[Cryptography] Applied Steganography: Do Moths Do CDMA-based Communication/Navigation?

[Kent Borg]

[There is probably literature on this but wild speculation can be fun.]

I think chaotic moth flight is not so dissimilar to purposive bee 
flight. A bee will follow a predicable zig-zag, mapping the edge of 
plume of perfume from an upwind flower. I think these moths are doing 
something similar, but modulated by a PRNG function. As with CDMA radio, 
these bugs are communicating with each other, they want to find each 
other, they are using plumes of pheromones to communicate, but with this 
extra chaotic signal mixed in, so as with CDMA radio communications, 
they need to sync up with each other, and they do seem to do so: there 
will be several in an area, and then there will be none, and awhile 
later several again.

The other day at work I saw one parked on the office window: I looked 
closely, and it had big comb-like antennae. Looked like high-gain rigs, 
to quickly measure presence and absence of interesting molecules, as it 
rapidly darts about in flight.

These moths seem to function well when presented with solid objects, 
they and the plumes can't go through solid objects, and they don't bang 
into them. But when confronted with a screen covering an open window, 
they get messed up, they get stuck, their PRNG modulated plume following 
algorithm says to go that way but they can't. They look like they are 
trying to get in the house, but I think the screen has simply exposed a 
weakness in their strategy.

The birds have noticed, they are now hunting up against the kitchen 
window and storm door, I occasionally hear them bang into the wall or 
door as they go in for a snatch--each time I hope they got it. There is 
bird shit under the roof, on a table that normally never gets any. And I 
am pleased.

Trying to drag this a /bit/ on topic, if these bugs are navigating the 
world in a sensible (if effectively slow) manner, mapped through a PRNG 
modulation, it needs to be pretty simple. Not just to generate, but more 
so to demodulate it, so these simple creatures can accomplish their 
larger navigation goals, and really impressively, agree with other moths 
on compatible modulation phases. They get to use dedicated circuitry, 
but they still do this in such a way that vastly more intelligent birds 
can't decode it, and instead have to prey in places where the moth's 
design breaks down. Like up against my kitchen wall.

Disclaimer: Long ago I read in Scientific American (or was it Science 
News?) that butterflies, flighty as they are, do follow scent plumes to 
seek food. So I am not being that original.

My possible insight would be that they don't do this to find stationary 
food (I don't know that they even can eat in this stage of their lives), 
rather they do this to find similarly moving mates. (Probably same-sex, 
too. A CDMA-modulated cloud of one gender probably attracts the other 
gender better than a lone chaotic moth could.) They need to be 
predictable (enough) to each other, but still random to predators. Can 
they really adjust their PRNGs to correlate and roughly group 
themselves? How the heck do they do that?


I am impressed that these bugs show no caution as I try to kill them, as 
though they are on suicide missions, or maybe they feel invulnerable 
cloaked behind their stego navigation.


-kb, the interdisciplinary Kent who can mix casual nature watching with 
kinda up-to-date radio communications and cryptography.

P.S. As the afternoon goes on the birds are banging into the house more 
gently. I think they are perfecting their technique. Smart birds. I left 
a fan on out there, I was sitting in front of it earlier. I think that 
is further messing with the moths' design and helping the birds.
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