Ecology, or ecological science, is the study of how interactions among all the elements of an environment affect the distribution and abundance of living organisms. The environment of an organism includes both the physical properties, which can be described as the sum of local abiotic factors like climate and geology, as well as the other organisms that share its habitat. The term oekologie was coined in 1866 by the German biologist, Ernst Haeckel, from the Greek oikos meaning "household" and logos meaning "study"; hence, the "study of the household of nature."