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Comment by selcuka | Hacker News Reader

> 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].

[1] Disclaimer: Layman comment

[2] https://www.newscientist.com/article/dn22526-zoologger-the-b...

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Perhaps blending in with termites helps it avoid being eaten by predators of termites to whom it would stand out.

Alternatively, perhaps termites are “legally blind” but not fully sightless.

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.

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?

Maybe the beetles don't know that the termites are blind?

The termites evolved that coloration for a reason, perhaps to avoid predators. It stands to reason that the beetle would also evolve avoid predators in the same way. That is, the mimic has two audiences: the termites, and the termites' predators.

Not necessarily, if the color doesn't matter it would evolve towards the one that is the least costly. Probably like not pigment at all.

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.

The colour replication might be a co-incidence?

Or alternatively, those colors are good for a beetle with a termite on its back for the same reason they're good for a termite. They help whatever the termite looks like blend in to the area where termites usually are.

Or a result of diet.

The beetle itself has a different colour than the puppet, though.

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

Perhaps there's some other advantage to the termite puppet other than food stealing?

Maybe sexual. Other beetles think it's really attractive to mimicry termites.

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