mass selfless cooperation is quite obviously a powerful group advantage if attainable), hints at a massive gap in our understanding of our own evolution, counseling against strong positivist claims about how human evolution worked and continues to work. IOW, Darwin could have been more humble.

2 comments

That altruism is selected for highlights what was long selected against. The non-selfish and even selfless or self-sacrificing behaviors seem a likely consequence of eons of semi-just capital punishment as a societal level selection mechanism.
You are looking at the wrong level. It is tribal reproduction that is being optimized. An individual is just a cell of that tribe and doesn’t even need to reproduce as long as the tribe reproduces. This is just like how your hair doesn’t have to reproduce as long as you do. Also, it isn’t your genes that matter but the relative distribution of traits in a population.

https://waitbutwhy.com/2019/08/giants.html

Look at the related reading.

Look at the Catholic Church.

Again, models of group selection have been refuted time and time again.

Group selection may still be true, but there's neither persuasive evidence nor persuasive models for that. It's merely an assertion. Which is my point. We don't know. All these theories are just building castles on sand.

Obviously there are limits to human cooperation. And of course there are innumerable concordances between what we see in society (i.e. "tribal politics") and various group selection theories. But without an anchor in genetics these theories are dangerously close to--if not patently--political or religious beliefs.

To reiterate, there is no established genetic model that links individual sexual selection pressures to group evolution, in the sense that evolution can select for group traits without a pathway where the genes advantage each individual, and do so incrementally as the gene spreads. (Because genes don't magically appear all at once in the entire group, and even they did you're still left with the stability problem because you also need to explain--at an individualized sexual selection pressure level--how cheaters are suppressed.) Group selection models are merely based on the tautological presumption that genetic sexual selection acts at the level of groups.

Furthermore, there's no reason to believe group selection must be true in order for human altruism to have emerged. That is, it's not the only option. Though the alternatives (e.g. Joseph Jordania's theories for the emergence of articulated speech, which also explains the emergence of empathy--two birds, one stone) haven't been shown with concrete evidence either. Though at the very least they get extra points for working with selfish gene theory, rather than in seeming contravention of it.

So without knowing the precise genetic dynamics of altruism (neither how it emerged nor how it persists, which isn't necessarily the same question), we can't make any strong claims about its contours, limitations, potentiality, etc, beyond hand-wavey inferences from observation, which are highly susceptible to our own prejudices.

https://waitbutwhy.com/2019/09/stories.html

I don’t know what sort of evidence or experiment you are looking for.

It’s even possible that it isn’t stable and we are undergoing evolution now.

Here's the crux of that article:

> At some point between 150-person ancient tribes and New York City, human evolution jumped off of the “survival of the fittest biology” snail and onto the “survival of the fittest stories” rocket.

If we ignore alot of the hand-wavey stuff (debates on the viability of various models often come down to hard math--i.e. the rate of selection benefit drop-off as a function of kin distance--and thus you need that level of specificity to make a persuasive case) one of the root assumptions up to and including this point is that intelligence is driving fitness for group participation. But that only begs the question of what's driving intelligence.

In 2021 the notion that human's are unique benefactors of high-order intelligence is quaint. We see intelligence everywhere. In fact, as far as we can tell, at least for the past several hundred million years (dinosaurs, mammals, etc) intelligence arises easily in nature, at least to the extent it's ecologically advantageous to the individual.

In the above story, it seems that incrementally increased group intelligence precedes incremental increased altruism. But if that's so, why don't we see more human-magnitude intelligence everywhere, considering that incremental increases in intelligence come rather quickly in higher order species. Alternatively, intelligence increases incrementally on an individualized basis because it's a better fit for a more cooperative society, which again only begs the question of why the society became more cooperative. And that question needs concrete answers other than "because it obviously benefits the group."

I can't really tell how strongly the article depends on group selection theory. On its surface it doesn't, but arguably it still subtly does. In any event, it's not an answer. It's just another plausible narrative. Better than most narratives, but it doesn't even come close to the level of scientific specificity required to draw meaningful conclusions about the evolution of human altruism or intelligence. Joseph Jordania has a much better narrative; far more specific (perhaps too specific, and thus likely wrong in the strictest sense), and one with more concrete predictions (e.g. that prevalence of speech impediments will be lower in East Asian populations, due to the gene(s) for articulated speech arising in East Asia and back migrating to Africa and Europe).

> I don’t know what sort of evidence or experiment you are looking for.

1) One that doesn't have large conceptual gaps. 2) One that makes precise, relevantly falsifiable predictions that can be (and iteratively are) confirmed.

> It’s even possible that it isn’t stable and we are undergoing evolution now.

Indeed. But if we had a concrete understanding of our evolution, we'd have a much better idea not only if that's the case (continuing evolution is a good bet), but what those fundamental dynamics look like, as opposed to high-level, squishy observations about how they manifest.

Actually, I have a movie script idea about a group of scientists figuring that all out and concluding that the evolutionary pressures sustaining human altruism are rapidly receding, threatening not only the collapse of human society but in turn human intelligence. The group of scientists endeavor to use genetic engineering to "artificially" sustain altruistic tendencies--a metaprocess which if successful could be seen as a sort of next level evolutionary leap in higher-order life. But a group of evil scientists surreptitious infiltrate the program with the intention of creating a world of slaves (highly intelligent, but focused only the well-being of the rulers), begging the question of how the ruling minority could sustain itself with such malevolence. And the drama plays out thusly, perhaps leaving the question unanswered as to whether the good scientists win, or if not whether the evil scientists are simply acting out the prediction of an inevitable end to humanity and human-scale intelligence.

I think that we should be able to test this in a simulation.

I think the crux of the idea is that if a group of people stop fighting for a bit amongst themselves and instead wipe out another group, then the other group will no longer reproduce.

Any mechanism to allows this to happen more effectively will reproduce itself. Tribal thinking is supposedly one such mechanism. So genes/culture that will promote tribalism are selected for to some extent.

Human history seems to be the natural history of this.