Hello,
I have also noticed this quick color change phenomena
and wonder as to its physiology cause. Blushing comes to
mind, which is due to a change in peripheral circulation,
but is always of the same coloration.
I have some Boesmany and the vertical dark stripes that
separate the front and back fish colors sometimes flash
sequentially like a marquis neon sign.
Maybe like the in the class of lepidoptera, or moths and
butterflies, where the wings are covered with very small
wedges wich are separated by lengths comparable to the
wavelength of light; diffraction and interference of light
changes colors according to illumination and viewing
directions.
Regards Ed Romana
erom at earthlink.net,erom
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<snip> I noticed my some of my praecox sometimes light a
>yellow stripe along their back. They can light this on
>and off quickly <snip>
>
>Best regards,
>Hugo Hoekstra
***