Colonel, just a squashed up version of colonel.

上校，只是压扁版的上校。

But why are archaea so important? Why do they need a whole biological domain to themselves, while we humans get squashed up in one domain with plants and fungi?

为什么古生菌如此重要？为什么它们能单独成为一个分类？然而我们人类要和植物、真菌挤在一个分类里？