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一、毒蛇蛇在自然界属于脊索动物门,脊椎动物亚门,爬行纲,有鳞亚纲,蛇目。最早的化石蛇类发现于距今七千五百万年前的白垩纪地层。蛇的出现时间应该还要早些,可能在侏罗纪。现代的爬行动物中,蛇目与蜥蜴目的关系最接近。有许多证据足以说明蛇是古代的某类蜥蜴演化而来。现今世界上生存的蛇类已知约有2200种,隶394属8科。其中毒蛇600余种,而对人有致命危险的毒蛇有300种,但目前能查实的主要毒蛇为195种(印度、东南亚、远东、澳大利亚和太平洋地区共82种,非洲45种,欧洲、近
First, the serpent snake in nature belongs to the chordata door, vertebrate sub-door, reptiles, scales subclass, snake orders. The earliest fossil snakes were found in Cretaceous strata dating back 75 million years ago. Snake’s appearance time should be even earlier, probably in the Jurassic. In modern reptiles, snakes and lizards the purpose of the closest relationship. There is much evidence that the snake is a kind of ancient lizard evolution. About 2200 species of snakes exist in the world today, with 394 genera and 8 families. There are over 300 venomous snakes, while 300 venomous snakes are fatal to humans. However, there are currently 195 major venomous snakes (84 in India, Southeast Asia, the Far East, Australia and the Pacific, 45 in Africa, and Europe