Why is it important to classify the millions of species on Earth?
to have common names that everyone can remember
to more easily sequence their genetic material
to create scientific names that only scientists can learn
to organize them and speak about them accurately

not sure if this is what you'r looking for eubacteria and archaebacteria

they had the law tat factories that produces smoke cannot be built near residential buildings.

building of proper sewage system was done to ensure that the waste is carried away from the humans so that they do not get diseases from it.

also they built water systems to provide water in those areas which are drought prone.