but....Like with silver and gold in feathers, the male can carry both silver and gold, where a female is one or the other, could egg genes not work in the similiar fashion?
Sex linked genes work in exactly that manner. With gold & silver, because they're on the Z chromosome, the male inherits whatever allele the mother has & whatever allele the father has. He inherits them equally. The female offspring can only inherit her Z chromosome genes from her father. All other genes (autosomal) she will inherot equally from both parents. So a silver male on a gold female gives male offspring which have inherited a silver gene from the father & a gold gene from the mother.....but because silver is incompletely dominant (& often further bleached by he action of columbian) the males appear mostly silver except the hackles & shoulders. And the females are only silver. The reciprocal cross gives the same result in males but the females are all gold because they can only have inherited the gold gene from the father's Z chromosome.
If all brown egg colour genes were on the Z chromosome it would work in much the same way, but they're not; only some are on the Z chromosome the rest & probably most, are autosomal.
BTW I didn't mean to imply you didn't already know how gold & silver work. I know you do, but was using it as an illustration.
Sex linked genes work in exactly that manner. With gold & silver, because they're on the Z chromosome, the male inherits whatever allele the mother has & whatever allele the father has. He inherits them equally. The female offspring can only inherit her Z chromosome genes from her father. All other genes (autosomal) she will inherot equally from both parents. So a silver male on a gold female gives male offspring which have inherited a silver gene from the father & a gold gene from the mother.....but because silver is incompletely dominant (& often further bleached by he action of columbian) the males appear mostly silver except the hackles & shoulders. And the females are only silver. The reciprocal cross gives the same result in males but the females are all gold because they can only have inherited the gold gene from the father's Z chromosome.
If all brown egg colour genes were on the Z chromosome it would work in much the same way, but they're not; only some are on the Z chromosome the rest & probably most, are autosomal.
BTW I didn't mean to imply you didn't already know how gold & silver work. I know you do, but was using it as an illustration.
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