Metabolic theory of ecology The metabolic theory of ecology
(MTE) is an extension of Kleiber's law and posits that the
metabolic rate of organisms is the fundamental biological rate
that governs most observed patterns in ecology. MTE is based on
an interpretation of the relationships between body size, body
temperature, and metabolic rate across all organisms. Small-
bodied organisms tend to have higher mass-specific metabolic
rates than larger-bodied organisms. Furthermore, organisms that
operate at warm temperatures through endothermy or by living in
warm environments tend towards higher metabolic rates than
organisms that operate at colder temperatures. This pattern is
consistent from the unicellular level up to the level of the
largest animals on the planet. In MTE, this relationship is
considered to be the single constraint that defines biological
processes at all levels of organization (from individual up to
ecosystem level), and is a macroecological theory that aims to
be universal in scope and applicat