Study: Virgin Male Moths Show Their Inexperience when Chasing Females
As with any species, there is a learning curve when trying to attract the opposite sex. Genetic knowledge can only go so far in preparing a young male. The rest is learned through trial and error, usually many errors. Moths are no different. When the female emits her pheromones to attract a mate, the male gets crazy and rushes headlong into a mating dance with her. This consists of a long flight in which the male tries to catch the female. What the virgin male does not know is that a moth's flying muscles must be adequately warmed up before engaging in a prolonged powerful flight. Their inexperience tends to cost them the contest for the female to the more experienced males.
The study was conducted by researchers Prof. Franz Goller, Prof. Neil Vickers and doctoral student, Jose Crespo of the University of Utah. It involved observing the Helicoverpa zea, aka the corn ear worm, part of the largest and most commonly seen family of moths and butterflies. The study centered around how the moths interacted with various odors, their primary means of communication.
"Finding out how odors switch on behavior is critical to the whole picture," Vickers says. "Furthermore, because insects have this amazing ability to fly, which not many animals have, finding out how flight is turned on by odor is an issue relevant to many insects... There is a whole constellation of behaviors driven by odor, and this is true of all manner of insects" and even other animals and people.
Until now, researchers thought the moths simply warmed up as fast as they can. "These guys don't all heat up at the same rate," Vickers says. "The guys exposed to the pheromone odor, go 'Wow!' and they warm up faster and take off more quickly. And that compromises the flight power they can produce."
The female pheromone is typically detected by several male moths who all compete to get to the female first. It is natural instinct to take off for flight as fast as possible.
However, with moths, the flight muscles are perhaps the most metabolically costly in all of the animal kingdom. Flight requires the use of lots of oxygen and power. It can be very taxing on the body.
Taking off for a long chase before fully warming up the muscles can be physically damaging, causing the male moths to slow down and eventually drop out. Meanwhile the experienced moth will bide his time, watching with great amusement as the young males tire themselves out, then go get their prize.
This study has been published in the Journal of Experimental Biology.
Link to youtube video of a moth warming up: http://www.youtube.com/watch?v=g1pXzlyIk8s
Moth image via Shutterstock