时差N小时:害怕被剑齿虎咬

Don：Hey, Yale. Would you rather be bitten by asaber-toothed tiger or a modern day tiger?

唐：嘿，雅艾尔。你宁愿被剑齿虎咬还是被现代的老虎咬?

Yael：Neither, of course. But if I have to pick, Isupposed I choose the modern tiger. Since thesaber-toothed tiger massive fangs.

雅艾尔：都不愿意。如果一定要选的话，我情愿选现代的老虎。因为剑齿虎长有巨大的獠牙。

Don：Well, you may be surprised to learn that paleontologists now think that despite theirhuge, fearsome looking canine teeth, the prehistoric American sabercat, Smilodon fatalis,had a bite force only about one-third as strong as modern big cats.

唐：不过，古生物学家认为除了巨大的、长相可怕的犬齿之外，美国史前剑齿虎 Smilodon fatalis 的咬合力只有现代大猫的三分之一，知道这一点你可能会觉得很惊讶。

Yael：How can they told that from fossilized bones?

雅艾尔：他们是如何根据骨头化石得知咬合力的?

Don：They used very fine CT scans of the skull, jaw and neck bones to create a highlydetailed 3 D computer model. Then using careful analysis of the size and placement of muscleattachment points and mathematical modeling they were able to calculate the power of thejaw muscles and the bite force of the now extinct sabercats. This was the most detailedcomputer model ever created for a vertebrate.

唐：他们用精密的CT扫描仪扫描头骨，颚和颈椎骨，用来建立一个高度精确的3D电脑模型。然后仔细分析肌肉附着点的尺寸和位置，利用这些数据进行数学建模，这样他们才能够计算出目前已经灭绝的剑齿虎的颚肌的力量和咬合力。这是人们迄今建立的最精确的脊椎动物电脑模型。

Yael：Neat! So if they had such a wimpy bite, what's with the huge fangs?

雅艾尔：做得好!那么如果它们的咬合力小，那么这些獠牙还有何用?

Don：The function of the sabercat's eight inch teeth is one of the longest running debates inpaleontology. The results of this study support the hypothesis that the sabercats broughtdown and subdued large prey, like mammoths, with their strong forelimbs. Once the prey wassafely restrained on the ground, sabercats used their large fangs to pierce through the thickhide on the neck of their quarry. In contrast, modern day big cats use their more powerfuljaws to bite the neck of their prey for an extended period to subdue them by asphyxiation.

唐：剑齿虎的门牙有八英尺长，至于它的作用至今仍是古生物学届最持久的争议话题之一。这项研究的结果支持这种假说：剑齿虎使用强壮的前肢扑倒和制服像猛犸象这样的大型猎物。一旦猎物被彻底制服在地上，剑齿虎便用它那巨大的獠牙刺穿猎物脖子上的厚皮。相反，现代的大猫则利用更锋利的颚来长时间咬住猎物的脖子，直到它们窒息而亡。

Yael：Yikes!I think I'll pass on being bitten by either a sabercat or a modern day tiger.

雅艾尔：呀!我想在剑齿虎或者现代老虎咬我的时候，我就会不行了。

Don：Wise choice.

唐：明智的选择。