g'day All
Phillip veerman & I have engaged in a little dialogue about the text
(& what they might have meant) that made this claim. Some
clarifications have been made that might be of some use to some of
you so I forward them to the list.
Cheers
Mike Tarburton
Hi Mike,
Thanks for that. It appears that I was on the right track partly
because I was wondering WHY a book would make such a statement, as in
why would a text book bother to mention what colour budgerigars are.
Even if the point is worth making, it is very poor quality research,
understanding and/or editing. There is also the aspect that
"mutations have produced a wide range of new colours" is at least in
most cases wrong as well In terms of the word "produced". Most (or
all?) the colour variants that are now established in captive
populations are not the result of producing new colours as much as
loss of the ability to make the standard colours. So blue birds are
blue not because of a new gene producing blue but due to the loss of
the ability to make yellow pigment, so that the parts that normally
show as green now show as blue, the genes to produce the blue
structural colour were always there. Likewise yellow birds are yellow
not because of a new gene producing yellow but due to the loss of the
ability to make blue structural colour, so that the parts that
normally show as green now show as yellow, the genes to produce the
yellow were always there. These are the most basic features, there
are many other variants further enhancing those two.
This principle comes in potentially useful in regard to a wild bird
of any species that has colouration different from the normal. Of
course hybridisation is another quite different source of oddities.
Maybe this extra comment could go to the B-A list to fill in the
story. That is up to you, as in you first put it on.
Philip
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