Thermoception

Thermoception or thermoreception is the sense by which an organism perceives temperatures. The details of how temperature receptors work are still being investigated. Ciliopathy is associated with decreased ability to sense heat, thus cilia may aid in the process.Transient receptor potential channels (TRP channels) are believed to play a role in many species in sensation of hot, cold, and pain. Mammals have at least two types of sensor: those that detect heat (i.e., temperatures above body temperature) and those that detect cold (i.e. temperatures below body temperature).

A particularly specialized form of thermoception is used by Crotalinae (pit viper) and Boidae (boa) snakes, which can effectively see the infrared radiation emitted by hot objects. The snakes' face has a pair of holes, or pits, lined with temperature sensors. The sensors indirectly detect infrared radiation by its heating effect on the skin inside the pit. They can work out which part of the pit is hottest, and therefore the direction of the heat source, which could be a warm-blooded prey animal. By combining information from both pits, the snake can also estimate the distance of the object.