Of course, if you've seen one elderly Asian sheepshead wrasse, you've seen them all.

当然，如果见过一只年老的，就见过所有的了。

One good sign of health for our oceans is the mere existence of older fish, like this Asian sheepshead wrasse in the China Sea.

海洋健康的一个征兆就是较老的的存在，譬如说这只在中国海的。