In horses, the gene for black coat color is dominant over the gene for brown coat color. The gene for long manes is dominant over the gene for short manes. After a cross is made between a homozygous black, long mane mare (BBLL)and a stallion homozygous for brown color and short mane (bbll), and the F1 offspring are interbred, the expected outcome in the F2 for a brown, long mane horse would be

3/16

Explanation:

Given,

Black coat color is dominant over brown coat color.

Long mane is dominant over short mane.

BBLL X bbll =

F1: BbLl = Entire progeny has black color and long mane

BbLl progeny will produce BL, Bl, bL and bl gametes. When they interbreed, the resultant F2 progeny will be in 9:3:3:1 dihybrid ratio. Hence in F2,

BBLL : BbLL : bbLl : bbll = 9 : 3 : 3 : 1

3/16 progeny will have bbLl genotype hence 3/16 progeny will have brown, long mane.