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Re: fossil fish colouration
Dann Pigdon wrote:
This only applies to creatures that exhibit metallic colouration (fish
scales, peacock feathers, etc). In the case of the fossil fish, the scales
had been preserved in sediment so fine grained that electron microscope
images revealed the original minute striations on the scale surfaces. The
colour of light reflected by these tiny ridges repends on their distance
appart (there is a direct correlation between distance between ridges and the
wavelength of the light reflected). Hence by measuring the distance between
the minute striations it was possible to determine what colour light they
would have reflected.
Point taken. But according to a report in Earth Magazine (1998/2) there was
more to it than just this kind of colouration.
Quote from Earth Magazine "True Colors":
... Biophysicist Andrew Parker at the Australian Museum in Sidney took a
magnified look at 370ma old fish called placoderms.
... He noticed cells cells which contain microscopic structures called
diffraction gratings. These split light into ist rainbow of colors, ... , and
produce a silvery reflection.
... Much to his surprise he also found cells containing clumps of either red
or black pigment granules. By mapping the distribution of color cells of one
particularly well preserved placoderm, he came up with a color model of the
creature: red on top and silver on bottom.
Theoretically this method could be used also for fossils of dinosaurs.
But I think there's one additional problem: if dinosaurs had some kind of
"fluffy" integument covering their body, the naked skin underneath wouldn't
(IMHO) show any sign of a colour pattern (e.g. stripes). Just think of an
But there may have been some naked patches of coloured skin especially at the
head and neck which could be examined with this method.