Research interests: metabolic theory of ecology, community assembly rules, morphological evolution, body size distributions, biodiversity, ecological stoichiometry, human macroecology, theoretical biology, allometry, major evolutionary transitions, evolutionary ecology, scaling of organelles, allometric scaling and metabolic ecology of unicellular organisms, microbial macroecology, astrobiology, theoretical biogeochemistry 

Research synopsis
My  research centers around investigating the effects of the size, metabolism, and temperature of biological systems on the properties of these systems, from cells and individuals to communities and ecosystems, and the implications of these effects for understanding the ecology and evolution of these systems. I employ approaches from mathematics, biophysics, geochemistry, macroecology, evolutionary biology, and molecular ecology to address these questions.

Currently, I am in my first year of a postdoctoral project funded by fellowships from Arizona State University's School of Earth and Space Exploration and NASA's Astrobiology Institute Postdoctoral Program. In collaboration with Everett Shock and Jason Raymond at ASU and Tori Hoehler at NASA, I am developing and evaluating theory based on geochemistry, thermodynamics, kinetics, and bioenergetics to elucidate fundamental physicochemical constraints on the evolution and geographic distribution of metabolic diversity.

My past and current research involves the following broad themes:

1) The relationship between allometric scaling and the major evolutionary transitions of life
2) The allometry and metabolic ecology of organelles, cells and microorganisms 
3) The role of size, temperature, and stoichiometry in governing the tempo and mode of evolution, the structure and dynamics of ecological communities, the metabolism of ecological systems, and the geographic distribution of biodiversity 

4) Assembly and diversity of microbial genes, taxa, and traits along extreme temperature gradients of Yellowstone hot springs and Antarctic lakes

Selected Publications
•  DeLong, J.P., J.G. Okie, M.E. Moses, R.M. Sibly, and J.H. Brown. 2010. Shifts in metabolic scaling, production, and efficiency across major evolutionary transitions of life. Proceedings of the National Academy of Sciences 107:12941-12945. (Supporting Information).
•  Okie, J.G., and J.H. Brown. 2009. Niches, body sizes, and the disassembly of mammal communities on the Sunda Shelf islands. Proceedings of the National Academy of Sciences 106:19679-19684. (Supporting Information).