It always boggles me how something like this evolves. Isn’t there a very long period (tens or hundreds of thousands of years) where it doesn’t look like the host termites at all? What selective pressures keep it evolving until it looks exactly like the host species?
Also why would rove beetles be better at this than others, like the army ant example? Do they just have an extra-evolutionary ability to mimic?
Evolution can happen rapidly[1]. All the needed changes could have occurred over just a few generations.
It likely starts with chemical mimicry. I can't imagine that it didn't start this way as insects live in an umwelt dominated by chemical sensory input. The beetle is able to easily visit the nest, grab food and not be attacked. Their life cycle becomes more and more intertwined with the termites until they never leave the nest. The beetles whole body starts to transform under evolutionary pressures to produce an additional tactile mimicry. That's my just-so story of how it could happen.
Just imagine the first rove beetle was adapted to be a predator of social insects. It runs to the colony and tries to grab some eggs. It's often detected and killed. So maybe by chance one beetle has a mutation that makes one of its pherhormones (or whatever) smell slightly more like termite. It's a bit less likely to get killed by the termites, so it has an advantage and higher reproductive success. The new genes spreads through the population. The another one gets a mutation that makes it's antennae just a bit more termite-like... You get the idea.
Why rove beetles? No idea, but maybe their body plan was for some reason more adaptible to change morphology? Also maybe because they were closely associated to colonial insects from the beginning as predators, and so had high selective pressure to avoid detection.
I’ve always had a notion that there’s some kind of gene theft with mimicry. The combinatorics of just rattling genes into existence that build a mock termite larva seem infeasible in the timescale involved.
What does the math look like? How many possible gene configurations are there that will build a mock termite on the back of a beetle? What’s the shortest random walk to get there from a beetle with no termite on its back and how does that compare with the total number of these beetles ever created in nature?
A single gene might have 4^300 configurations. Are there five genes or fifty or five hundred involved? How many of these beetles have ever been built? 10^20?
It needn't be perfect at first, just better than nothing (fool some of the eyes, some of the time e.g. in low-light conditions) and a gradient. See Richard Dawkins' chapter "Do good by Stealth" in River Out of Edenhttps://wikipedia.org/wiki/River_Out_of_Eden#Do_good_by_stea...
It’s not just the beetle that evolved but the termites as well. It probably started out with the termites being pretty bad at detecting their kind and becoming progressively better because of the pressure of that beetle stealing their food.
Since the discovery of DNA we build up the common knowledge that "it is all in the DNA", and the basis of evolution is a random change in DNA. It was due to a selection bias, DNA is a static structure that sits there and waits to be studied while the nano processes in a cell were impenetrable until fairly recently. DNA only contains templates for proteins. It does not contain informtion how to assemble the molecular machines from the proteins, or how "to be alive" in general. A cell is a fairly intelligent problem solver, that can adapt and chang during its lifetime, it does not need to wait for a mutation to occur. There is heritable information outside of DNA, that is epigenetic in its nature. In a multicellular organism this information is communicated and shared between cells. A beneficial DNA mutation is like a lottery win. It might be viable strategy in viruses an bacteria, who divide at an astronomical speed. A multicellular organism gametes divide only a handfull of times per generation. These need to put a more concerted effort, than a random chance, to score.
There's no incentive for termites to be good at distinguishing impostors before there are impostors. So they could get away with very bad disguise at first, then arms race started.
Totally unsupported hypothesis: They evolved first a big fat termite ass, that is much easier and it's probably good enough many times in the dark narrow alleys of a termite hive. Later they evolved the decoration. It would be nice to see how the beetle grows, because "Ontogeny recapitulates phylogeny" is not exact, but sometimes is a good approximation.
I have the same questions, more so because if it happens over a long time it’s not sustainable. The beetle population can be in some weird in-between state which could be tough for their survival.
The species co-evolved? I am assuming the early "I am a termite" mimicry wasn't very good, but neither was the termites 'not a termite' detection logic and so each incremental step of the way over 100,000+ years of evolution, they co-evolved to believe this mimicry, at a high level.
