英語(yǔ)時(shí)差:害怕被劍齒虎咬

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D:Hey,Yale.Would you rather be bitten by a saber-toothed tiger or a modern day tiger? Y:Neither,of course.But if I have to pick,I supposed I choose the modern tiger.Since the saber-toothed tiger massive fangs. D:Well,you may be surprised to learn that paleontologists now think that despite their huge, fearsome looking canine teeth, the prehistoric American sabercat, Smilodon fatalis, had a bite force only about one-third as strong as modern big cats. Y:How can they told that from fossilized bones? D:They used very fine CT scans of the skull, jaw and neck bones to create a highly detailed 3 D computer model. Then using careful analysis of the size and placement of muscle attachment points and mathematical modeling they were able to calculate the power of the jaw muscles and the bite force of the now extinct sabercats.This was the most detailed computer model ever created for a vertebrate. Y:Neat!So if they had such a wimpy bite, what’s with the huge fangs? D:The function of the sabercat’s eight inch teeth is one of the longest running debates in paleontology. The results of this study support the hypothesis that the sabercats brought down and subdued large prey, like mammoths, with their strong forelimbs.Once the prey was safely restrained on the ground, sabercats used their large fangs to pierce through the thick hide on the neck of their quarry.In contrast, modern day big cats use their more powerful jaws to bite the neck of their prey for an extended period to subdue them by asphyxiation. Y:Yikes!I think I'll pass on being bitten by either a sabercat or a modern day tiger. D:Wise choice.