Theory & Methods of Ecology

I am very interested in theory of ecology, or rather conceptual ecology (e.g. terminology and conceptual frameworks). Also, I am interested in how ecology works as a science, and whether there are ways for improvement. In my point of view, ecology could profit much from a closer integration of single-study results into theory, and from closer interaction with other fields like computer sciences and philosophy.

Together with Jonathan Jeschke, I developed the hierarchy-of-hypotheses (HoH) approach, and us and several colleagues applied it to uncover the level of empirical evidence for major hypotheses in invasion ecology. At hi-knowledge.org, the result are summarized in a hierarchical network. It is our vision that if combined with natural language processing and other techniques, this web tool could be developed into an interactive atlas of knowledge for invasion ecology. Similar tools could be developed in other fields as well, e.g. restoration ecology or urban ecology.

Philosophy of science in my point of view offers a wealth of knowledge and methods we as ecologists could draw from for improving how we do our science. I am very interested in exploring these possibilities, and found out that philosophers often are highly interested in interacting with ecologists (see this publication; the same holds for computer scientists). As convener of a Focus Group at ZiF in Bielefeld, I worked together in an interdisciplinary team to explore possibilities for Mapping Evidence to Theory in Ecology. This work is ongoing (currently unfunded) under the header EcoWeaver (updates to follow soon).

Projects

AQUANAVI - Navigating Grand Challenges and their Mitigation using Aquatic Experimental Research Infrastructures (RIs)

Critical environmental challenges affect aquatic ecosystems worldwide, and the need to coordinate research efforts is increasingly urgent. Mesocosms are key Research Infrastructures (RIs) allowing the study of highly complex environments comparable to natural ecosystems. Mesocosm experiments, which offer controlled yet realistic settings, are crucial for understanding and mitigating the impact of various stressors and their combinations on aquatic ecosystems. The AQUACOSM-RI consortium, comprising over 60 individual state-of-the-art mesocosm facilities at 28 host institutions across Europe, has therefore been instrumental in advancing aquatic environmental research across climate zones including marine, brackish and freshwater ecosystems.

The AQUANAVI project (Navigating Grand Challenges and their Mitigation using Aquatic Experimental RIs) aims to create an interactive atlas of aquatic mesocosm-based experimental research. Data, publications, reports and information generated by the AQUACOSM consortium and other mesocosm facilities worldwide will be integrated into a single, accessible platform incorporating Open Knowledge Maps' AI-driven visual discovery tools. The project will foster collaborations and, by enhancing data FAIRness, it will facilitate fast discovery and efficient use of aquatic RIs globally, accelerating the development of environmental mitigation strategies.

More info here: AQUANAVI in nutshell video; Website at OSCARS; OSCARS-Meeting Rome 2025

Funded through EU-funded project OSCARS, since 2024

Project partners: Jonathan Jeschke, Stella A. Berger, Christopher Kittel, Peter Kraker, Katharina Makower, Daniel Mietchen, Jens Christian Nejstgaard, Maxi Schramm, Steph Tyszka

enKORE - Towards an open, zoomable atlas for invasion science and beyond

Invasive species and other non-native species are on the rise, and their global impacts on ecosystems, economies and human health are highly problematic. Invasion science, the study of these species, is critical to mitigate their impacts, yet due to the strong increase of data and information in this area, it has become difficult to acquire and maintain an overview of the field. As a result, existing evidence is often not found, knowledge is not transferred to practice, and research is conducted in pursuit of dead ends. We propose to address these challenges by developing an interactive atlas of invasion science that can be extended to other disciplines in the future. This knowledge portal will be called enKORE, EvolviNg KnOwledge REsource. It will be open for anyone to use, including researchers, citizen scientists, practitioners and policy makers. Users will be able to zoom into the major research questions and hypotheses of invasion science, which are connected to the relevant studies published in the field and, if available, the underlying raw data. enKORE will apply cutting-edge visualization techniques, artificial intelligence and novel methods for knowledge synthesis.

