In: Biology
(1 pt.) Two strains of rats were selected for increased or decreased pigmentation on the head and back. After 10 generations of selection, the highly inbred high pigmentation strain had a mean pigmentation rating of 3.73, and the highly inbred low pigmentation strain had a mean pigmentation rating of –2.01. The strains were crossed, and the standard deviation for pigmentation rating in the F1 and F2 generations were 0.60 and 0.87, respectively.
(a) Estimate the number of genes affecting pigmentation in these strains. _________
(b) What is the environmental variance for this trait? ___________