SIZE, ABUNDANCE, AND ENERGY USE IN COMMUNITIES

1. The relation between abundance and body size has been modelled as a power function: some authors have reported exponents of -0.75 while others have reported values not significantly different from 0. The former value implies that populations use equivalent amounts of energy regardless of their size, while the latter implies energetic dominance by large species. 2. Much of the disagreement results from the use of inappropriate methods to estimate the exponent. Date are re-analysed using structural regression and reduced major axis (RMA) methods. 3. Most RMA estimates of the exponent are close to -1, consistent with greater energy consumption by small organisms than large in communities.