loose thin skin with very little fur. She has almost no hair on her belly and chest, thin hair on her sides, and normal hair down her back.
In my opinion, this is it right here. Loose THIN skin coupled with long lean muscle. Thin skin means that the capillaries that carry the blood are close to the surface where they are more efficient with heat exchange. The loose skin means that there is more surface area to hold these capillaries. It's a four core radiator over a three. Both black dogs have a very light hair coat, allowing the skin to have full access to the ambient air temperature which is typically a few degrees lower than a dog's standard operating temperature. The long lean muscle requires less oxygen to feed than does a thick bunchy type.
Just my opinion derived from comparing the anatomy of these dogs to other critters designed for desert climates.
CHeers
M
