T h e   M a m m o t h   F a u n a .  The teeth structure.     The mammoths teeth are similar to large graters. Each tooth consists of the separate dentine slices covered with enamel. The slices are fastened with each other by interlayers of cement. The tooth crown has the oval form, the crests of slices stand out on it surface, forming the rigid projections. Such teeth are very well adapted to a wearing of food. Each jaw of a mammoth has only two teeth.   Mammoth teeth from Museum of Siberian Natural History. From chewing of food they are gradually erased. In the certain time the new teeth begin to grow on behind them. They support the erasing teeth, gradually displacing them. The old teeth fall out and the new ones appear in place of them. During the life a mammoth had six changes of the teeth. The dairy teeth change thrice then the molar teeth change thrice.   The front upper incisors - the tusks - do not change so frequently. In infancy the young mammoths have the dairy tusks only some centimeters in length, they are not visible at all on a surface. Then they fall out and already the real tusks appear and grow during the all life.