Why would a life scientist study a non-living thing like a lame or a rock? idk

A scientist would study a nonliving things as a lake or a rock because those things might have believe it or not it can have minerals or vitamins we need in our bodies or something. A scientist might also study a part of the habitat a living thing is living in to see if the lake may have bacteria or what elements it consists of. For example if it's freshwater or salt water.

Rocks may look boring and useless but there are minerals inside that may fascinate a scientist