The disappearance of megafauna in America—mammoths, saber-toothed cats, giant sloths, among others—happened relatively soon after the arrival of human beings, about 13,000 years ago.
美洲巨型动物的消失——猛犸象、剑齿猫、巨型树懒等等——发生在人类出现后不久，大约在一万三千年前。
2
See "Odd Saber-Toothed Beast discovered-preyed on... Plants?"
另见“奇异剑齿兽被发现——食的是……草？”
3
The "saber-toothed squirrel" study was published today in the journal Nature.