通过运用复杂的统计数据，沃姆（Worm）和同事们用属、科等的数量预测出地球上未知生物的数量，计算结果为：870万。

Using complex statistics, Worm and colleagues used the number of genera, families, and so on to predict Earth's number of unknown species, and their calculations gave them a number: 8.7 million.

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但是这个南方古猿谱系的特性，以及早期人属的特征都是未知的。

But the identity of that lineage, and the characteristics of early Homo, are unknown.

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自上世纪80年代和法国科学家联手开展研究以来，泰国古生物学家们记录了五个恐龙新属种和六个以前未知的物种。

Paleontologists have documented five new genuses of dinosaurs and six previously unknown species since research began in the 1980s in partnership with French scientists.

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