Neither party can entirely "win" in this model. At best, they get some marginal benefit in a predator/prey/host model which alters the cyclical swings of which species is higher or lower in the equipoised outcome. Over the next 1000 years, it swings the other way.
It's also worth taking the "Life/dinner principle"[0] into account. If the termites fail to detect the beetle, then they might loose a tiny bit of food or whatever. While if the beetle fails to deceive the termites it might get killed or starve. Hence the adaptive pressure is probably higher for the beetle than for the termites.
0: The name comes from the example: the rabbit runs faster than the fox, because the rabbit is running for its life, while the fox is running for its dinner.
The borders between parasitism and beneficial symbiosis can be fluent. Maybe if another parasite arises (say, some mite), it's in the beetle's interest to defend "its" termine colony against it, and it may have better ways of doing it because the mite evolved only with termites as hosts.
> The termite “puppet” may help the beetle evade detection—though termites are blind, they sense one another through touch.
Something doesn't sound about right [1]. If termites are blind why would the beetle evolve to the point it replicates the look of the termite so precisely, down to the colour? There must be another advantage, possibly when interacting with another, non-blind species.
Update: Apparently another beetle has been successfully doing the same without needing to mimic the look, but only by secreting similar chemicals [2].
Rove beetles also parasitize army ants. As soon as army ants existed these beetles we're building backdoors. Of course the ants want to recognize these cheaters and eliminate them. As ant genera diverged over time some relied more on tactile recognition of body shape ('touchers') and others not so much ('sniffers'). The parasites of touchers look like the ant but the sniffers not as much.
Off-white is not a special colour, it's typical of biological material that is neither pigmented nor unusually transparent.
So it might be simply a non-evolved default that is good enough to fool blind termites, themselves similarly off-white because they don't care about the visual appearance of their comrades.
Hey this fits my entirely unsubstantiated pet theory: evolution is not just partially Lamarckist, but there's also a purposeful mental component to it. Animals can -presumably subconsciously- partially pass on traits that they themselves think are advantageous. Eg, in this case, the beetle wants to look more like termites and so its offspring becomes more like termites as seen by the beetle even in ways that don't actually matter
I have no idea how such a mechanic may work, but there'd be a great advantage in success for animals that could develop such a style of evolution
I'm amazed that we're always only just finding out about this sort of thing... like today. the way it gets reported makes it feel like it's some sort of new innovation that the beetle just came up with, but it really impresses upon you just how much more weirdness nature must have in store for us just in our own backyard.
There really aren't that many people studying insects. Even fewer studying and cataloging plants.
Everyone assumes there's some large academic cohort of etymologists that are busy indexing and recording all natural insect life, but it's usually just some guy paying attention to one thing at a time. And sometimes there are whole families of animals or plants where there's no guy at all.
Is it possible - and bear with me, here - that we humans have something similar in our midst? Something that has co-evolved mimicry over eons to bypass our "other" triggers. No uncanny valley or creepy vibe detected. A kind of Cuckoo bird for humans.
That is an incredibly cool discovery. Another weird body hack in Northern Australia Hymenoptera is the honey pot ant. Their replete caste are passive food storage containers.
With things like extraterrestrial beings and ghosts and whatnot, we have no evidence of other examples. But mimicry like this is abundant in the animal kingdom. Who's to say that some "humans" walking among us are not just appendages of some other form of life that evolved here as well?
In fact lots of animals do, on account of there are so many ants in the world and you can benefit from [a] living in an ant colony [b] not being eaten by ants or [c] eating ants yourself and getting away with it.
I addition to coming up with an idea of the steps involved you have to consider the time this takes. You always read about some millions years, but if you stop and think about how many generations of the beetle this is and how this is a really, really long time, it makes more sense.
Coevolution in an arms race for surface/tactile mimicry.
The basic blueprint of an insect is already present in the predator.
The first of their kind may have been deformed Siamese twins.
