Pit Vipers (such as rattlesnakes) have IR sensitive pits on their noses.
Unlike how a photoreceptor works (absorption of a photon causing photochemical changes in a molecule which interacts with membrane proteins, affecting the membrane potential), the
Pit organ is like a low resolution pinhole camera, but transduction (environmental condition --> neural signal) works by affecting a temperature sensitive channel protein, affecting membrane potential. These receptors and the sensory cells they resided in, are situated, in the pit organ, so they are very temperature sensitive to heat from the environment.
There apparently other IR sensitive animals:
Vampire bats have heat sensors in their weird shaped noses.
This
also seems to work through a temperature sensitive membrane channel protein, like the pit viper, but presumably, independently derived. Both involve the
TRVP1 channel (Capsaicin receptor).
Perhaps the channel's evolutionary precursor was involved in the body's temperature sensing mechanisms.
There are
IR sensitive insects, as well as some fish:
Other organisms that have thermoreceptive organs are pythons (family
Pythonidae), some boas (family
Boidae), the
Common Vampire Bat (
Desmodus rotundus), a variety of
jewel beetles (
Melanophila acuminata),
[38] darkly pigmented butterflies (
Pachliopta aristolochiae and
https://en.wikipedia.org/w/index.php?title=Troides_rhadamantus_plateni&action=edit&redlink=1), and possibly blood-sucking bugs (
Triatoma infestans).
[39]
Some fungi like
Venturia inaequalis require near-infrared light for ejection
[40]
Although near-infrared vision (780–1000 nm) has long been deemed impossible due to noise in visual pigments,
[41] sensation of near-infrared light was reported in the common carp and in three cichlid species.
[41][42][43][44][45] Fish use NIR to capture prey
[41] and for phototactic swimming orientation.
[45] NIR sensation in fish may be relevant under poor lighting conditions during twilight
[41] and in turbid surface waters.
[45]
The IR wavelengths that transmit through the environment (air or water), will affect what biological sensors sensors can detect. There would be no selective reason to evolve sensitivity in other wavelengths. But it might exist as a by product of the detection mechanism. I don't know what specific wavelengths they detect, but there are possible approachs:
use a behavior response to signal awareness of a sensory signal.
use a neural physiological assay (sensory fiber response) when exposed to different stimuli (the nerves and sensory organs in snakes and bats are well known).
Animals can also get around in the dark using other distance sensing capabilities.
Bats have active sonar, which works very well and is very sophisticated.
Owls have a very sensitive directional hearing sense, which they can use to find mice in the dark, based in the noises the mouse makes.
In the water,
many fish are electroreceptive, but knife fish are actively electrosensitive fish which can sense their environment, detect prey, communicate with con-specifics, change frequencies they transmit at to avoid interfering with frequencies other fish. Electric eels are related to this fish.
These guys can cruise around at night or in murky waters with a very short visibility distance.
Many other fish are passively electroreceptive. They listen, but do not broadcast.
Shark, rays as well as lots of bony fish can do this.
When there is an opportunnity for an organism to gain a selective advantage by evolving a way to "see in the dark", they can opportunistically make whatever kind of a system they can cobble together from what's available (molecularly speaking). Thus, there are many solutions to the problem, but not usually capable beyond what is needed in it environment.
).