A caterpillar-like insect hanging on a stem, minding its own business. Suddenly the tongs appeared, moving towards the creature. As soon as you touch the chunky insect, it hisses and thumps its body side to side.
The angry individual is a mature larva of the orange leaf moth (Unlike philosophingia), and his irritation is justified, as the forceps are intended to imitate a predator. In fact, it is desirable. This scene is taken from a laboratory where researchers were investigating how the larvae and pupae of this species make shockingly loud defensive sounds.
Larvae and pupae make sounds through spiracles / Larvae and pupae make sounds through spiracles
Scientists have previously documented that some moths make sounds to ward off predators during different life stages. “We became interested in this topic when we noticed that the larvae and pupae of moth species make surprisingly loud sounds when stimulated.” Shinji Sugiuraan ecologist at Kobe University and co-author of A He studies Recently published in Journal of Experimental Biology, He said in a statement. larva It is the second stage of metamorphosis in many insects, and occurs after the animal hatches from the egg and before it becomes a pupa.
To study this sound, Sugiura and his colleagues conducted experiments on yellow-leaf pupae caterpillars and pupae, where they simulated an attack, similar to a bird peck or predator bite, by touching the insects with tweezers. During the simulation, they observed the animals’ noise and body movement, as well as analyzing the involvement of their internal organs in sound production.
According to the study, most of their mature larvae and semi-pupae responded to physical contact by making noise and moving quickly. The team conducted some of their tests underwater, revealing that the animals’ respiratory openings were letting out this hiss, producing bubbles.
“Until now, sound production in pupae was thought to occur only through physical friction between body parts or against the substrate. This is the first evidence demonstrating the mechanism of sound production in forced-air-driven pupae,” Sugiura explained.
He added: “The larvae and pupae of this species have one pair of small openings (spiracles) on the chest and eight pairs on the abdomen. They take in air through these openings.” Popular Science. “In this species, larvae and pupae produce sounds by expelling air through specific vents like a whistle.”
Except that the noise itself doesn’t sound like a whistle. The orange-leafed pupae and vocal patterns of the pupae resemble the warning sounds of snakes.
“Because moth larvae and pupae are likely preyed upon by birds and small mammals — animals that might be attacked by snakes — we hypothesize that this moth species vocally mimics snakes’ warning signals to protect itself,” Sugiura said in the statement.
It will require further study to determine whether other groups of animals have similar mechanisms and how potential predators respond to angry noises.
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