Funded by Volkswagen Foundation, project start: 2021 - 2024, project proposal

Project partners: Jonathan Jeschke, Peter Kraker, Daniel Mietchen

INAS - Interactive Argumentation Support in the Invasion Biology Domain

This project is funded as part of the Robust Argumentation Machines program by the DFG. We will develop an argumentation machine that supports users in and during the argumentation process in a scientific context. The goal is to enable users to follow ongoing argumentation in a scientific community and to develop their own arguments. The project collaborates closely with other initiatives that work on mapping and organizing scientific knowledge, such as the hi-knowledge project. Our interdisciplinary team brings together people from Natural Language Processing, Biology, Semantic Web and Knowledge Representation. Check out our project website!

Funded by DFG, project start: 2021 - 2025, project proposal

Project partners: Sina Zarrieß, Birgitta König-Ries, Jonathan Jeschke, Alsayed Algergawy

Essays

Lenzen, M. (2025): Episode #17: Using New Methods to Support Interdisciplinary Collaboration - with Tina Heger, Nora Pfützenreuter and Oliver Szasz. Podast Series InterSpaces, ZiF Bielefeld. [link]

Neuman,, N. (2025): „Der Begriff des Anthropozän bringt uns im Umweltschutz nicht weiter“. Interview mit Tina Heger. [link]

Jeschke, J., Bartram, I., Heger, T., Lokatis, S. & Tockner, K. (2020): Dark Knowledge ans Licht holen. Laborjournal 7-8: 34-37. [link to pdf]

Publications

* D'Souza, J., Al Mustafa, T., Auer, D. F., Bachinger, S. T., Brinner, M., Daniel, C., Das, N., Espig, A., Fathallah, N., Gow-Smith, E., Gunreben, L., Heider, N., Jadhav, H., Jalloul, B., Kommineni, V. K., Korani, S., Krutsylo, A., Ling, Z., Mendu, V., Miao, S., Ortiz Viso, B., Peter, A., Plenz, M., Razavian, J., Sherwani, M. K., Sharear Shopnil, M. N., Woof, W., Koenig-Ries, B., & Heger, T. (2025): Reflections from the 2025 EcoHack:  AI & LLM hackathon for applications in evidence-based ecological research & practice. EcoEvoRxiv. https://doi.org/10.32942/X2XP7J

Yannelli, F. A., Dawson, W., van Kleunen, M., Jeschke, J. M., & Heger, T. (2025): Hypothesis Description: Darwin’s Naturalisation Hypothesis [10.3897/rio.11.e140548]. Research Ideas and Outcomes, 11, e140548. https://doi.org/10.3897/rio.11.e140548

Staples, T. L., Blois, J., Cramer, K. L., Cunningham, E. T., Dornelas, M., Haberle, S. G., Heger, T., Kiessling, W., Magurran, A. E., O'Dea, A., Penny, A. M., Radeloff, V. C., Smith, J. A., Thuiller, W., Williams, J. W., & Pandolfi, J. M. (2025): A Conceptual Framework for Measuring Ecological Novelty. Global Ecology and Biogeography, 34(2), e70005. https://doi.org/10.1111/geb.70005

Heger, T., Elliot-Graves, A., Kaiser, M. I., Morrow, K. H., Bausman, W., Dietl, G. P., Dormann, C. F., Gibson, D. J., Griesemer, J., Itescu, Y., Jax, K., Latimer, A. M., Liu, C., Starrfelt, J., Stephens, P. A., & Jeschke, J. M. (2025): Looking beyond Popper: how philosophy can be relevant to ecology. Oikos,2025, e10994. https://doi.org/10.1111/oik.10994. Editor’s choice.

