brown. If at least one says black, the black pigment dominates in visible appearance. That’s why two black-looking dogs can sometimes produce a brown puppy.
- How two black parents can have a brown puppy
This is the part that makes most people blink. If both parents carry one black allele and one brown allele, each puppy has four possible genetic combinations: black/black, black/brown, brown/black, or brown/brown. In practical terms, that works out to about a 25% chance of brown, a 50% chance of black while carrying brown, and a 25% chance of black without carrying brown.
That 25% figure is per puppy, not per litter. A six-puppy litter does not guarantee one and a half brown puppies, of course. Real litters are a roll of the genetic dice each time. You could get zero brown puppies in six, one brown puppy in six, or more than
