Ernest, S. K. M.,Enquist, B. J.,Brown, J. H.,Charnov, E. L.,Gillooly, J. E.,Savage, V.,White, E. P.,Smith, F. A.,Hadly, E. A.,Haskell, J. P.,Lyons, S. K.,Maurer, B. A.,Niklas, K. J.,Tiffney, B.
Ecosystem properties result in part from the characteristics of individual organisms. How these individual traits scale to impact ecosystem-level processes is currently unclear. Because metabolism is a fundamental process underlying many individual- and population-level variables, it provides a mechanism for linking individual characteristics with large-scale processes. Here we use metabolism and ecosystem thermodynamics to scale from physiology to individual biomass production and population-level energy use. Temperature-corrected rates of individual-level biomass production show the same body-size dependence across a wide range of aerobic eukaryotes, from unicellular organisms to mammals and vascular plants. Population-level energy use for both, mammals and plants are strongly influenced by both metabolism and thermodynamic constraints on energy exchange between trophic levels. Our results show that because metabolism is a fundamental trait of organisms, it not only provides a link between individual- and ecosystem-level processes, but can also highlight other import-ant factors constraining ecological structure and dynamics.