Musseau, C. L., Bernard-Verdier, M., Heger, T., Skopeteas, L. H., Strasiewsky, D., Mietchen, D., & Jeschke, J. M. (2024): A conceptual classification scheme of invasion science. BioScience, 74(12), 840-850. https://doi.org/10.1093/biosci/biae093

* Mietchen, D., Jeschke, J. M., Bernard-Verdier, M., Heger, T., Musseau, C., & Tyska, S. (2024): Invasion biology corpus 2024 [Data set]. https://doi.org/10.5281/zenodo.12518037

Heger, T., Algergawy, A., Brinner, M., Jeschke, J. M., König-Ries, B., Mietchen, D., Zarrieß, S. (2024): Natural language hypotheses in scientific papers and how to tame them. In: P. Cimiano, A. Frank, M. Kohlhase, B. Stein, Robust Argumentation Machines. RATIO 2024. Lecture Notes in Computer Science, pp. 3-19. Springer Nature Switzerland. https://doi.org/10.1007/978-3-031-63536-6_1

Brinner, M., Zarrieß, S., Heger, T. (2024): Weakly supervised claim localization in scientific abstracts. In: P. Cimiano, A. Frank, M. Kohlhase, B. Stein, Robust Argumentation Machines. RATIO 2024. Lecture Notes in Computer Science, pp. 20-38. Springer Nature Switzerland. https://doi.org/10.1007/978-3-031-63536-6_2

* Bernard-Verdier, M., Fadel, K., Heger, T., Jeschke, J. M., Stocker, M., Vogt, L. (2024): Knowledge synthesis in Invasion Biology: from a prototype to community-designed templates. In: S. Auer, V. Ilangovan, M. Stocker, S. Tiwari, L. Vogt (Eds.), Open Research Knowledge Graph, pp. 105-115. Cuvillier. https://cuvillier.de/get/ebook/6951/9783689420039_eBook.pdf

* Heger, T., Algergawy, A., Bernard-Verdier, M., Brinner, M. F., Jeschke, J. M., König-Ries, B., Mietchen, D., Musseau, C., Zarrieß, S. (2024): Summary report of the 3rd INAS-enKORE Workshop "Taming complexity in ecology: Novel approaches for theory development, enhanced argumentation and knowledge synthesis". Zenodo. https://doi.org/10.5281/zenodo.10997726

Heger, T., Jeschke, J. M., Bernard-Verdier, M., Musseau, C. L., Mietchen, D. (2024): Hypothesis Description: Enemy Release Hypothesis. Research Ideas and Outcomes, 10: e107393. https://doi.org/10.3897/rio.10.e107393

* Heger, T., Mietchen, D., Jeschke, J. M. (2024): Template for a Hypothesis Description paper. Research Ideas and Outcomes, 10: e119808. https://doi.org/10.3897/rio.10.e119808

* Mietchen, D., Jeschke, J. M., Heger, T. (2024): Introducing Hypothesis Descriptions. Research Ideas and Outcomes, 10, e119805. https://doi.org/10.3897/rio.10.e119805

* Bernard-Verdier, M., Heger, T., Mietchen, D., Musseau, C. L., Brinner, M., Hillig, A., Kraker, P., Lokatis, S., Nunes, A. L., Scheidweiler, N., Stocker, M., Vial, R., Vogt, L., Bacher, S., Baklouti, E., Gupta, H. B., Beisel, J.-N., Bertolino, S., Briski, E., Castellanos-Galindo, G. A., Courchamp, F., Daly, E., Dawson, W., Dickey, J., Evans, T., Itescu, Y., Koenig-Ries, B., Kumar, L., Kumschick, S., Meyerson, L. A., Pattison, Z., Pfadenhauer, W., Renault, D., Rickowski, F., Ruland, F., Schittko, C., Straka, T., Yannelli, F., Jeschke, J. M. (2023): Building an atlas of knowledge for invasion biology and beyond! 2nd enKORE-INAS Workshop. Research Ideas and Outcomes 9. https://doi.org/10.3897/rio.9.e115395

* Bernard-Verdier, M., Heger, T., Jeschke, J. M., Mietchen, D., Musseau, C. (2023): Summary report of the 1st enKORE-INAS workshop. In: Zenodo. https://doi.org/10.5281/zenodo.8421054

Lokatis, S., Jeschke, J. M., Bernard-Verdier, M., Buchholz, S., Grossart, H.-P., Havemann, F., Hölker, F., Itescu, Y., Kowarik, I., Kramer-Schadt, S., Mietchen, D., Musseau, C., Planillo, A., Schittko, C., Straka, T., Heger, T. (2023): Hypotheses in urban ecology: building a common knowledge base. Biological Reviews 98, 1530-1547. DOI: 10.1111/brv.12964

Daly, E. Z., Chabrerie, O., Massol, F., Facon, B., Hess, M. C. M., Tasiemski, A., Grandjean, F., Chauvat, M., Viard, F., Forey, E., Folcher, L., Buisson, E., Boivin, T., Baltora-Rosset, S., Ulmer, R., Gibert, P., Thiébaut, G., Pantel, J. H., Heger, T., Richardson, D. M., Renault, D. (2023): A synthesis of biological invasion hypotheses associated with the introduction–naturalisation–invasion continuum. Oikos 2023: e09645. DOI: 10.1111/oik.09645

Brinner, M., Heger, T., Zarriess, S. (2022): Linking a Hypothesis Network From the Domain of Invasion Biology to a Corpus of Scientific Abstracts: The INAS Dataset. In: Proceedings of the first Workshop on Information Extraction from Scientific Publications. Association for Computational Linguistics, pp. 32-42. [link to pdf]

Synodinos, A. D., Karnatak, R., Aguilar-Trigueros, C. A., Gras, P., Heger, T., Ionescu, D., Maaß, S., Musseau, C. L., Onandia, G., Planillo, A., Weiss, L., Wollrab, S., Ryo, M. (2023): The rate of environmental change as an important driver across scales in ecology. Oikos 2023: e09616. DOI: 10.1111/oik.09616

* Algergawy, A., Gänßinger, M., Heger, T., Jeschke, J., & König-Ries, B. (2022): The Invasion Biology Ontology (INBIO) [Data set]. Zenodo. DOI: 10.5281/zenodo.6826848

Heger, T., Jeschke, J. M., Febria, C., Kollmann, J., Murphy, S., Rochefort, L., Shackelford, N., Temperton, V.M., Higgs, E. (2022): Mapping and assessing the knowledge base of ecological restoration. Restoration Ecology. DOI: 10.1111/rec.13676; Blogpost with summary

Stocker, M., Heger, T., Schweidtmann, A.M., Ćwiek-Kupczyńska, H., Penev, L., Dojchinovski, M., Willighagen, E., Vidal, M.-E., Turki, H.A., Balliet, D., Tiddi, I., Kuhn, T., Mietchen, D., Karras, O., Vogt, L., Hellmann, S., Jeschke, J.M., Krajewski, P., Auer, S. (2022): SKG4EOSC - Scholarly Knowledge Graphs for EOSC: Establishing a backbone of knowledge graphs for FAIR Scholarly Information in EOSC. Research Ideas and Outcomes 8: e83789. DOI: 10.3897/rio.8.e83789 [link to pdf]

Heger, T. (2022): What are ecological mechanisms? Suggestions for a fine-grained description of causal mechanisms in invasion ecology. Biology & Philosophy 37:9. DOI: 10.1007/s10539-022-09838-1 [link to pdf]

Heger, T., Zarrieß, S., Algergawy, A., Jeschke, J.M. & König-Ries, B. (2022): INAS: Interactive Argumentation Support for the Scientific Domain of Invasion Biology. Research Ideas and Outcomes, 8, e80457. DOI: 10.3897/rio.8.e80457 [link to pdf]

Jeschke, J.M., Heger, T., Kraker, P., Schramm, M., Kittel, C. & Mietchen, D. (2021). Towards an open, zoomable atlas for invasion science and beyond. NeoBiota, 68: 5-18. DOI: 10.3897/neobiota.68.66685 [link to pdf]

Heger, T. (2021). Philosophy of Science for Biologists, edited by K. Kampourakis & T. Uller, Cambridge University Press (2020). 340pp., €33,20 (Paperback), ISBN: 9781108740708. Basic and Applied Ecology, 56: 176-177. DOI: 10.1016/j.baae.2021.07.012

