why the same melanizers that make an E bird all black does not work on E>R birchen?
Maybe the same is required, but perhaps more (others) are required to make an E^R all black.
From:
http://www.edelras.nl/chickengenetics/mutations1.html#gen_mut_elocus •E (Extended Black) –black/cream day-old chicks, adults predominantly black, but may have some pheomelanin (silver or gold) areas in hackles.
•ER (Birchen)- black/cream day-old chicks, adults predominantly black, but may have more pheomelanin (silver or gold) areas in hackles, wing bows, etc.
I believe it to be true E/E blacks \"may have some\" silver/gold in their hackles, but E^R/E^R blacks \"may have more\".
It seems the black cockerels that developed gold/silver in their hackles as they matured were the slate legged birds. I believe that although I (we) tried to develop blacks based on E, E^R has also been involved and the slate legged blacks are E^R/E^R. Australops were used to develop the blacks and they are supposed to be E/E.
My guess is that
if E produces a more solid black bird then lavender, which dilutes black and red, on E/E would produce a more even colored bird. Lavender males often turn yellowish as they mature, especially in the hackle area. If the bird carries gold (red) it may show more on a E^R bird and be diluted to that yellowish, buff, straw color. Males that carry silver (as you would agree) are better suited, but I think a bird that doesn\'t let any gold/silver leak (to be diluted by lavender) would be a more even colored bird.
It\'s just my thoughts and I hope it makes some sense.