Spatial Distribution

1. Evaluating & Using General Theories in Ecology Ethan P. White (@ethanwhite) with Xiao Xiao, Daniel J. McGlinn, & Katherine M. Thibault General tests of general theory General theories • General ecological theories explain a broad array of ecological patterns • They facilitate research and management at the scale of climate and land use change • To evaluate general theories rigorously it is necessary touse large amounts of data (to get general results) and multiple predictions (to determine if the theory is right, or just lucky) • We evaluate the Maximum Entropy Theory of Ecology and use it to model diversity at continental scales. Use all available data Use all available predictions Commonness & Rarity Observed Predicted 15745 sites 8802 species 4 major taxa 50 million individuals Spatial Distribution Observed MaxEntmodels Predicted Observed Maximum Entropy models describe the most likely state of a system that satisfies a set on constraints. Body Size & Resource Use Observed Predicted Predicted This MaxEnt model captures commonness and rarity across the globe and diversity of life. When pushed to predict multiple patterns the model produces decidedly mixed results. Using general theories to model diversity Good models for complicated systems without dominant processes (e.g., toddlers and ecology) Predict Rarity Model diversity Specify a joint distribution Subject to constraints Observed # of Rare Species Maximize entropy Environment Predicted # of Rare Species Richness & Abundance We practice open science Extrapolate across scales Poster Code: github.com/weecology Data: weecology.org/data Grants: weecology.org/grants Twitter: @ethanwhite Blog: jabberwocky.weecology.org Theory Birds Predicted Harte et al. (2009) Ecology Letters log(# of Species) Diversity Patterns Acknowledgements Weecology CAREER Award Harte Lab Predicted log(Area)