There is an element to this, but at the same time things tend to get incredibly messy at the level of whole complex organisms. (Btw., that also holds for mining

There is an element to this, but at the same time things tend to get incredibly messy at the level of whole complex organisms. (Btw., that also holds for mining/geology: you can do a lot of complex measurements from the surface, drill some holes and still be wrong about what you encounter underground).