But we know that nonmammalian animals can replace their cells, and those creatures' cells are dying and being replaced throughout life, so the animals maintain normal hearing.

但我们知道，非哺乳动物能够更换它们的（毛）细胞，这些生物的（毛）细胞在一生中不停地死亡、更换，使得这些动物能维持正常听力。