Then, you cool down the milk a little bit, and add some heat-loving, or thermophilic, bacteria.

然后，稍微冷却一下牛奶，再加入一些。

One of the things we know, for instance, is that the “oldest” organisms, the ones that are nearest to the last common ancestor, are all thermophilic organisms.

所知，像这些生物非常相似于远古的那些生物都是这样的温生物。