海牛吃什么?海牛是植食性动物,也是已知的唯一一种只吃植物的水生哺乳动物。一头海牛每天要吃大约45千克沉水植物,相当于它自身体重的十分之一。如果换算成生菜的话,这样的食量相当于大约200棵!它们像牛一样伏在草丛中慢吞吞地吃草,所以人们亲切地称它们为“海牛”。科学家认为海牛原本是陆地居民,是大象的远亲。但在近亿年前,由于自然环境的变迁,它们被迫到海洋里谋生,却依旧保持着食草的习性。海牛具有强大的咀嚼能力,这要归功于它们取之不尽的牙齿。海牛的牙齿又宽又平,口腔后边能不断长出新的臼齿,并且新臼齿能向前推移,替代前边被磨损的臼齿。新臼齿前移的速度为每月1~2毫米。海牛一生都在换牙,即使老了也会长出新牙。 What is a manatee? A manatee is a herbivore and is the only aquatic mammal known to eat only plants. A manatee consumes about 45 kg of submerged plant per day, which is equivalent to one tenth of its own weight. If converted into lettuce, this food intake is equivalent to about 200! They like cattle in the grass slowly grazing, so people affectionately call them “manatee ”. Scientists believe the manatee was originally a land-based resident of the elephant. However, nearly 100 million years ago, due to the change of the natural environment, they were forced to make a living in the sea while still maintaining the habit of eating grass. Manatees have a strong ability to chew, thanks to their inexhaustible teeth. Manatee’s teeth are wide and flat, with new molars continually growing behind the mouth, and the new molars can move forward to replace the worn molars. The new molars advance speed of 1 to 2 mm per month. Manatees are changing their teeth all their lives, even if the old will grow new teeth.