Imperial College London

Samraat Pawar

Faculty of Natural SciencesDepartment of Life Sciences (Silwood Park)

Professor of Theoretical Ecology



+44 (0)20 7594 2213s.pawar CV




2.4KennedySilwood Park




Research themes


All organisms live with two major constraints: their temperature, and their body (or cell) size. Both factors govern rates at which individuals gather and use energy and thus ultimately, population dynamics and fitness. The effects of temperature and size are intimately related. Temperature especially in ectotherms, accelerates metabolic rate (to a point), which also scales with size. We study how temperature and size together drive interactions between individuals, and what physiological strategies can be successful in different environments. A major area of focus of the lab is currently on understanding rates of interaction-mediated acclimation and adaptation to changing environmental temperatures in autotrophic and hetrotrophic microbes.


Species interactions form large, complex networks that generate interesting and sometimes unpredictable ecosystem dynamics. Understanding how these complex systems arise and persist, and how they influence the fate of organisms embedded in them, is a fundamental problem that has occupied biologists for almost two centuries. We study how interaction network structure affects populations, and how ecosystem-level network structure in turn emerges from assembly of interacting pairs of populations. To quantify interactions, we use metabolic theory to model effects of size- and temperature-mediated constraints on individuals. Two main areas of focus currently is the effect of temperature on the assembly and persistence of microbial communities.


Most organisms live in thermally fluctating environments. An then, there is the small matter of the ongoing global climate change. Building on our work with the metabolic basis of complex species interaction networks, we study how short-term fluctuations as well as long term directional changes in environmental temperature affect ecosystem functioning (especially, carbon cycling). An then, there is the small matter of unprecendented global climatic changes in climate (especially in temperature) currently taking place due to human activities. A current area of focus is microbial communities, which are major "movers and shakers" in the global carbon cycle, with our ultimate goal being to integrate the dynamics of microbial communities into the wider ecosystem's dynamics.