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RE: Bobbing head...
- To: "Bird (E-mail)" <carolinabirds@duke.edu>
- Subject: RE: Bobbing head...
- From: "Armstrong, Craig" <CraigArmstrong@PerformanceInc.com>
- Date: Fri, 12 Jul 2002 14:14:10 -0400
- Sender: carolinabirds-owner@acpub.duke.edu
>If you carefully watch a dove (or others that "bob") walking, you'll
>notice that what it actually does is hold its head motionless in place
>while it moves its body forward, then very rapidly snaps its head
>forward to "catch up" with its body. This way, its head remains
>motionless a much higher percentage of the time than it would if it
>simply went along for the ride. Why should this be advantageous?
>Motionless eyes can detect potential dangers far better than eyes on
>the move.
Thanks for the observation Clyde, I'll certainly spend some time looking for
that this weekend. Doesn't make sense to me though, if the head were to
move with the body then all the movement would begin and end at one time.
If the body moves and then the head snaps forward to catch up, it seems like
two separate movements which means movement over a longer period of time.
More time moving would mean a higher likelihood of being spotted, at least
that's what it seems like to me??
>although the head is moving relative to the body, it is stationary relative
to its
>surroundings. At this point, the eyes are steady, and the bird can pick out
tiny morsels
>of food or distant predators.
I just received Leah's post while replying to the previous one. That sheds
a little more light on it, guess now it's time to go watch the Doves.
Thanks again all, have a great weekend!
Craig Armstrong / Chapel Hill