For one thing, microbes living in a biofilm are rooted in a relatively stable microenvironment where they may have access to a nutrient source.

一方面，对于微生物而言，生物膜形成的微观环境相对稳定，在此微生物拥有营养来源。

If we look at where the teeth are found, they tend to be found in coastal areas where you had very rich nutrient sources to produce a very complex food web.

要是我们看一下牙齿被找到的地方，它们往往是在海岸附近被找到的，那里有非常富集的养分形成了非常复杂的食物网。