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

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

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.