Why scientists know more about the cenozoic than they do about other eras

Explanation:

they know more about the Cenozoic era because this is the only era that has had a wide diversity of species living on Earth. they know more about the Cenozoic era because this is the most recent time period in the history of the Earth, and we have more information available to study.

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.