Spoonerisms: Self-Tinting Dipity

This morning, I was looking at Dipity lolling around in one of her bizarre positions in the electric lap, and I started wondering. As happens with all cats with the Siamese phenotype, she has been getting progressively darker, particularly on her back, as she's gotten a little older. The Siamese "point" pattern is caused by a mutation in the gene for tyrosinase, causing it to break down at higher body temperatures and thus preventing the proper manufacture of the melanin pigment. So, now I'm wondering if she likes to lie on her back in the electric lap because she's trying to lighten her fur....



... Or maybe she just has a cold back, which is why the fur is getting so dark in the first place.