研究人员现在知道，这些化石属于生活在约两亿五千万年前的古老哺乳动物。
Researchers now know they belong to an ancient relative of mammals that lived around 250 million years ago.
哺乳动物与恐龙同时出现于三叠纪末期，即约两亿两千万年前。
Both mammals and dinosaurs appeared near the end of the Triassic period, some 220 million years ago.
两亿五千两百万年前的二叠纪末期，发生了地球上迄今为止所知的最大一次生物灭绝。
The end of the Permian period, 252m years ago, was marked by the biggest extinctionof life known to have happened on Earth.
大约两亿五千一百万年前，在大灭绝时期，西伯利亚火山的废渣歼灭了95%的海洋生物，陆地上也是差不多情形。
Some 251m years ago, the effluvia of Siberian volcanoes wiped out 95% of life in the seas, and almost as much on the land, in an episode known as the Great Dying.
塞米拉拉煤矿形成于一亿两千万至两亿三千万年前，那时的塞米拉拉煤矿是一片沿海平原，就如同现在美国东南部的墨西哥湾的地质环境一样。
The Semirara coalfields formed from 12-23 million years ago along what was then a coastal plain-similar to the current geologic environment of the southeastern Gulf coast of the United States.
“我们是研究发生在两亿五千两百万年前的事件的古生物学家”，他补充道，“十万年对我们来说仅仅是一个夜晚而已”。
"We're paleontologists studying events 250 million years ago," he adds, so "a hundred thousand years sounds like overnight to us."
例如，发生在两亿五千年前的二叠纪物种灭绝就与西伯利亚的火山爆发发生在同一时期。
The Permian extinction, for example, which happened 250 million years ago, is marked by floods of volcanic rock in Siberia that cover an area roughly the size of western Europe.
例如，发生在两亿五千年前的二叠纪物种灭绝就与西伯利亚的火山爆发发生在同一时期。
The Permian extinction, for example, which happened 250 million years ago, is marked by floods of volcanic rock in Siberia that cover an area roughly the size of western Europe.
应用推荐