What is the function of the sensory pit of a pit viper?

Answer 1

The sensory pit is a thermoreceptor. That is, it is sensitive to temperature. In the specific case of the pit organ, it actually detects infrared radiation, which corresponds to heat.

Answer 2

Sensory Pit

Answer 3

The pit vipers have developed special organs of heat reception that help them to sense warm-blooded animals, an ability that is especially useful at night, when many of them hunt. These organs consist of pits, for which the group is named, located just behind the nostrils and covered with a temperature-sensitive membrane. Some pit vipers may also use these organs to find cool refuges from inhospitable daytime temperatures.

The pit has a thermoreceptor function and is sensitive to infrared radiation; it is capable of responding to changes in temperature of only fractions of a degree. Thus pit vipers can detect the presence of animals with body temperatures only slightly different from that of the environment. In experiments where the eyes, nose, tongue, and taste-sensitive Jacobson's organ were put out of order, some pit vipers still responded to warm or cold objects placed in front of them.