That is absolutely astonishing, but something bothers me, I thought termites were blind and it says they are and rely on smell:
> though termites are blind, they sense one another through touch. The beetle may also absorb unique chemicals called cuticular hydrocarbons from the termites or produce similar compounds in order to enhance the perception that it is a termite as well.
So I would have expected a fake termite to be just the crudest impression but with great odour mimicry, but this visual mimicry is so incredible it suggests termites visual perception is better than we expected, or perhaps something else is going on.
And people tell me the universe is not intelligent. I think what scares us is that intelligence, like _real_ intelligence, is prior to thought and so it seems almost alien and incomprehensible to us. Yet these creatures clearly know what they are doing at some level. Just as we know what we are doing with our lungs, heart, nervous system etc. that evolved over thousands of years, but we don't know it in thought - so it eludes us as something external.
The universe indeed is not intelligent. Nor do these creatures know what they are doing. Nor did evolution know what it was doing when it created them -- evolution is not an agent or even an entity, its a description of a natural process of highly constrained brute force trial and error.
With a proper scientific and biological education these things are neither alien nor incomprehensible and the numerous conceptual errors above can be avoided.
[+] [-] doitLP|2 years ago|reply
Also why would rove beetles be better at this than others, like the army ant example? Do they just have an extra-evolutionary ability to mimic?
[+] [-] j_m_b|2 years ago|reply
It likely starts with chemical mimicry. I can't imagine that it didn't start this way as insects live in an umwelt dominated by chemical sensory input. The beetle is able to easily visit the nest, grab food and not be attacked. Their life cycle becomes more and more intertwined with the termites until they never leave the nest. The beetles whole body starts to transform under evolutionary pressures to produce an additional tactile mimicry. That's my just-so story of how it could happen.
[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7818422/
[+] [-] shellfishgene|2 years ago|reply
Why rove beetles? No idea, but maybe their body plan was for some reason more adaptible to change morphology? Also maybe because they were closely associated to colonial insects from the beginning as predators, and so had high selective pressure to avoid detection.
[+] [-] jcims|2 years ago|reply
What does the math look like? How many possible gene configurations are there that will build a mock termite on the back of a beetle? What’s the shortest random walk to get there from a beetle with no termite on its back and how does that compare with the total number of these beetles ever created in nature?
A single gene might have 4^300 configurations. Are there five genes or fifty or five hundred involved? How many of these beetles have ever been built? 10^20?
[+] [-] hyperthesis|2 years ago|reply
[+] [-] legulere|2 years ago|reply
[+] [-] mjan22640|2 years ago|reply
[+] [-] ajuc|2 years ago|reply
[+] [-] yieldcrv|2 years ago|reply
[+] [-] tomcam|2 years ago|reply
The more we learn about developmental biology the more baffling the origin of cellular behavior becomes.
[+] [-] gus_massa|2 years ago|reply
[+] [-] slavetologic|2 years ago|reply
[+] [-] yalogin|2 years ago|reply
[+] [-] melagonster|2 years ago|reply
[+] [-] phito|2 years ago|reply
[+] [-] ggm|2 years ago|reply
Neither party can entirely "win" in this model. At best, they get some marginal benefit in a predator/prey/host model which alters the cyclical swings of which species is higher or lower in the equipoised outcome. Over the next 1000 years, it swings the other way.
[+] [-] linguistics__|2 years ago|reply
0: The name comes from the example: the rabbit runs faster than the fox, because the rabbit is running for its life, while the fox is running for its dinner.
[+] [-] shellfishgene|2 years ago|reply
[+] [-] DonHopkins|2 years ago|reply
[+] [-] selcuka|2 years ago|reply
Something doesn't sound about right [1]. If termites are blind why would the beetle evolve to the point it replicates the look of the termite so precisely, down to the colour? There must be another advantage, possibly when interacting with another, non-blind species.
Update: Apparently another beetle has been successfully doing the same without needing to mimic the look, but only by secreting similar chemicals [2].
