Demography from the greek 'Demos'
Epidemiology is the study of factors affecting the health and illness of populations. The specialist is called an epidemiologist.
populations
Hemographers
demographic
demography
the study of cells, the study of organisms, and the study of populations
It is called social studies
Entomologists study the life of, populations of and behaviors of Insects. Entomology is literally the "study of insects"
Demographs
populations
demography
so you can know the number of animals there are in the species