Editing Thermoception (section)

=== In snakes ===
{{main|Infrared sensing in snakes}}
[[Crotalinae]] (pit viper) and [[Boidae]] (boa) snakes can effectively see the infrared radiation emitted by hot objects.<ref>{{cite journal | vauthors = Newman EA, Hartline PH | title = The infrared "vision" of snakes | journal = Scientific American | date = March 1982 | volume = 246 | issue = 3 | pages = 116–127 | doi = 10.1038/scientificamerican0382-116 | jstor = 24966551 | bibcode = 1982SciAm.246c.116N }}</ref> 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.