为了保证总有满口锋利牙齿，犹他盗龙有一种特殊的适应力。

And to ensure it always had a fresh set, Utahraptor had a special adaptation.

锯脂鲤属的有着锋利牙齿的水虎鱼是和纳氏锯脂鲤是世界上最残忍的淡水鱼类。

The razor-toothed piranhas of the genera Serrasalmus and Pygocentrus are the most ferocious freshwater fish in the world.

梅丽莎·汤普森在25.94秒内写了这条短息：“锯脂鲤属的有着锋利牙齿的水虎鱼是和纳氏锯脂鲤是世界上最残忍的淡水鱼类。

Melissa Thompson wrote the message the razor-toothed piranhas of the genera Serrasalmus and Pygocentrus are the most ferocious freshwater fish in the world.