Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: feather color

Leigh Palmer wrote:

The mallard colors (and those of hummingbirds, morpho butterflies,
etc.) which are angle dependent are interference colors.

Do you mean interference such as that observed in thin films such as
soap bubbles? If so then there must be some transparent material
covering the wings. Is this the case?

Here in Canada
we have a patch on most of our bank notes which exhibits the same
phenomenon, but over a wider range of colors. Depending on the
illumination and viewing angles, the patch can go from yellow to
blue violet. The special quality of these colors derives from the
fact that they are nearly spectral,

What do you mean by nearly spectral?

and also they often look
to be different to each of the two eyes.

Interesting... I imagine any brain that could be told that an object
is emitting red light as well as green light and somehow decide to
call that object yellow would have a field day with different
information coming to each eye from the same spot .

The former property is
called "iridescence", and the latter "chatoyance". The etymologies
of these words are interesting, too!

Nice try, but it is too late for me to be looking up such things.
However if you are inclined to make things easy on me I would be
interested to hear more about these interesting etymologies.


--
Cliff Parker

Never express yourself more clearly than you can think. -- Niels
Bohr