He doesn't just use his to catch crabs. 它不光用颌来抓螃蟹
Some fish use them to protect their eggs. 有的鱼用颌来保护自己的卵
But there is more to jaws than that. 但是颌的作用不止于此
The pairing of backbones with jaws was to prove a winning combination. 颌搭配脊椎是胜利的组合
the juvenile's jaws are not yet strong enough to break its shell. 幼鱼的颌尚不够强大 无法咬破它的壳
Just what it needs to outmaneuver the young fish. 刚好能够摆脱这条年轻的鱼
Dunkleosteus has the pace to catch up with them. 邓氏鱼的速度能够追上菊石
there was to be a changing of the guard. 即将发生权力转移