FAQ: why are you using different genetic symbols / formulas in your book than in mammals (humans)? Did you invent it?
Answer: No, but I wish I did (LOL). In birds they developed their own genetic system during the years, but it was the English animal geneticist Professor Francis Crew who introduced it in his book: ‘The genetics of budgerigar’ (1935). He was a pioneer in his field leading to the University of Edinburgh’s place as a world leader in the science of animal genetics.
Later, all other authors also used this system in their books. So, it became in most aviculture clubs the standard. Of course, during the years, the system has been expanded with new symbols and adapted where necessary by several authors. But it is always the same basic. So, it was self-explanatory for me that I used this system in my book.
Crew, F. A. E., & Lamy, R. (1935). The genetics of the budgerigar.