I would agree with Larry's thoughts on doves keeping their feet warm,
although I would not be able to describe the calculations as well as he did.
It is known that birds all have their own spacing behavior, and it is never
seen as clearly as when they are on an electric or phone line (Perhaps the
intensity of the conversations could generate heat in some phone lines...).
If Doves, swallows, or starlings spread themselves out randomly on the phone
line, we would not notice. I believe that it is only remarkable to humans
because the spacing seems so orderly. We like to put things in order, and
previously ordered things in nature appear remarkable. You can see the
spacing behavior in American robins on your lawn (in a few months) or
American Kestrels (if you keep track of them, also on phone lines, the
spacing will be much wider...several hundred yards, but still at regular
intervals) and snow geese (if you shot a photo from above a computer could
calculate (Larry can explain the calculation) a very specific space around
each one.)
Bill Calfee
207 Maple Hill Lane
Dorset, VT 05251
802-867-5739 ph & fax
http://www.billcalfee.com
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"To announce that there must be no criticism of the president, or that
we are to stand by the president right or wrong, is not only unpatriotic
and servile, but is morally treasonable to the American public."
-- Theodore Roosevelt
----- Original Message -----
From: "Larry Hills" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Thursday, February 06, 2003 9:14 PM
Subject: Boring contribution to dove dispute resolution
> I wonder whether it is the doves' lining up on wires or their attraction
> to them in the first place that sparks (sorry) the dispute in Mr.
> Gilbert's family. I have nothing to offer about the whole shoulder to
> shoulder shtick beyond some vague hand-waving about solidarity among
> birds suffering from a moderate to severe respect deficit, but I can say
> that electrical wires wouldn't make particularly satisfactory foot
> warmers.
>
> The amount of power dissipated (convertible to heat) over a length of
> wire is equal to the square of the voltage drop divided by the
> resistance of that portion of the wire. Although a very small value for
> the resistance of the wire, placed in the denominator, appears to
> promise a nice fat value for P, the warming hypothesis runs into trouble
> in the numerator: the voltage drop is smaller than the most fastidious
> person's notion of negligible. (Which is good. Were it not so,
> transporting electrical energy by means of wires would be as inefficient
> as carrying water in a sieve.) It's not the nominal voltage of the
> line, perhaps 2400 V for a garden-variety line along a birdy secondary
> road, that counts; it's the voltage decrease from one side of the bird's
> foot to the other. Not only is that value a little less than zero point
> nothing, it must be squared, leaving us with even less nothing. And we
> haven't yet considered how much heat the wire might conduct away from
> the bird's body on a cold day.
>
> I don't think we need worry about the outbreak of a heated dispute over
> the warm toes hypothesis. (Sorry, I did it again.)
>
> My immediate, and almost certainly wrong, thought was that electrical
> wires are an abundant, if minimalist, approximation of doves' ancestral
> habitat. Wires are a little like cliffs in a way, and pigeons do thrive
> on using human structures. This idea is not helpful for wire sitters
> such as swallows, though, which I suppose allies me with the
> no-better-alternative branch of the Gilbert clan.
>
> Larry Hills
> Richmond
>
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