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Re: Flying Along a Logarithmic Spiral



At 20:56 12/21/00 -0500, you wrote:
When I was doing some piloting many years ago, I learned that when another
plane stays at the same point in ones field of view, it is time to change
course to avoid collision.

Might not the robin have inherited that same lesson, but failed to notice
that the spiral can also be a collision course?

Clarence P. Bennett

What a capital suggestion!
moreover, it's testable....

You may recall that the aptly named bird migration researcher - Stephan
Vogel,(if memory serves) whose experimental setup was featured on a
long gone SciAm cover, used an inkpad birdcage floor, and a paper
carpet around its perimeter.

The subjects (American Robins) were placed in a planetarium to test
the hypothesis that they were programmed for a particular night
sky picture perhaps in conjunction with the geomagnetic field orientation
as a trigger for the annual migration.
The robins hopped repeatedly in the direction of the desired migration,
as their footprints attested.

Now if Clarence were to substitute a panoramic movie of a circling attack
or a predator stoop for the planetarium show, some measure of bird alarm
could
surely be monitored....


brian whatcott <inet@intellisys.net> Altus OK
Eureka!