How did the first yoghurt get fermented since there were no yoghurt to ferment milk then?

Question

So basically, we need a little amount of yoghurt in order to ferment a pot of milk into yoghurt. Then, how did the first yoghurt ever get fermented without no yoghurt before?

In: Other

Answer 1

Yoghurt is made by fermenting milk with certain bacteria. That is what you need. Using a little yoghurt to start a new batch is just an easy way to do it, because it already has the bacteria.