[lisper]

Cooperation and symbiosis are very general survival strategies. They apear at all levels of the biological abstraction hierarchy, all the way down to mitochondria, which are almost certainly descended from what was once an independent organism. In fact, even a genome itself can be seen as a collection of mutually cooperating replicators. No intelligence is required for cooperation to evolve. It's a straightforward consequence of game theory.

[culi]

Yes! Cooperation seems to be just as fundamental, if not more, than competition. We wouldn't have gotten volcanic islands to break down into soil if it weren't for the partnership that is lichen. We wouldn't be able to digest a tenth of what we're able to eat if it weren't for our gut bacteria. We wouldn't have trees if it weren't for mycorrhizal fungi which over 90% of plants depend on.

There's a famous paper/framework called "Major evolutionary transitions in individuality" that sketches out a big picture pattern of major evolutionary advances in complexity following a surprisingly consistent pattern: As cooperation and division of labor strongly increase, selection starts working on larger entities. This pattern holds all the way back to the origin of life itself as things moved from self-assembling molecules to compartmentalized populations of molecules, from replicators to chromosomes, from RNA+enzymes to DNA+proteins, from prokaryotic cells to eukaryotic cells, from unicellular to multicellular, from individuals to colonies/superorganisms, and (possibly) onwards to more complex societies

https://www.pnas.org/doi/10.1073/pnas.1421402112

[lisper]

> Cooperation seems to be just as fundamental, if not more, than competition

Both are fundamental. You can't survive without cooperating, but you also can't survive if you try to cooperate with the entire biosphere because ultimately there is competition for scarce resources. If you don't assert yourself to claim your share of those, something else will.

[culi]

Yes, but does your kidney compete with your lung?

I would highly recommend you read through the paper. Alongside these "advanced in individuality" comes reduced (internal) competition.

I agree that both are important but competition only seems to be important at the very edges of what selection is acting upon while cooperation is truly "fundamental"

[lisper]

> does your kidney compete with your lung?

I don't know of any cases of direct kidney v lung competition, but competition among body parts is common. Sometime that competition is adaptive, sometimes not. Examples of adaptive competition are things like when under extreme circumstances (particularly cold or hunger) your body will sacrifice parts of itself to keep other parts going. Examples of non-adaptive competition are things like autoimmune diseases. Also, sometimes individual cells go rogue and stop cooperating. That's called cancer.

> competition only seems to be important at the very edges of what selection is acting upon

I guess that depends on what you consider "the edges". In the case of humans, selection produces intuitions about "us vs them". Those intuitions range from very closely drawn boundaries ("us" includes only my immediate family or clan) to very broadly drawn boundaries ("us" is my entire species, or my entire phylum, or all living things). In between are things like "us" is all members of my species with my skin color. But the extremes of this range are non-adaptive. Draw the boundaries too narrowly and you end up without enough genetic diversity in your in-group to drive out maladaptive mutations. Draw them too broadly and you end up defenseless against parasites and with nothing to eat.

[culi]

That's exactly my point. Competition at the fundamentals is called cancer. It's the exception, not the norm.

Your body prioritizing which parts to keep alive for the survival of the whole ship is not an example of competition. Competition would be if a body part actively attacked another body part. In this case, survival of the entire body will eventually benefit all body parts

> I guess that depends on what you consider "the edges"

The "edges" as thoroughly defined in the paper I linked. Major evolutionary transitions in individuality (METI). METI is a widely accepted framework in biology

[lisper]

> Competition would be if a body part actively attacked another body part.

I guess we'll just have to agree to disagree about this. I don't see a lot of daylight between "active attack" and starvation of resources. Just because your attacker chooses to lay siege to you rather than mount a full frontal assault doesn't make them any less of an attacker IMHO.

> The "edges" as thoroughly defined in the paper I linked.

Sorry, I don't see it. AFAICT the word "edges" only appears once in the paper:

"Evolution is a process of continuous change, and so we should expect blurry edges with a mosaic of features (1)."

[UPDATE] Oh, BTW, I think that paper is actually very good. Thanks for bringing it to my attention.

[LeCompteSftware]

This is a frustrating response to my comment. I am aware that symbiosis is universal. That's not what I'm talking about. I am talking about the specific and highly unusual behavior of crawling inside of a much larger animal's mouth and trusting it not to eat you. Cleaner fish are highly intelligent[1] and it appears that this intelligence is necessary for their niche:

- picking a good location for a cleaning station requires long-term planning and real strategic judgment;

- deciding which hosts to accept is a complex skill requiring some sort of rudimentary theory of mind + long-term development of social ties;

- like crows, cleaner fish are jerks who constantly try to screw each other over, so there is something of a cognition arms race.

I will add that the wrasse family of cleaner fish use rocks to smash open shellfish (i.e. they are tool-users), and they have very complex group strategies for raising their young. In fact I'm not convinced that wrasse evolved to be cleaner fish at all: they are natural scavengers and scum-suckers, perhaps cleaning stations are a form of cultural technology.

I would be extremely surprised if any of this was true for cone ants. I suspect that is more hard-wired, perhaps a local subspecies stumbled into a genetic fluke, and as you say due to game theory it is a local optimum this population has settled on. If this behavior were common like it is in vertebrates, we probably would have seen it earlier. But who knows? 20 years ago I would have thought "fish have a form of culture" is too ridiculous an idea to consider.

[1] Seriously: https://journals.library.columbia.edu/index.php/cusj/blog/vi... https://www.nature.com/articles/s41598-025-25837-0

[lisper]

> I am talking about the specific and highly unusual behavior of crawling inside of a much larger animal's mouth and trusting it not to eat you.

OK.

> Cleaner fish are highly intelligent[1]

Yes.

> and it appears that this intelligence is necessary

Manifestly not, at least not in general.

> for their niche:

That is an open question. Just because an unintelligent cleaner fish hasn't evolved doesn't mean it couldn't.

[fsckboy]

mmmm it's equally likely that mitochondria's precursors were self interested parasites or predators, whose negative effects were competitively neutralized by defensive host adaptations that exploititively colonialized them. No intelligence or cooperation is required for co-opt-ation to evolve. It's a straightforward consequence of game theory.

[lisper]

> it's equally likely that mitochondria's precursors were self interested parasites or predators

That is in no way at odds with what I said.