I think [COLOR=333333]moomoodiddy is referring to the double dose effect of the barring gene, making the males who carry two copies lighter. As far as i know two copies dilutes both eumelanin and pheomelanin leading to a lighter male carrying two copies. [/COLOR] [COLOR=333333]The best barring needs slow feathering, like the plymouth rock. (i have heard people also saying a single copy of Co helps, not sure about that though) [/COLOR] [COLOR=333333]Cuckoo then, as a phenotype, would be barring with fast feathering, Barred would be barring with slow feathering. [/COLOR] [COLOR=333333]i suppose crossing out to black would sex link the offspring, and given that the male would carry one copy would have darker/ more distinct barring then a male carrying two copies. [/COLOR]