We're all aware of the famous cobra with its threatening hood. There are 270 types of cobras that have been identified as of today. One such type is the spitting cobra! Most of us are familiar with the uniqueness of the spitting cobra. The minute we think of the spitting cobra, we picture the cobra spitting out a stream of venom. The venom sprayed by the spitting cobra is only a defense mechanism, and not meant to catch prey. However, the venom is used to kill the prey via lovely bites. Spitting cobras relish birds, lizards, carrion and other small snakes.
According to several studies, it is believed that this spitting mechanism is actually an adaptation, which protects spitting cobras, from predators larger than themselves (including man). When threatened, these cobras eject a spray of venom into the eyes of their predator, with incredible accuracy! The spray, although not fatal, causes temporary blindness, which if not treated, results in permanent blindness. Spitting cobras are intriguing reptiles. Let's have a closer look at them.
The name spitting cobra is actually misleading, causing one to think that the cobra actually spits venom. However, the underlying truth is that they are those species of cobras, that actually spray venom into the face of the predator. The venom is not ejected by puckering the lips and blowing the venom outward, instead is sprayed out in distinctive patterns, from the holes in the front of its fangs.
Spitting cobras eject venom from their fangs as a defensive response, on encountering their predators. The muscles of the venom sacs contract and force out the venom, via the holes at the tip of the fangs. The holes in the fangs are narrow and teardrop-shaped, thereby allowing a narrow stream of venom to be sprayed, at high speed. The tinier and rounder the hole, higher is the speed of sprayed venom, and better is the accuracy. It's this venom spray that makes these spitting cobras one of the most feared snakes. They can spray their venom to a distance of 6 feet and also have the ability to spray venom over 40 times in quick succession.
Why do spitting cobras spew venom?
Spitting cobras are not particularly muscular, and do not have the strength to squeeze and kill large prey. Their fangs are small and if they bite, they need to hold on to their prey for a long time, before it dies. If they bite a large predator, they will have to bite it and wait till it dies. In this struggle of holding on to larger prey, if the prey gets loose, it can kill the spitting cobra, even after injecting the venom. This is because the venom takes time to kill the predator. Thus, it is important for the spitting cobra to disable its predator, as quickly as possible. This it does by blinding it.
Research conducted by Katja Tzschätzsch, a research student at the University of Bonn in Germany, revealed that spitting cobras aim at moving faces. According to her findings, the spitting cobras made no efforts to spray venom at hand movements. They aim for the eyes and once the venom hits the eye, the neurotoxins in the venom cause a condition of chemical conjunctivitis, which eventually blinds the victim temporarily. The venom of a spitting cobra has no effect if it falls on the skin. It has to fall into the eyes, for effect, which is why the cobra aims at the eyes.
Venom is sprayed in geometric patterns...
Research conducted by Dr. Bruce Young and his colleagues, Melissa Boetig and Dr. Guido Westhoff, at University of Massachusetts Lowell, has revealed that the venom sprayed from the fangs of the spitting cobra, is not a single stream, hitting only one spot. Instead, it is sprayed in geometric; oval shapes. These shapes or patterns are produced by certain head and neck movements of the spitting cobra, just before ejecting the venom. Thus, when the cobra aims at the eye, it's actually anticipating the head movements of the victim, and sprays a jet of venom, in geometrical patterns, across a plane of probability, and not at one particular spot. The geometric oval pattern maximizes the chances of hitting the eye.
How poisonous is the venom?
Venom sprayed by spitting cobras, will not harm the skin, however, if it comes in contact with the eyes it can cause temporary or permanent blindness, along with severe pain. The venom is a neurotoxic, tissue-destroying, blood-cell-destroying venom stored in the fangs. As the venom hits the predator's eyes, the cobra gets its chance to escape. When the neurotoxic venom comes in contact with the eyes, besides causing a stinging sensation, the venom gets completely absorbed by the capillaries of the conjunctiva, in the eyes. This conduces to irritation in the cornea, followed by the tissue damage and temporary blindness. Extensive tissue damage can conduce to permanent blindness. If the venom happens to enter the bloodstream, via wounds or cuts, it may result in systemic problems.
Species of spitting cobras...
12 species of spitting cobras have been identified so far, with seven coming under the African category and five under the Asian category. Naja nigricollis, Naja nubiae, Naja pallida, Naja ashei, Naja katiensis, Naja mossambica and Naja nigricincta come under the African spitting cobra category. Naja sputatrix, Naja sumatrana, Naja philippinensis, Naja samarensis and Naja siamensis come under the Asian spitting cobra category.
World's Largest Spitting Cobra...
Ashe's spitting cobra (Naja ashei), also commonly known as the large brown spitting cobra, is the largest species of spitting cobra found in world today. Native to the African continent, this giant spitting cobra measures about 4 to 6 feet in length. However, the largest one found in Kenya, was almost 9 feet in length. Its venom is considered to be the most poisonous of all spitting cobras, and has the capacity to inject twice the amount of venom, any snake can inject in one bite. One bite has enough venom to kill 15 to 20 people.
The venom of a spitting cobra is not as venomous as the King Cobra, nevertheless, it's still quite deadly. If you are dealing with spitting cobras, make sure you have a face mask over your glasses and a full body suit on. If the venom falls on open wounds, it can prove deadly. So take all possible precautionary measures.