Sea urchins are perhaps best known for their armor of spines .

也许关于海胆，人们知道得最多的是它们的棘刺盔甲。

Bottom-dwelling creatures like mussels , brittle stars and sea urchins have not developed any defenses .

类似贻贝、海蛇尾和海胆这样生活在海底的生物尚未演化出任何防御能力。

Sea urchins bore through rock to carve out nooks , where they can protect themselves from waves and predators .

海胆在岩石上钻孔，为自己开凿出藏身之所，以躲避海浪和天敌的袭击。

Now scientists are solving the mystery of how urchins keep their teeth so keen , and the research could lead to self-sharpening tools .

现在科学家正在解开海胆牙齿永不变钝之谜，而这项研究将可能促进研发自锐工具。

An orthodontist 's dream , an atlantic wolffish displays the hardware it uses to crush mollusks , shellfish , and sea urchins .

牙齿矫正医师的梦想，太平洋狼鱼炫耀着它用以收拾软体动物，贝壳和海胆的装备。