Rich Peet wrote:
> Note that in his story he states that an individual frog can change
> his tone only about 250 to 300 cycles.
>
> I think I have posted this sound bite before but note that this group
> of Eastern Narrowmouth Toads of Texas seem to have each individual
> calling at a different frequency. I would suspect that this does not
> equal the size of the different toads. Work for someone else to play
> with.
>
> How each of these toads decide their pitch would be interesting to
> also determine. I noted my local treefrogs also have different
> pitches for each individual but would need to pull out a group of
> examples if someone has interest in more pitch changing frogs and
> toads. I suspect it is not rare within 750 cycles. From a non-
> research type guy.
The greenhouse frog down here has a variability much greater than that.
Check the sonogram and call here:
http://wwknapp.home.mindspring.com/docs/greenhouse.frog.html
The eastern narrowmouth toad is much less variable.
http://wwknapp.home.mindspring.com/docs/eastern.narrowmouth.toad.html
Most frogs have some variation in frequency from individual to
individual. And individual calls may contain considerable variation in
frequency. Take a look at the sono's of Barking Treefrogs or Green
Treefrogs, for instance:
http://wwknapp.home.mindspring.com/docs/barking.tfrog.html
http://wwknapp.home.mindspring.com/docs/green.tfrog.html
I think the point is not so much how much that it varies, but that the
Borneo frog is actively tuning his frequency to the hole's resonant
frequency.
Walt
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