DOI: 10.5061/dryad.5hqbzkhgb
title: How the equilibrium assumption is addressed in empirical tests of major ecological theories

description: The idea that natural systems tend to be at equilibrium dates back to the
 origin of the field of ecology and continues to underlie most ecological
 theory. However, empirical evidence for equilibrium dynamics in nature and
 in experiments is surprisingly elusive. Here, we address this conundrum by
 first exploring the history of equilibrium in ecological theory and the
 evidence for equilibrium dynamics in natural systems. We then search the
 literature to quantify how empiricists deal with equilibrium in their
 research, and we address barriers to integrating equilibrium into
 empirical work by providing step-by-step instructions for determining
 whether a population is at equilibrium. Next, we lay out three ways that
 equilibrium is embedded in theory, and for each, outline when meeting the
 equilibrium assumption in empirical tests is critical for scientific
 inference, and when it is possible to relax this assumption. And finally,
 we present concrete steps that empiricists and theoreticians can each take
 in order to meet in the middle when it comes to equilibrium. We hope that
 this paper will stimulate new discussions from researchers from across the
 theory-empirical divide about this longstanding issue.
description: This dataset is the outcome of a Web of Science search on July
 24th, 2024 of the top cited articles that test five major
 equilibrium-based ecological theories: Modern Coexistence Theory, Tilman’s
 resource ratio (R* theory), the Metabolic Theory of Ecology,
 Metapopulation Theory, and Neutral theory. We developed search strings
 iteratively, adding in additional terms highly specific to those theories
 (e.g., "stabilizing niche differences" for Modern Coexistence
 Theory) in order to capture a substantial portion of the literature.
 Abstracts were screened to verify that the papers involved empirical tests
 of the theory’s predictions, and we retained 10 papers for each theory,
 for a total of 50 papers. 
description: # Data for: The equilibrium conundrum Tess N. Grainger, Keila Stark,
 Chuliang Song, Matthew A. Barbour, Rachel M. Germain
 [https://doi.org/10.5061/dryad.5hqbzkhgb](https://doi.org/10.5061/dryad.5hqbzkhgb) ## Context The equilibrium concept is ubiquitous in ecology, yet the ways in which it is considered and applied in different ecological theories varies significantly. We investigated how often the top-cited papers in common ecological theories acknowledge and address the equilibrium assumption. We conducted a Web of Science search on July 24th, 2024, of the top cited articles that test five major equilibrium-based ecological theories: Modern Coexistence Theory, Tilman’s Resource Ratio (R*) Theory, the Metabolic Theory of Ecology, Metapopulation Theory, and Neutral theory. We developed search strings iteratively, adding in additional terms specific to each theory (e.g., "stabilizing niche differences" for Modern Coexistence Theory) in order to capture a substantial portion of the literature. Abstracts were screened to verify that the papers described direct empirical tests of the theory’s predictions (i.e., no meta-analyses or purely modelling papers). We retained 10 top-cited papers for each theory, for a total of 50 papers listed in the enclosed data file (equilibrium_conundrum_papers_final.csv. ## Description of the data and file structure The CSV file contains the following information: **Citation information:** Columns for "Publication Year", "Author(s)", "Title", "Journal", "Pages", "Issue", "Volume" **Which major ecological theory the paper tested ["Theory"]** mte = Metabolic Theory of Ecology (Brown et al. 2004) mct = Modern Coexistence Theory (Chesson 2000) metapopulation = Metapopulation Theory (Levins 1969) neutral = Unified Neutral Theory of Biodiversity (Hubbell 2001) R* = Tilman's Resource Ratio Theory (Tilman 1982) **Whether the equilibrium assumption is acknowledged ["Mentions equilibrium criterion?"]** yes/no **If equilibrium assumption is acknowledged, how the authors address it in their study ["How they engage with equilibrium"]** Modelling approach Verbally assumed Observed system or proxy variable at equilibrium Violation of equilibrium explains results