By Beth Harris, Science and Technology Editor
Beth Harris investigates novel sound production in ermine moths.
Moths are common predators of insectivorous bats. Whilst it is known that ermine moths have a variety of adaptations to defend themselves from bats, which detect prey by means of echolocation, sound production has never before been observed in this genus.
The team was comprised of researchers from the University of Bristol’s Biological Sciences department and the Natural History Museum, London. It was discovered that a small group of British deaf moths, the small ermine moths, make a continuous clicking sound in flight to serve as a warning to approaching bats. This is a direct contrast to many other species of moth which only produce sound in response to the detection of a bat.
Insects commonly use colour as a conspicuous visual signal to warn predators of their distastefulness or toxicity. However, bats hunt at night therefore colour would not provide a useful cue. Subsequently, moths have evolved to warn bats acoustically. The team propose that the ermine moths are acoustically mimicking toxic sound producing moths, such as tiger moths, to warn bats of their unpalatability and protect themselves from predation.
Sound is produced by structures called tymbals. Whilst in the majority of moths, the tymbals are connected to muscle and sound is produced as a result of muscle contraction, in ermine moths sound production in the tymbals is initiated by wingbeat.
Future work will focus on the exact mechanism by which sound is produced in the tymbals of ermine
moths.
Featured Image:Timo Vijn/ Unsplash
Want to see more Bristol research like this? Let us know your thoughts!
