From an evolutionary standpoint, these facial pits underwent a parallel evolution although, for various reasons, did evolve in slightly different positions on the face. What is interesting about this sensory organ, is that it evolved in two very different classes of snakes the pythons and boas which are referred to as being primitive snakes and the pit vipers which are considered more advanced, due to the presence of venom which is used to kill prey. However, it was not until 1957 when Bullock and Fox showed them to be perceptive to infrared radiation, that we fully understood their purpose. Why pythons and boas have more pit structures than pit vipers, is difficult to reason, but is possibly due to them being less sophisticated, and having more makes up for this discrepancy.įirst described by Desmoulins in 1824, he observed that these pits were rich in nerve endings and attributed them to some sort of sensory function. In pit vipers, a single pit between the nostrils and eyes is present. These snakes supplement the use of pheromones and visual perception with that of heat detection.īoth groups of snakes employ the services of special sensory structures called heat pits which, in pythons and boas, resemble ‘holes’ located in the upper, and sometimes lower labial scales (essentially the upper and lower lips) of which there may be up to 13 pairs present. Well, that is just how the pythons and boas (Pythonidae and Boidae) and the New World vipers, Crotalidae – or more commonly referred to as Pit vipers, can see the world. And the more heat you give off, the brighter the image. But imagine supplementing your senses with the ability to see the world around you as a thermal heat source, where other animals can be detected according to their body heat. The detection mechanism of prey within the snake families is predominantly achieved through the use of the tongue (via pheromones), and eyes (visually) this is a pretty standard organization, irrespective of the species or family.
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |