All ecosystems together make up the biosphere, the thin layer of life that encircles the earth. Interactions between populations in an ecosystem tend to keep the system relatively stable. Food relationships form a major part of interaction between populations. A constant supply of solar energy is required for an ecosystem and for life to exist. Require plentiful sun and rainfall all year long.
Human populations tend to modify existing ecosystems for own purposes.
Fewer ecosystems are able to function adequately to sustain human populations. Preservation of biodiversity is extremely important. Taxonomy is the biological discipline of identifying and classifying organisms. Scientific name is a binomial. System was started by Swedish naturalist Carolus Linnaeus.