What good is it going to do the snake if the rat dies later?"īecause of this vulnerability, cobras have developed an elaborate system of bluffing to intimidate anything they see as a threat. Even a rat, if the cobra doesn't disable it immediately, could turn around, bite, and kill the snake. "And there's a big risk to the snake in closing in on prey. "It's not the best venom-delivery system," Altimari said. To kill their prey, they need to bite and hang on. But cobras are not particularly muscular, and their fangs are relatively small. Non-venomous snakes like boas and pythons grab their prey and squeeze them to death. "The snake will spit at something bigger than it, and feast on something smaller," said Ferri, who is the chairperson for the American Zoo and Aquarium Association's group that advises on the scientific classification of snakes. Why spit instead of bite? Spitting is strictly for defense, the experts say. The venom hits the floor of the fang hole, bounces upward and out," Altimari said. "When the snake contracts its venom gland, it squeezes a small amount out at high pressure. Those that can have a specially modified fang with a small hole in it. The lesson is clear: If ever you're confronted by a spitting cobra (common in Africa and Asia) stand back at least 10 feet (3 meters) and protect your eyes. In the worst case these burns can lead to blindness. The sensitive cornea reacts with severe stinging pain. What happens if a cobra's venom lands in your eye? The cocktail of toxins consists of nerve poisons and other components harmful to tissue. The Mozambique cobras hit their target every time. The evaluation of the traces of venom on the photos and the visor revealed how accurate the both species' aim is: The black-necked spitting cobras hit at least one eye eight out of ten times. Only two cobras reacted to photos of faces. "Movements involving the hand elicited no response from any of the snakes." "The snakes really do spit only at moving faces," was her first finding. She recorded the spitting process using a high-speed video camera. In her experiments she either stood face-to-face with them-protected by a plastic visor-or she used photos. Katja Tzschätzsch used four red Mozambique and six black-necked spitting cobras. "It was necessary to actually show this in order to ask the next question: How do cobras identify the eyes in different animals and humans?" said Guido Westhoff, the professor at the University of Bonn who supervised Tzschätzsch's work. If everyone knows spitting cobras aim for the eyes, why ask the question? "Anyone at the zoo working with this type of snake wears a face mask because that's usually where they aim," added Dino Ferri, assistant curator for reptiles and amphibians at the Audubon Zoo in New Orleans. "These animals always aim for keepers' goggles," he said. Sam Lee, assistant supervisor in the Bronx Zoo's department of herpetology, concurs, again based on personal experience. Our keepers at the Philadelphia Zoo always wore face masks." My experience has been that the red spitter and the black-neck went right for your eyes. "But I'd be surprised if anyone in the field thinks otherwise. It's mostly been anecdotal evidence," said Bill Altimari, a herpetologist at the Arizona-Sonora Desert Museum. "To my knowledge there hasn't been a lot of work done on whether they actually aim for the eyes. The lab results don't surprise snake experts. Katja Tzschätzsch, a research student at the University of Bonn in Germany, has demonstrated that the red Mozambique spitting cobra and the black-necked spitting cobra deliberately aim for the eyes of whomever or whatever they feel threatened by. If you're unlucky and by some horrible chance you do, a word of advice: Close your eyes. If you're smart, you'll never come within six feet (two meters) of a spitting cobra.
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |