Being a vertebrate, 作为脊椎动物

274. And this juvenile has spotted something out in the blue.
     这条幼鱼在蓝色的海洋中有所发现
275. Ammonoids,
     菊石
276. close relatives of today's deep-sea nautilus.
     今天深海鹦鹉螺的近亲
277. Being a vertebrate,
     作为脊椎动物
278. Dunkleosteus has the pace to catch up with them.
     邓氏鱼的速度能够追上菊石
279. But the ammonoids boast a trick of their own...
     但是菊石也有自己的本领
280. ...jet propulsion.
     喷射推进

来自《我们星球上的生命 第一季 第二集 Life on Our Planet S01E02 第一前线》第 277 行