Dr Adam Thomas Clark

Scientific Guest

Research Interests


I am currently a postdoc working with Stan Harpole and Helmut Hillebrand at the German Centre for Integrative Biodiversity Research (iDiv) in Leipzig, Germany. I am broadly interested in how ecological communities persist across space and time. To me, the defining characteristic of ecological communities is that they self-assemble, and that they maintain themselves across large spatial and temporal scales even when faced with perturbations and disturbance. I find this fascinating because it suggests that predictive understanding of community ecology could help us engineer ecological communities that provide particular desired goods and services, but are able to maintain themselves with minimal inputs.

In order to address this topic, I work across many kinds of ecological communities, though I am particularly familiar with tallgrass prairies in the US Midwest, and ant communities in the US North East and the Caribbean. My work includes field experiments, taxonomy, and building new theoretical models. My main focus is on synthesizing existing data and theory (of which there is a lot) in order to build predictive models of community assembly for real-world systems, which remains an elusive goal in ecology.

Curriculum Vitae


A copy of my current CV is available here.

Scientific Education


1. Ph.D. 2011–2017
University of Minnesota Saint Paul, MN
Dept. Ecology, Evolution, and Behavior
Advisor: David Tilman

2. BA, cum laude 2007–2011
Harvard University Cambridge, MA
Major: Environmental Science and Public Policy
Advisor: Brian Farrell

Scientific Career


I finished my Ph.D. work in summer 2017, working under David Tilman in the University of Minnesota's Department of Ecology Evolution, and Behavior. My research was conducted predominantly at the Cedar Creek Long Term Ecological Research Site, and worked to explain how interactions among prairie plant species and their environments influenced ecosystem properties. I completed my undergraduate work at Harvard University's Museum of Comparative Zoology in 2011, studying the effects of disturbance on ant community assembly in the Brian Farrell Lab. During this time I also worked as an REU at Harvard Forest, supervised by Shannon Pelini and Israel Del Toro. Though I focus mostly on plant communities these days, but I'm still excited by projects that involve ant ecology and taxonomy.

Publications before iDiv


Adam T. ClarkConstraints and tradeoffs: Toward a predictive, mechanism-based understanding of ecological communities. Ph.D. Thesis, 2017. <link>HDL: hdl.handle.net/11299/191380

Adam T. Clark. "Old Fields". In Oxford Bibliographies in Ecology. Ed. David Gibson. New York: Oxford University Press, 2017. <link> <pdf> DOI: 10.1093/OBO/9780199830060-0188

Adam T. Clark, Matteo Detto, Helene C. Muller-Landau, Stefan A. Schnitzer, S. Joseph Wright, Richard Condit, and Stephen P. Hubbell. "Functional traits of tropical trees and lianas explain spatial structure across multiple scales". Journal of Ecology, 2017, in press. <pressrelease> <link> <pdf> <sup>DOI: 10.1111/1365-2745.12804

Richard Barnes and Adam T. Clark (authors contributed equally). "65 Million Years of Change in Temperature and Topography Explain Evolutionary History in Eastern North American Plethodontid Salamanders". American Naturalist 190(1), 2017. <pressrelease> <link> <pdf> <sup> DOI: 10.1086/691796

Jacob M. Jungers, Adam T. Clark, Kevin Betts, Margaret E. Mangan, Donald L. Wyse, and Craig C. Sheaffer. "Long-Term Biomass Yield and Species Composition in Native Perennial Bioenergy Cropping Systems". Agronomy Journal 107(5):1627-1640, 2015. <link> <pdf> DOI:10.2134/agronj15.0014

Adam T. Clark, H. Ye, Forest Isbell, Ethan R. Deyle, Jane Cowles, David Tilman, and George Sugihara. "Spatial ’convergent cross mapping’ to detect causal relationships from short time-series". Ecology 96(5) 1174-1181, 2015.  <link> <pdf> <sup> DOI: 10.1890/14-1479.1

