During the Ordovician, most life was in the sea, so it was sea creatures such as trilobites, brachiopods and graptolites that were drastically reduced in number.

在奥陶纪，大多数生命都生活在海洋里，所以海洋生物，例如三叶虫、腕足类动物与笔石动物的数量在此时急剧减少。

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Between one edge of the three-foot-thick gray band and the other, some 80 percent of marine species died out, many of them the sorts of creatures, like graptolites, that no longer exist.

在约1米厚的灰色岩石带子的各个带层之间，约80%的海洋物种灭绝了，其中许多是生物物种，象笔石动物，再也不会在这个世界上存在了。

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Between one edge of the three-foot-thick gray band and the other, some 80 percent of marine species died out, many of them the sorts of creatures, like graptolites, that no longer exist.

在约1米厚的灰色岩石带子的各个带层之间，约80%的海洋物种灭绝了，其中许多是生物物种，象笔石动物，再也不会在这个世界上存在了。

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