There have been a number of articles that have highlighted the ongoing evolutionary development of measures and countermeasures with respect to bats and insects over the last 60+ million years.[0] Sort of a natural landscape that mirrors the ongoing battle in military developments (radar, stealth, etc).
There’s a fantastic book called “An Immense World” by Ed Yong that covers the incredible range of sensory modalities found in nature. One of the chapters goes into depth on bats and sonar.
Besides the fact that the sonar is needed for accurate ranging, as mentioned by another poster, these moths produce their sounds in response to the bat sonar, so their sounds would not be useful to find them without sonar.
As mentioned in the paper, there are also other kinds of moths which are poisonous and which do not jam the sonar, but which emit warning sounds that the bats learn to avoid.
Other moths also emit sounds, but those sounds do not prevent bats from hunting them, except perhaps for the first few times until a bat learns that those moths emitting sounds are good to eat, so their sounds do not have a jamming effect.
Bat (and human) echolocation is not based on distinguishing sonar pings in time domain, but rather listening to the frequency spectrum of the reverberating sound, ie. "measuring" the impulse response of the surroundings.
Sending a signal that resembles the echo pulses will skew the spectrum and confuse the listener.
In theory that information can be used to triangulate the "jammer" if you could measure the small difference in time from receiving in left vs. right ear but that's not how mammal brains process auditory signals.
So it's not like sonar in submarine warfare with hydrophone arrays and digital signal processing.
I could read the full paper and man they definitely talked about a few different noises the moths make and how effective each one is at deterring preying bats.
Nice garden path sentence title there: both "jams" and "bat" have several completely different meanings and it took a while until my brain permutated the right ones.
Tiger also has its own meaning, which makes the parsing even harder.
Both 'tiger moth' and 'bat sonar' are noun phrases in which the first word is not the actual meaning of the phrase. So you have two of these weird noun phrases, topped off by ambiguity about the verb ('jam' vs 'bat').
> Both 'tiger moth' and 'bat sonar' are noun phrases in which the first word is not the actual meaning of the phrase. So you have two of these weird noun phrases
That's not weird; it is the norm for English by a ridiculous margin. We do have some left-headed compounds ("pickpocket"), but they are very noticeable exceptions to an extremely strong rule.
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[0] "Sound strategies: the 65-million-year-old battle between bats and insects" https://pubmed.ncbi.nlm.nih.gov/21888517/
"Moths and bats: An evolutionary war" https://www.nhm.ac.uk/discover/evolutionary-war-between-moth...
I couldn't read the full paper but the abstract didn't mention that they were going to discuss how the jamming worked
https://www.researchgate.net/publication/26676734_Tiger_Moth...
Besides the fact that the sonar is needed for accurate ranging, as mentioned by another poster, these moths produce their sounds in response to the bat sonar, so their sounds would not be useful to find them without sonar.
As mentioned in the paper, there are also other kinds of moths which are poisonous and which do not jam the sonar, but which emit warning sounds that the bats learn to avoid.
Other moths also emit sounds, but those sounds do not prevent bats from hunting them, except perhaps for the first few times until a bat learns that those moths emitting sounds are good to eat, so their sounds do not have a jamming effect.
Sending a signal that resembles the echo pulses will skew the spectrum and confuse the listener.
In theory that information can be used to triangulate the "jammer" if you could measure the small difference in time from receiving in left vs. right ear but that's not how mammal brains process auditory signals.
So it's not like sonar in submarine warfare with hydrophone arrays and digital signal processing.
Is there any study that moth 'soft' covering is also a sound absorber, to allude bats. I didn't see it mentioned here.
[0] https://www.youtube.com/watch?v=v-s714RNXHY
[1] https://royalsocietypublishing.org/doi/10.1098/rsif.2019.069...
(Tiger moth) jams (bat sonar).
Both 'tiger moth' and 'bat sonar' are noun phrases in which the first word is not the actual meaning of the phrase. So you have two of these weird noun phrases, topped off by ambiguity about the verb ('jam' vs 'bat').
Very tricky sentence to wrap your head around!
That's not weird; it is the norm for English by a ridiculous margin. We do have some left-headed compounds ("pickpocket"), but they are very noticeable exceptions to an extremely strong rule.
https://xkcd.com/936/