as small as a world and as large as alone, [Image description: A pinkish-red moth on a black...

8:04am June 17, 2015

[Image description: A pinkish-red moth on a black background.]

On Wikipedia, this photo had the intriguing caption of “The moth Bertholdia trigona is the only animal in nature known to jam the echolocation of its predator.”

I looked up more information, and found this story on NPR: “Moths Outwit Bats by Jamming Sonar”.

Note that the story contains a brief description of removing parts of sensory organs from insects For Science, and therefore could be disturbing. (1)

Here’s the story with that aspect of the article removed, specifically so you can read it without having to read the specifics of insect mutilation:

Bats are among nature’s cleverest predators, using ultrasonic signals to locate their prey at night. They make pretty quick work of moths, one of their favorite meals.
However, one species of tiger moth that lives in the southwestern U.S. apparently has learned to outfox the bats by jamming their signals.
Easy Prey
In the bat-eat-moth world of the summer night, moths are at a distinct disadvantage. Bats can locate and snap a moth out of midair with the greatest of ease. They use what biologists regard as one of the animal world’s most efficient tools of prey: ultrasonic signals that work like sonar.
But Aaron Corcoran, a graduate student at Wake Forest University, was intrigued by a species of moth that also makes ultrasonic sounds. He wondered if this was some kind of bat deterrent. The moth, a 1- to 2-inch-long orange species called Bertholdia trigona, has organs on its body called “tymbals.”
Some Moths Use Sound To Fight Back
“A tymbal works like a pop can,” Corcaran says. “If you push in on the side of a pop can, it will make a click, and when it releases out it makes another click. We’ve measured up to 450 clicks in a tenth of a second. That’s a tremendous amount of sound that this moth is making.”
[excised potentially disturbing content]
As a bat is flying around, it is constantly making chirps and listening for the echoes, Corcoran says. “And as it closes in on the insect, it increases the repetition rate with which it is making those sounds.” The chirps stop when the bat snares the moth.
[excised potentially disturbing content]
‘The Bat Gave Up’
Corcoran decided to try the experiment using an intact moth with its tymbals clicking away as the bat closes in.
“You hear the bat going through its normal progression and starting to speed up,” Corcoran says. “Then the moth turns on its sound production, which sounds almost like a siren because the pitch is going up and down. At that point, the bat does something very abnormal: It starts slowing down its repetition rate, the opposite of what it normally would be doing. As soon as the moth’s rattle-like sound started, the bat got confused and missed the moth. This kept happening, over and over, until the bat gave up and crawled back to its cage.”
Corcoran, who published his findings in the journal Science, ran the experiment several times with the same results.
He has ruled out the idea that the sound just startles bats, as the bats would have grown used to that and eventually would have had more success. Corcoran and his colleagues think the moths are using some kind of ultrasonic jamming.
“What appears most likely is that the clicks are interfering with the bats’ neural processing of the echoes that are coming back,” Corcoran says.
If you live in the southwestern U.S., you just might catch some of this aerial action underneath a streetlight at night.

Footnotes under cut, dealing with the mutilation For Science! thing in both other animals and humans.

(1) It reminds me vaguely of when my father and I discovered the work his cousin did – his cousin had been a huge bully to him and other kids when they were growing up, and had gotten a career in science that just so happened to allow him to hurt animals with impunity. Not that I think that’s what’s happening here. What’s happening here seems to be the much more common phenomenon of people forgetting that other living creatures are in fact other living creatures, and that our desire to understand them doesn’t trump their right not to have body parts mutilated so we can see how they work.

Oh and please don’t respond with anything along the lines of “If this were done to humans, we’d shut it down immediately.” In my country alone, the USA, there’s a long history of using developmentally disabled children in similar experiments, as well as children with severe physical illnesses who have to spend long periods of time in the hospital – I know someone who described living in a hospital as a child, where experiments were performed on her and other kids without even getting parental consent. If the kid lived, then the experiment might be disclosed as “This new, experimental treatment saved your child.” If the kid died, it would be blamed on their disease, not on the experiments being done on them. The children, of course, lived in constant terror, but were not allowed to communicate this.

That may seem like a tangent, but just to say, the reason I’m so sensitive to seeing things like this done to other species, is because I’m demographically one of the people this could have easily happened to if I was in the wrong place at the wrong time growing up. And some of my friends were not so lucky. So yeah – I think it’s great that we’re learning about the one animal that can jam bats’ echolocation, but cutting them up isn’t the way to do it. So read with caution, even if this is fascinating stuff. (No, read with even more caution because this is fascinating stuff, and people are far more likely to excuse this stuff in the name of fascination or “For Science!” than they would be if they just heard about someone doing it at random.