Notes by Peter P. Sir, copyright What is Ecology? Define Ecology Ecology is the scientific study of the relationship and interactions between organisms and their environment. The term ecology is derived from the Greek word Oekologie where “Oikos” meaning “household” and “logos” means “the study of”. The word "ecology" ("Ökologie") was coined in 1866 by the German scientist Ernst Haeckel . Ecology is a branch of biology concerning interactions among organisms and their biophysical environment, which includes both biotic and abiotic components. The ecosystem is the fundamental unit of ecological studies. Ecology is not synonymous with environmentalism, natural history, or environmental science. It overlaps with the closely related sciences of evolutionary biology, genetics, and ethology. An important focus for ecologists is to improve the understanding of how biodiversity a...