Heger, T., Aguilar, C., Bartram, I., Braga, R. R., Dietl, G. P., Enders, M., Gibson, D. J., Gómez-Aparicio, L., Gras, P., Jax, K., Lokatis, S., Lortie, C. J., Mupepele, A.-C., Schindler, S., Starrfelt, J., Synodinos, A. & Jeschke, J. M. (2021): The hierarchy-of-hypotheses approach: A synthesis method for enhancing theory development in ecology and evolution. BioScience 71: 337-349. DOI: 10.1093/biosci/biaa130 [link to pdf]

Algergawy, A., Stangneth, R., Heger, T., Jeschke, J. M. & König-Ries, B. (2020): Towards a Core Ontology for Hierarchies of Hypotheses in Invasion Biology. The Semantic Web. ESWC 2020 Satellite Events (LNCS Series). [link to pdf]

Enders, M., Havemann, F., Ruland, F., Bernard-Verdier, M., Catford, J. A., Gómez Aparicio, L., Haider, S., Heger, T., Kueffer, C., Kühn, I., Meyerson, L. A., Musseau, C., Novoa, A., Ricciardi, A., Sagouisa, A., Schittko, C., Strayer, D. L., Vilà, M., Essl, F., Hulme, P. E., van Kleunen, M., Kumschick, S., Lockwood, J. L., Mabey, A., McGeoch, M. A., Palma, E., Pyšek, P., Saul, W.-C., Yannelli, F. & Jeschke, J. M. (2020): A conceptual map of invasion biology: integrating hypotheses into a consensus network. Global Ecology and Biogeography 29: 978-991. DOI: 10.1111/geb.13082 [link to pdf]

Ryo, M., Jeschke, J. M., Rillig, M. & Heger, T. (2020): Machine learning with the hierarchy-of-hypotheses (HoH) approach discovers novel pattern in studies on biological invasions. Research Synthesis Methods 11: 66-73. DOI: 10.1002/jrsm.1363 [link to pdf]

Heger, T. & Jeschke, J. M. (2018): The hierarchy-of-hypotheses approach. –  Jeschke, J. M. & Heger, T. (eds). Invasion Biology. Hypotheses and Evidence. CAB International: 14-18.

Heger, T. & Jeschke, J. M. (2018): The hierarchy-of-hypotheses approach updated - a toolbox for structuring and analysing theory, research and evidence. –  Jeschke, J. M. & Heger, T. (eds). Invasion Biology. Hypotheses and Evidence. CAB International: 38-47.

Heger, T. & Jeschke, J. M. (2018): Enemy release hypothesis. –  Jeschke, J. M. & Heger, T. (eds). Invasion Biology. Hypotheses and Evidence. CAB International: 92-102.

Heger, T. & Jeschke, J. M. (2018): Conclusions and outlook. –  Jeschke, J. M. & Heger, T. (eds). Invasion Biology. Hypotheses and Evidence. CAB International: 167-172.

Jeschke, J. M. & Heger, T. (2018):  Synthesis. –  Jeschke, J. M. & Heger, T. (eds). Invasion Biology. Hypotheses and Evidence. CAB International: 157-166.

Heger, T. & Jeschke, J. M. (2014): The enemy release hypothesis as a hierarchy of hypotheses. Oikos 123: 741-750. DOI: 10.1111/j.1600-0706-2013.01263.x

Heger, T., Pahl, A. T., Botta-Dukát, Z., Gherardi, F., Hoppe, C., Hoste, I., Jax, K., Lindström, L., Boets, P., Haider, S., Kollmann, J., Wittmann, M. & Jeschke, J. M. (2013): Conceptual frameworks and methods for advancing invasion ecology. AMBIO 42: 527–540. DOI: 10.1007/s13280-012-0379-x

Heger, T., Saul, W.-C. & Trepl, L. (2013): What biological invasions 'are' is a matter of perspective. Journal for Nature Conservation 21: 93-96. DOI: 10.1016/j.jnc.2012.11.002

Jeschke, J. M., Gómez Aparicio, L., Haider, S., Heger, T., Lortie, C. J., Pyšek, P. & Strayer, D. L. (2012): Support for major hypotheses in invasion biology is uneven and declining. NeoBiota 14: 1-20. DOI: 10.3897/neobiota.14.3435 [link to pdf]