在过去数百年间，人们发现了数千块史前鲸骨上面划有深深的沟痕。

　　They're found on ribs, vertebra, tail flukes and flipper bones, and some of them are over 9 inches long and in some cases, 3 inches deep.

　　在鲸的肋骨、脊椎骨尾叶和鳍肢骨上都有发现这些沟痕，有些长近9英寸有些深度近3英寸。

　　The force to drive teeth that deep into bone would have been staggering.

　　能把牙齿咬入骨头那么深的力量可是相当惊人。

　　But even more importantly, the size of the animal who could inflict an injury of that nature would have been unimaginable.

　　不过更重要的是，能够造成那种性质的伤害的动物其体型真是难以想象。

　　The evidence points to a top predator whose scale is almost unimaginable - a giant monster who roamed the seas.

　　证据指向一种顶级掠食者，它有着几乎无法想象的庞大身躯——一个在海中游荡的巨怪。

　　Somewhere out there was a giant whale killer.

　　在大海里的某处有着巨大的鲸之杀手。

　　Next to many of these injured bones, paleontologists found something else.

　　在很多这些有伤痕的骨头的旁边，古生物学家们发现了别的东西。

　　Triangular shaped teeth, which were absolutely enormous.

　　三角形的牙齿，数量绝对庞大。

　　They had serrated edges which could used to cut through the flesh of large prey.

　　它们边缘呈锯齿状可以用来切割大型猎物的肉。

　　When they tried to fit the teeth with the gashes in the bones, they discovered a match.

　　古生物学家们试着把牙齿放进骨头上的裂缝，发现完全吻合。

　　So if we look at this bone there's an asymmetrical cut in it and the only way this tooth will fit in is in this position,如果我们看看这些骨头，它上面有不对称的切痕，这种牙齿唯一能跟这吻合的就是这种姿势，because we have the upper surface of the cut is very flat... the lower surface is sloped.

　　因为我们看到切口的上表面很平整，而下表面则有斜坡。

　　And the tooth will only fit in, in that position.

　　牙齿只能用姿势才能正好插入。

　　And there's no other animal produces a bite with that asymmetry.

　　没有别的动物能够咬得那么么不均匀。

　　The teeth belonged to the giant shark. Megalodon.

　　这些牙齿来自巨大的鲨鱼。巨齿鲨。

　　Megalodon the name itself literally means long tooth.

　　巨齿鲨这个名字字面意思为“长牙”。

　　And it's a little bit of misnomer because it really is more than just long, it's huge.

　　其实有一点儿不妥，因为这些牙齿可不仅仅是长，而是巨大。

　　So this is a Megalodon tooth.

　　这是一枚巨齿鲨的牙齿。

　　It looks much like a modern Great White tooth.

　　看起来很像现代大白鲨的。

　　The edges are serrated like a steak knife, very blade like.

　　边缘像牛排刀一样有锯齿，很像刀刃。

　　Megalodon could reach a mind-blowing 15 meters or more in length, three times the size of a Great White and about the size of a modern private jet.

　　巨齿鲨的体长能达到惊人的十五米甚至更长，是大白鲨体长的三倍相当于一架现代私家喷气机。

　　This animal is so huge. It is so enormous.

　　这种动物太大了。它是那么庞大。

　　If Megalodon existed at the time when man existed, we would not have been able to venture into the ocean,如果大白鲨生活在人类存在时，我们根本就不敢冒险下海，because we couldn't build a ship big enough to deter him from attacking it.

　　因为我们造不出够大的船能免遭它的攻击。