So, basically, the animal kingdom is much newer than the archaean kingdom.

所以，动物比古生菌出现的晚。

The tentacled Archaean uses proteins common to multicellular organisms and might lend insight into how the latter evolved.

这种有触角的太古代微生物使用多细胞生物共有的蛋白质，这可能有助于我们了解后者进化的方式。

It existed 2.7 to 2.5 billion years ago, toward the very end of the Archaean Eon.

它存在于 2.7 到 25 亿年前， 接近太古宙末期。

The bacterial realm, Mayr notes, consists of no more than a few thousand species while the archaean has a mere 175 named specimens, with perhaps a few thousand more to be found-but hardly more than that.

迈尔指出，微生物界只由几千种组成，而原始细胞只有175种已经命名的样本，也许还有几千种未被发现——“但不大会多于那个数字”。