[1] Disclaimer: Layman comment
[2] https://www.newscientist.com/article/dn22526-zoologger-the-b...
[+] [-] bobbylarrybobby|2 years ago|reply
Alternatively, perhaps termites are “legally blind” but not fully sightless.
[+] [-] biomattr|2 years ago|reply
https://doi.org/10.1016/j.cub.2017.02.030
Touch is dependent on dopamine but smell not as much. And dopamine producing cells are pigmented. Could improved tactility and pigmentation be linked?
[+] [-] itsme5trange|2 years ago|reply
[+] [-] HelloNurse|2 years ago|reply
So it might be simply a non-evolved default that is good enough to fool blind termites, themselves similarly off-white because they don't care about the visual appearance of their comrades.
[+] [-] eru|2 years ago|reply
[+] [-] dan_mctree|2 years ago|reply
I have no idea how such a mechanic may work, but there'd be a great advantage in success for animals that could develop such a style of evolution
[+] [-] ravenstine|2 years ago|reply
[+] [-] zzzbra|2 years ago|reply
[+] [-] bpodgursky|2 years ago|reply
Everyone assumes there's some large academic cohort of etymologists that are busy indexing and recording all natural insect life, but it's usually just some guy paying attention to one thing at a time. And sometimes there are whole families of animals or plants where there's no guy at all.
[+] [-] rendall|2 years ago|reply
[+] [-] ryanblakeley|2 years ago|reply
[+] [-] colordrops|2 years ago|reply
[+] [-] totallywrong|2 years ago|reply
[+] [-] lproven|2 years ago|reply
As the article says, other rove beetles evolved to be fake "stealth ants".
https://en.wikipedia.org/wiki/Myrmecophily_in_Staphylinidae
They don't look much like ants to humans but they do to ants, which is what matters.
Some spiders do the same:
https://www.antwiki.org/wiki/Ant-Mimicking_Spiders
In fact lots of animals do, on account of there are so many ants in the world and you can benefit from [a] living in an ant colony [b] not being eaten by ants or [c] eating ants yourself and getting away with it.
https://en.wikipedia.org/wiki/Ant_mimicry
Even plants imitate insects:
https://www.nhm.ac.uk/discover/sneaky-orchids-manipulate-bee...
One orchid imitates an extinct bee so we only know how the bee looked from the orchid's "artist's impression".
https://whyevolutionistrue.com/2013/09/02/a-flower-hints-at-...
[+] [-] shellfishgene|2 years ago|reply
[+] [-] emadda|2 years ago|reply
Eg Beetle observes kin dying via termite melee, encodes a potential solution in the DNA for the next generation.
[+] [-] hackeraccount|2 years ago|reply
[+] [-] LeifCarrotson|2 years ago|reply
It's not realistic for beetles.
[+] [-] Borrible|2 years ago|reply
[+] [-] _a_a_a_|2 years ago|reply
> though termites are blind, they sense one another through touch. The beetle may also absorb unique chemicals called cuticular hydrocarbons from the termites or produce similar compounds in order to enhance the perception that it is a termite as well.
So I would have expected a fake termite to be just the crudest impression but with great odour mimicry, but this visual mimicry is so incredible it suggests termites visual perception is better than we expected, or perhaps something else is going on.
TL;DR something doesn't add up here
[+] [-] lproven|2 years ago|reply
It has to feel right as well as smell right.
[+] [-] edoardo-schnell|2 years ago|reply
[+] [-] Nezghul|2 years ago|reply
[+] [-] victorbjorklund|2 years ago|reply
[+] [-] ultim8k|2 years ago|reply
[+] [-] olwmc|2 years ago|reply
[+] [-] beretguy|2 years ago|reply
[+] [-] yakorevivan|2 years ago|reply
[deleted]
[+] [-] AltruisticGapHN|2 years ago|reply
[+] [-] jibal|2 years ago|reply
With a proper scientific and biological education these things are neither alien nor incomprehensible and the numerous conceptual errors above can be avoided.