Adam T. Clark, Jessica J. Rykken, and Brian D. Farrell. "The effects of biogeography on ant diversity and activity on the Boston Harbor Islands, Massachusetts, USA". PLOS ONE, 6(11), 2011. <link> <pdf>DOI: 10.1371/journal.pone.0028045

Ongoing Projects


Synthesis Centre of Biodiversity Sciences: Catalyst Postdoctoral Position 2017-2019

“sMultiMod: Synthesis of multiple predictive models of community composition and coexistence”

Salaried Position Two Years
Additional Research Funding €15768.88



Information about courses that I have taught, including lecture slides and notes, are available here.

Other professional activities


I. Scientific writing for general audiences:

1. The Graduate School Cookbook: One way to approach PhD applications in ecology <pdf> <github>
This document is a collection of thoughts on the graduate school application process that I've collected over the years from friends and colleagues. If you have any comments on items to add or change, please let me know, either through email, or through the Github page.

2. Press Release: Tropical trees, lianas, and spatial structure. Journal of Ecology, 2017. <link>

3. Press Release: Study uses models to peer into salamanders' pasts. American Naturalist, 2017. <link>

4. How to find a moose: intentions in phenomenological and mechanistic models. PLOS Ecology Blog, 2016. <link>

5. Blog for Job Opportunities in Ecology. Resource Modeling Association, 2015-2016. <link> 

II. Software packages

1. nondirfit: GitHub R project, Adam Clark 2015

2. rEDM: Software Tutorial, Hao Ye, Adam Clark, Ethan Deyle 2015

3. multispatialCCM: CRAN R package 2014

4. tilmanstability: GitHub R project 2013

III. Professional Affiliations

Ecological Society of America: Member since 2010

Society of American Naturalists: Member since 2016

IV.Peer reviews for journals:

Ecography, Ecological Indicators, Ecology, Ecology Letters, Environmental Conservation, Journal of Behavior, Journal of Theoretical Biology, Oikos, Pedobiologia, PLOS ONE

iDiv publications


A. T. Clark, J.-F. Arnoldi, Y. R. Zelnik, G. Barabas, D. Hodapp, C. Karakoç, S. König, V. Radchuk, I. Donohue, A. Huth, C. Jacquet, C. de Mazancourt, A. Mentges, D. Nothaaß, L. G. Shoemaker, F. Taubert, T. Wiegand, S. Wang, J. M. Chase, M. Loreau, S. Harpole

(2021): General statistical scaling laws for stability in ecological systems. Ecology Letters

Barry, K. E., G. A. Pinter, J. W. Strini, K. Yang, I. G. Lauko, S. A. Schnitzer, A. T. Clark, J. Cowles, A. S. Mori, L. Williams, P. B. Reich, A. J. Wright

(2021): A graphical null model for scaling biodiversity–ecosystem functioning relationships. Journal of Ecology

M. S. Crawford, K. E. Barry, A. T. Clark, C. E. Farrior, J. Hines, E. Ladouceur, J. W. Lichstein, I. Maréchaux, F. May, A. S. Mori, B. Reineking, L. A. Turnbull, C. Wirth, N. Rüger

(2021): The function-dominance correlation drives the direction and strength of biodiversity–ecosystem functioning relationships. Ecology Letters

P. Hofmann, A. Clark, P. Hoffmann, A. Chatzinotas, W. S. Harpole, S. Dunker

(2021): Beyond nitrogen: phosphorus – estimating the minimum niche dimensionality for resource competition between phytoplankton. Ecology Letters

Chen, Y., Huang, Y., Niklaus, P. A., Castro-Izaguirre, N., Clark, A. T., Bruelheide, H., Ma, K., Schmid, B.

