【英语时差8,16】群居的剑齿猫

（单词翻译）

 Social Saber-Toothed Cats What’s more dangerous than meeting one saber toothed cat? Meeting a gang of them. The saber toothed cat, Smilodon fatalis, existed in North and South America until 10,000 years ago. It was lion sized, but with a heavier build and a short tail like a bobcat. Being one of the most preserved species at the La Brea Tar¹ Pits of Los Angeles, Smilodon is most famous for its seven inch long canine² teeth, but its behavior remains³ shrouded⁴ in mystery.Did it live alone or in groups? Some scientists suspect Smilodon was a social cat like the lion, coming to the tar pits to feed on animals trapped in the sticky goo. Of course, the big cats were often trapped too. Surprisingly, their fossils contained healed injuries and debilitating⁵ arthritis⁶. Was this a sign that old and wounded cats were supported by other group members? Scientists didn’t think so, but weren’t positively⁷ sure. So, scientists conducted a unique experiment, comparing the abundance of Smilodon fossils at the tar pits with the number of modern predators⁸ responding to playbacks in Africa. The playbacks were recordings⁹ of distressed¹⁰ prey¹¹ animals, mimicking¹² the conditions at the tar pits thousands of years ago. Playbacks attracted lions, hyenas¹³, and jackals, all social predators. Solitary¹⁴ predators were rare visitors. This was an unexpected finding, since there are fewer social predators than solitary ones in the African population. When they compared data, scientists were excited to find that the proportion of social predators attracted to the playbacks in Africa matched the proportion of Smilodon fossils found at the tar pits.This evidence suggested Smilodon lived in groups. It seems, meeting a saber toothed gang may have been the rule, not the exception.