I recently adopted a beautiful two-year-old from Boxer Rescue LA. He appears to be black with the usual white markings and has the personality and behavior of a boxer. I read that a totally black boxer is a genetic impossibility but the boxer rescue people said they do exist. I cannot find any stripes to indicate a reverse brindle. I wonder what cross would produce this color if he is a mix. Whatever the case, he is a wonderful dog, but I am curious.Any ideas out there?