The dogbane tiger moth, Cycnia tenera, mates at dawn.
The female initiates courtship by releasing a female sex attractant. The
male approaches from downwind. When the male arrives in the vicinity of
the female he does two things. He produces high frequency (50 kHz) clicks
using tymbal organs on his thorax. When you view the video you should be
able to hear the clicks because we have lowered their frequency into the
range audible to humans. The male also releases a pheromone from tiny inflatable
scent- disseminating structures called coremata. This happens too quickly
for you to see it in the video clip. The acoustic and chemical signals
appear to be redundant i.e. either is sufficient to stimulate the female
to mate. When we operate on males and prevent them from producing sound
or releasing their pheromone the female does not accept the male and often
leaves (Conner, 1987).
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