Not just mites, we’re absolutely covered and full of commensal organisms. What’s really interesting is how specialized these organisms have become, like the difference between body and head lice. We have critters socialized to just our eyebrows and eyelashes, others only live in apocrine sweat glands, etc.
Even before you get to the literal kilograms of bacteria, fungi and other fauna in our guts we’re a whole world unto ourselves.
There are many Garra rufa subspecies that were the source of compounds used in treating modern autoimmune and skin disorders.
The fishes histories go back thousands of years. As a species it is super interesting... some evolved in hot-spring conditions that would simply cook most other animals. =3
Because there hasn’t been enough time and the ecological niche is non existent… ?
However… upon further inspection, one could argue that the micro biome is full of beneficial micro organisms that have evolved to fill this niche…
[1] Staphylococcus epidermidis
This is one of the most abundant and beneficial bacteria on human skin. It produces antimicrobial peptides and metabolites that inhibit the growth of pathogenic bacteria.
[2] Cutibacterium acnes
Despite its association with acne, this bacterium actually plays an important role in skin health by producing propionic acid, which helps maintain skin pH and prevents overgrowth of harmful organisms.
[3] Corynebacterium species
Various corynebacteria colonize the skin and produce lipases and other enzymes that help break down sebum (skin oils) and maintain healthy skin conditions.
[4] Malassezia species
These yeasts are abundant on skin and help regulate the skin microbiome, though they can sometimes cause issues in excess.
This is very cool, and quite surprising. Cleaner fish are thought to be among the most intelligent fish because of the complexity and danger of their feeding strategy: it takes careful planning and quick thinking. But they aren't tied to any particular species of host or general tactic; naively I imagine cleaner fish are more versatile and adaptable than cone ants.
It would be interesting to learn if this occurs with other species of ants. I suppose until now nobody thought to look.
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.
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
> 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.
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"
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.
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
> 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.
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.
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.
this is no surprise to anyone who has read dougal dixon's 'man after man'
The full paper described in the article is available here:
https://pmc.ncbi.nlm.nih.gov/articles/PMC13070876/
Mark W. Moffett. The First Cleaner Ant? A Novel Partnership in the Arizona Desert. Ecology and Evolution, 2026; 16 (4) DOI: 10.1002/ece3.73308
why haven't any animals adapted to this role for humans!
In a Sense, cats did actually. Not through direct contact, but by getting rid of mice and rats that infiltrate food storage.
Cat’s will also literally try to clean you as well!
Plenty of bacteria lives in your guts feeding on your food and generating useful by-products.
How do you know they didn't? When was the last time you just let bugs spend time on you?
There are more mites specialized to live on your eyebrows skin than many like to think about. =3
Not just mites, we’re absolutely covered and full of commensal organisms. What’s really interesting is how specialized these organisms have become, like the difference between body and head lice. We have critters socialized to just our eyebrows and eyelashes, others only live in apocrine sweat glands, etc.
Even before you get to the literal kilograms of bacteria, fungi and other fauna in our guts we’re a whole world unto ourselves.
We just don’t usually notice.
There are many Garra rufa subspecies that were the source of compounds used in treating modern autoimmune and skin disorders.
The fishes histories go back thousands of years. As a species it is super interesting... some evolved in hot-spring conditions that would simply cook most other animals. =3
https://en.wikipedia.org/wiki/Red_garra
https://www.youtube.com/watch?v=CLWkojAnyH0
Can we squint and say the gut microbiome is kind of like this?
Lol!
Because there hasn’t been enough time and the ecological niche is non existent… ?
However… upon further inspection, one could argue that the micro biome is full of beneficial micro organisms that have evolved to fill this niche…
[1] Staphylococcus epidermidis
This is one of the most abundant and beneficial bacteria on human skin. It produces antimicrobial peptides and metabolites that inhibit the growth of pathogenic bacteria.
[2] Cutibacterium acnes
Despite its association with acne, this bacterium actually plays an important role in skin health by producing propionic acid, which helps maintain skin pH and prevents overgrowth of harmful organisms.
[3] Corynebacterium species
Various corynebacteria colonize the skin and produce lipases and other enzymes that help break down sebum (skin oils) and maintain healthy skin conditions.
[4] Malassezia species
These yeasts are abundant on skin and help regulate the skin microbiome, though they can sometimes cause issues in excess.
[1] https://en.wikipedia.org/wiki/Staphylococcus_epidermidis
[2] https://en.wikipedia.org/wiki/Cutibacterium_acnes
[3] https://en.wikipedia.org/wiki/Corynebacterium
[4] https://en.wikipedia.org/wiki/Malassezia
This is very cool, and quite surprising. Cleaner fish are thought to be among the most intelligent fish because of the complexity and danger of their feeding strategy: it takes careful planning and quick thinking. But they aren't tied to any particular species of host or general tactic; naively I imagine cleaner fish are more versatile and adaptable than cone ants.
It would be interesting to learn if this occurs with other species of ants. I suppose until now nobody thought to look.
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.
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
> 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.
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"
> 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.
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
> 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.
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.
> 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.
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
> 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.
NYT story earlier on this: https://news.ycombinator.com/item?id=47754440
They crawl over them and lick and nibble their bodies? Okay I understand the quotes now.
It truly is the oldest profession.