[HN Gopher] Scientists discover "cleaner ants" that groom giant ...
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Scientists discover "cleaner ants" that groom giant ants in Arizona
desert
Author : t-3
Score : 65 points
Date : 2026-04-15 19:46 UTC (3 days ago)
(HTM) web link (www.sciencedaily.com)
(TXT) w3m dump (www.sciencedaily.com)
| LeCompteSftware wrote:
| 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.
| lisper wrote:
| 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.
| fsckboy wrote:
| 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 wrote:
| > 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.
| LeCompteSftware wrote:
| 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.ph
| p/cusj/blog/vi...
| https://www.nature.com/articles/s41598-025-25837-0
| lisper wrote:
| > 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.
| culi wrote:
| 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 wrote:
| > 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 wrote:
| 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 wrote:
| > 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 wrote:
| 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 wrote:
| > 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.
| awinter-py wrote:
| this is no surprise to anyone who has read dougal dixon's 'man
| after man'
| awakeasleep wrote:
| why haven't any animals adapted to this role for humans!
| encrux wrote:
| In a Sense, cats did actually. Not through direct contact, but
| by getting rid of mice and rats that infiltrate food storage.
| buildbot wrote:
| Cat's will also literally try to clean you as well!
| TeMPOraL wrote:
| How do you know they didn't? When was the last time you just
| let bugs spend time on you?
| Joel_Mckay wrote:
| There are more mites specialized to live on your eyebrows
| skin than many like to think about. =3
| EA-3167 wrote:
| 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.
| Joel_Mckay wrote:
| 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
| laidoffamazon wrote:
| Can we squint and say the gut microbiome is kind of like this?
| victorbjorklund wrote:
| Plenty of bacteria lives in your guts feeding on your food and
| generating useful by-products.
| marojejian wrote:
| NYT story earlier on this:
| https://news.ycombinator.com/item?id=47754440
| riazrizvi wrote:
| They crawl over them and lick and nibble their bodies? Okay I
| understand the quotes now.
|
| It truly is the oldest profession.
| mmooss wrote:
| 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
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