Bats contain brown fat between their shoulder blades. how could this brown fat be an adaptation to torpor?

Mitochondria in brown fat have the ability to produce heat without the need to produce ATP molecules .

Explanation:

Hibernating bats develop brown fat on their backs between the shoulder blades, but mammals can also store brown fat in their bellies and other parts of their bodies .

This characteristic that bats and other animals that hibernate possess gives you the possibility of producing energy without the production of ATP through cellular mitochondria.

That is to say, the brown adipose tissue - the main heat-generating organ in the body and is activated with the cold - is also an endocrine organ that secretes signaling factors that activate the metabolism of fats and carbohydrates. The brown adipose tissue helps "burn more calories" and produce body heat from fat.

b is dominant over the allele for the white fur.