On Wed, Dec 03, 2003 at 01:15:06PM +1100, wrote:
> "Its funny how both Pied and Black Honeyeaters are common to arid
> areas, when both birds plumage is prodominantly black and would
> attract the heat."
> Can anyone elaborate on the reason why a bird would evolve with black
> plumage in arid areas?
In still conditions black plumage can result in a signifiantly higher
incoming heat flux than white plumage. The situation can change when
wind is present and black plumage, particularly if fluffed, may be cooler.
As I understand it this because more of radiation is absorbed at the
outside of the plumage where it lost to confection.
If you want to know more try this paper:
http://www.unm.edu/~wolf/pdf/ASZ2000feathers.pdf
Andrew
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