单词ratfish
n.: 【动】银鲛属 的鱼网络: 兔银鲛；鼠鱼；鼠鲨
【动物;动物学】银鲛属的鱼
I soon realized that the ratfish "s tendency to swim against the flow might help to answer my questions.
不久后我就知道，鼠鱼逆水而游的习性或许有助于回答我想问的问题。