This are pigment cells which are directed by hormones!
>
> 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
>
> ***
>
> <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
>
> ***
>
>
Best regards
Harro Hieronimus, Solingen, Germany
harro.hieronimus at t-online.de
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No fish - no fun
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