In guinea pigs, black (B) is dominant to brown (b), and dolid color (S) is dominant to spotted (s). A heterozygous black, solid-colored pig is mated with a brown, spotted pig. The total offspring for several litters are black solid=16, black spotted=5, brown solid=5, and brown spotted=14.
Are these genes linked or unlinked? If they are linked, how many map units are they apart?