*pats askbox gently* there are more Thermoreceptors?
(I'm sorry ur dome was so hot; I hope its much cooler now!)
My bluff has been called! Hooray!!
I am not a neurologist, a biologist, or a scientist. If anyone with better credentials than "obsessed with emergent properties" contradicts me, listen to them instead.
Cell membranes include little portal proteins that open under certain circumstances based on the shape of the protein and let chemicals into and out of the cell. These portals are useful for all sorts of things: managing water and nutrients, sending messages to nearby cells, serving the whims of tiny intercellular cats. Science hasn't found the tiny intercellular cats yet, but we all know they're there; the existence of a door that can be opened necessarily implies an indecisive feline.
Some protein shapes open up if the temperature is within a certain range. This means that if a cell with that sort of protein in its membrane experiences a temperature in the right range, it will move some chemicals around. This is used to make nerve cells that send a message towards the brain whenever they experience a certain temperature.