它们就是寄生虫的“酒店”，甚至它们的寄生虫也有寄生虫。

They're just parasite hotels, even their parasites have parasites.

youdao

这里有一个可能性，它可能产生于你第一次吸食你母亲的母乳时，最早的细菌建立了自己的族群并选择它们的寄生者。

Here's a possibility: it may turn out that when you take your first drink from your mother's breast, the earliest bacteria set up shop and decide who gets to follow.

youdao

寄生虫通常比它们的宿主小。

Parasites are usually smaller than their hosts.

youdao