(2020): Directed species loss reduces community productivity in a subtropical forest biodiversity experiment. Nature Ecology & Evolution

Clark, A. T., Ann Turnbull, L., Tredennick, A., Allan, E., Harpole, W. S., Mayfield, M. M., Soliveres, S., Barry, K., Eisenhauer, N., de Kroon, H., Rosenbaum, B., Wagg, C., Weigelt, A., Feng, Y., Roscher, C., Schmid, B.

(2020): Predicting species abundances in a grassland biodiversity experiment: Trade-offs between model complexity and generality. Journal of Ecology

Dietrich, P., Roscher, C., Clark, A. T., Eisenhauer, N., Schmid, B., Wagg, C.

(2020): Diverse plant mixtures sustain a greater arbuscular mycorrhizal fungi spore viability than monocultures after 12 years. Journal of Plant Ecology

Karakoç, C., Clark, A. T., Chatzinotas, A.

(2020): Diversity and coexistence are influenced by time-dependent species interactions in a predator–prey system. Ecology Letters

Lehman, C., Loberg, S., Clark, A. T., Schmitter, D.

(2020): Unifying the Basic Models of Ecology to Be More Complete and Easier to Teach. Bioscience

Mühlbauer, L. K., M. Schulze, W. S. Harpole, A. T. Clark

(2020): gauseR: Simple methods for fitting Lotka-Volterra models describing Gause’s “Struggle for Existence”. Ecology and Evolution

Virtanen, R., A. T. Clark, M. den Herder, H. Roininen

(2020): Dynamic effects of insect herbivory and climate on tundra shrub growth: Roles of browsing and ramet age. Journal of Ecology

Barry, K. E., H. de Kroon, P. Dietrich, W. Stanley Harpole, A. Roeder, B. Schmid, A. T. Clark, M. M. Mayfield, C. Wagg, C. Roscher

(2019): Linking local species coexistence to ecosystem functioning: A conceptual framework from ecological first principles in grassland ecosystems. In: Nico Eisenhauer, David A. Bohan, Alex J. Dumbrell (Eds.) Mechanisms underlying the relationship between biodiversity and ecosystem function Advances in Ecological Research

Catford, J. A., Smith, A. L., Wragg, P. D., Clark, A. T., Kosmala, M., Cavender-Bares, J., Reich, P. B., Tilman, D.

(2019): Traits linked with species invasiveness and community invasibility vary with time, stage and indicator of invasion in a long-term grassland experiment. Ecology Letters

Clark, A. T., Barry, K. E., Roscher, C., Buchmann, T., Loreau, M., Harpole, W. S.

(2019): How to Estimate Complementarity and Selection Effects from an Incomplete Sample of Species. Methods in Ecology and Evolution

Clark, A. T., H. Hillebrand, W. S. Harpole

(2019): Scale Both Confounds and Informs Characterization of Species Coexistence in Empirical Systems. The American Naturalist

Clark, A. T., Knops, J. M. H., Tilman, D.

(2019): Contingent factors explain average divergence in functional composition over 88 years of old field succession. Journal of Ecology

Isbell, F., Tilman, D., Reich, P. B., Clark, A. T.

(2019): Deficits of biodiversity and productivity linger a century after agricultural abandonment. Nature Ecology & Evolution

Clark, A. T., Neuhauser, C.

(2018): Harnessing uncertainty to approximate mechanistic models of interspecific interactions. Theoretical Population Biology

Sullivan, L. L., Clark, A. T., Tilman, D., Shaw, A. K.

(2018): Mechanistically derived dispersal kernels explain species-level patterns of recruitment and succession. Ecology

Thomas Clark, A., Lehman, C., Tilman, D.

(2018): Identifying mechanisms that structure ecological communities by snapping model parameters to empirically observed tradeoffs. Ecology Letters
Icon address

Puschstrasse 4
04103 Leipzig

Icon roomnumber


Icon institutes

Helmholtz Centre for Environmental Research – UFZ

Share this site on:
iDiv is a research centre of theDFG Logo