Can Temperature Alone Affect Cellular Structuring,Thereby Reducing Basal Metabolic Demands within Micropterus salmoides

Evidence supports that, within an organism, muscle fibers tend to increase in size until they approach diffusion limitations because smaller fibers are metabolically more costly to maintain than larger fibers. However, diffusion limitations themselves are dependent on temperature, and by increasing temperatures such constraints may be loosened. Such an effect could potentially have reverberating consequences on ecosystem balances in the face of global climate change. Therefore, we tested whether temperature alone could affect the physiological structuring of muscle tissues, and if such a restructuring could influence the basal metabolic demands of the individual. Specifically, we coupled metabolic rate measurements with microscopy of muscle fibers within the musculature of Micropterus salmoides at different temperatures. Results indicate that organisms respond by restructuring cell sizes to re-approach diffusion constraints, and that this affects resting metabolic rates. Physiological effects of temperature such as this should be considered as models are increasingly applied to project future effects of climate change, especially in the areas of bioenergetics and changes in population distribution.