Question on blue marans (darker blue vs lighter blue)

[goedric]

i have read where there are darker and lighter blues... and yet the cited genetics seem pretty straight forward as a single locus model.

Does anyone know the cause of this? Are there multiple black or splash alleles or are there known modifiers at other loci? Or is the variation pretty much undefined...

Just wondering.

Thx

 

[WVduckchick]

My guess is the way the blue is created. There are several combinations that make blue. I think the blue resulting from black/blue cross is usually darker than a blue from a blue/splash cross, etc.