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青蛙以小动物为食,其中害虫约占80%。据统计,每只青蛙每天约吃60多只害虫,从春到秋的七、八个月中,能消灭害虫一万多只。每亩放养400～800只青蛙的早稻田,不再放农药,比喷洒两次“甲基1605”的对照田,枯心率大大降低,而粮食可增产9.2%。可见,青蛙对于人类是很有益处的。但是,我们能不能称青蛙为“益虫”呢?按照动物学的分类方法,“身体分为头、胸、腹三部分;头部有触角一对、复眼一对,口器一个;胸部有足三对,一般有翅两对”的蚊、蝇、蝗虫、家蚕等动物,属节肢运动门的昆虫纲(纲下还分目、科、属、种);而“皮肤裸露,能分泌粘液;幼体生活在水中,用鳃呼吸;成体生活在陆上,也能生活在水中,用肺并兼用皮肤呼吸”的动物划在脊索动物门的两栖纲内,从青蛙的特征来看,它不是“昆虫”,而是“两栖动物”。所以,我认为青蛙以不称“益虫”,而称“有益的两栖动物”或“有益动物”为妥。
Frogs feed on small animals, of which pests account for about 80%. According to statistics, each frog eat about 60 pests daily, from spring to autumn seven or eight months, to eliminate more than 10,000 pests. Farms with 400 to 800 frogs per mu were no longer provided with pesticides. Compared with the control plots sprayed twice with “methyl 1605”, the withered rate was greatly reduced while the grain yield increased by 9.2%. So, frogs are good for humans. However, we can call the frog “beneficial insects”? According to zoology classification method, “the body is divided into three parts of the head, chest and abdomen; the head has a pair of antennae, a pair of paws, a mouthpart; Three pairs of, generally winged two pairs of ”mosquitoes, flies, locusts, silkworms and other animals, is an arthropod door insects Gang (also under the program, subjects, genera and species); and“ naked skin can secrete mucus; The larvae live in the water and breathe through the gills. The animals that live on land, live in the water, breathe in the lungs and use both skin and breath, are drawn in the amphibia of the phylum Chorax. From the frog's point of view, it is not ” Insects “, but” amphibians. “ So, I think the frog is not called ”beneficial insects,“ and called ”beneficial amphibians“ or ”useful animals" properly.