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Evaluating & Using General Theories in EcologyEthan P. White (@ethanwhite) with Xiao Xiao, Daniel J. McGlinn, & Katherine M. Thibault

15745 sites8802 species4 major taxa50 million individuals

Code: github.com/weecology Data: weecology.org/data Grants: weecology.org/grants Twitter: @ethanwhiteBlog: jabberwocky.weecology.org

MaxEnt models

General tests of general theoryGeneral theories

Using general theories to model diversity

Theory

Diversity Patterns

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• 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 to use 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

Body Size &Resource Use

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Commonness& Rarity

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Maximum Entropy models describe the most likely state of a system that satisfies a set on constraints.

Good models for complicated systems without dominant processes (e.g., toddlers and ecology)

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.

𝑅 (𝑛 ,𝜀|𝑆0 ,𝑁0 ,𝐸0 , 𝐴0¿

∑𝑛=1

𝑁0

𝑛 ∙ Π (𝑛|𝐴 ,𝑛0 , 𝐴0 )=𝑁 0𝐴𝐴0

Specify a joint distribution

Maximize entropy

Subject to constraints

We practice open science

Predict Rarity

Extrapolate across scales

Model diversity

Environment

Richness & Abundance

Harte et al. (2009)Ecology Letters

Acknowledgements

Poster

HarteLab

CAREERAward

Weecology Predicted

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