Biology
Biology is the natural science that involves the study of life and living organisms, including their physical structure, chemical composition, function, development and evolution. Modern biology is a vast field, composed of many branches. Despite the broad scope and the complexity of the science, there are certain unifying concepts that consolidate it into a single, coherent field. Biology recognizes the cell as the basic unit of life, genes as the basic unit of heredity, and evolution as the engine that propels the creation of new species. Living organisms are open systems that survive by transforming energy and decreasing their local entropy to maintain a stable and vital condition defined as homeostasis. See glossary of biology.
Ecology
Ecology (from Greek: οἶκος, "house", or "environment"; -λογία, "study of") is the branch of biology which studies the interactions among organisms and their environment. Objects of study include interactions of organisms with each other and with abiotic components of their environment. Topics of interest include the biodiversity, distribution, biomass, and populations of organisms, as well as cooperation and competition within and between species. Ecosystems are dynamically interacting systems of organisms, the communities they make up, and the non-living components of their environment. Ecosystem processes, such as primary production, pedogenesis, nutrient cycling, and niche construction, regulate the flux of energy and matter through an environment. These processes are sustained by organisms with specific life history traits. Biodiversity means the varieties of species, genes, and ecosystems, enhances certain ecosystem services.
Ecosystem
An ecosystem is a community made up of living organisms and nonliving components such as air, water, and mineral soil. Ecosystems may be studied either as contingent collections of plants and animals, or as structured systems and communities that are governed by general rules. The biotic and abiotic components interact through nutrient cycles and energy flows. Ecosystems include a network of interactions among organisms, and between organisms and their environment. Ecosystems can be of any size but one ecosystem has a specific, limited space. Some scientists view the entire planet as one ecosystem.
Biology
The ultimate aim of the modern movement in biology is in fact to explain all biology in terms of physics and chemistry.
Francis Crick (1966) Of Molecules and Men. p. 10.
Ecosystem
If we recognise that every ecosystem can also be viewed as a food web, we can think of it as a circular, interlacing nexus of plant animal relationships (rather than a stratified pyramid with man at the apex)... Each species, be it a form of bacteria or deer, is knitted together in a network of interdependence, however indirect the links may be.
Murray Bookchin, The Ecology of Freedom (1982).
Biology
No biologist today would think of submitting a paper entitled "New evidence for evolution;" it simply has not been an issue for a century.
Douglas J. Futuyma, Evolutionary Biology, 2nd ed., 1986, Sinauer Associates, p. 15