The people that study ruins are archaeologist.
Archaeologist
study written records
Scattered rubbish ruins can be referred to as "debris" or "litter." In a broader context, it may also be described as "waste" or "garbage," particularly in relation to abandoned or dilapidated sites. If the context is archaeological, these remains might be termed "ruins" or "relics."
The study of laughter is called Gelotology.
orntology .
That person is called an archaeologist. They study human history and prehistory through the excavation of sites and analysis of artifacts.
People who study pathology are called pathologists.
People who study psychology are called psychologists.
ruins mostly.
An archaeologist is the person who digs up ruins to study the past.
People who study bats are called chiropterologists.
Demographers.
Zoologists.
Hemographers
pharmacologists
dictoneran
Sedimentologists.