At 07:09 PM 10/1/02 +0200, Runnel wrote:
>I have
>practiced passive recording - put the mic in the grass (where some
>grasshoppers are around) and waited. Once there was a strange
>grasshopper who (which?) couldn't resist chewing the foam cover of
>the microphone. The loud sound :) of its mouthparts ruined the
>recording. I tried to chase away this guy, but it returned again and
>again. What a good-tasting foam it must be...
>
>
>Veljo Runnel
Two points:
1. Hi, Veljo, did you call that foaming at the mouth?
2. Early studies of simple insect hearing (Tufts U, K. Roeder, R.S Payne,
J. Wallman, etc.) concentrated on Noctuidae moths that avoid being eaten by=
bats using, if I remember, only four nerve cells, two on the left and two
on the right. On each side one cell was sensitive and one much less
so. When a distant bat cry was heard, the moth steered away from the
louder side. When a loud call on one side was sensed, the moth took
immediate evasive action, diving or freezing the wingbeats to mask its echo=
target profile. My point: insects certainly HEAR way above 22 kHz! This
is easy to demo this time of year in my garden at twilight - jangle a bunch=
of keys and a moth reacts most immediately. Impress your kids.
cheers,
Marty Michener
MIST Software Associates
PO Box 269, Hollis, NH 03049
coming soon : EnjoyBirds - software that migrates with you.
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