Lehrstuhl für Tierökologie und Tropenbiologie

Dr. Alice Claßen

Dr. Alice Claßen

Department of Animal Ecology and Tropical Biology
Biocenter, University of Würzburg
Am Hubland
97074 Würzburg
Raum: C044
Telefon: +49 931 31-82793

  • Ecological and evolutionary forces shaping the functional and phylogenetic diversity of insects along elevational gradients
  • macroecology
  • tropical plant-pollinator interaction networks
  • Ecosystem service capacity of pollinators

Ongoing research projects

beta4: Enhancing the structural diversity between patches for improving multidiversity and multifunctionality in production forests (FOR5375:). SP6: Plant-Animal Interactions - pollination, parasitism and seed dispersal (PI, together with Ingolf Steffan-Dewenter & Heike Feldhaar)

Alice Claßen (PI), Ingolf Steffan-Dewenter (PI), Clàudia Massó (PhD), Markus Meißner (Master), Annika Klein (Master), Anjelica Scherer (Bachelor)


ADaptation of Alpine Pollinators in Times of Global Change (ADAPT)

Junior research group in the Bavarian climate research network ("Bayerischen Klimaforschungsnetzwerk (bayklif)")


Alice Claßen (PI), Anne Fabienne Maihoff (PhD), Janika Kerner (PhD)



Kristof Brenzinger (Postdoc)

Nikki Sauer (Master student)

Peter Väth (TA)

Manuel Kuhn (Bachelor student)

Simon Schoger (Bachelor student)

Lukas Bofinger (Master student)

Irina Schemm (Bachelor student)

Elisa Treffehn (Bachelor student)

Simone Sahler (Bachelor student)

Katharina Kallnik (TA)


The research group ADAPT

ADAPT investigates how pollinators respond to climatic changes. We explore this at different levels of biological organization, i.e. from a molecular level up to the communtiy level.

Our main research questions are:

(1) How did pollinator communities in the national park Berchtesgaden change along elevational gradients within the last 10 years?

(2) Do pollinators that strongly respond to climatic changes share certain traits?

(3) How do bumblebee colonies perform in different climate and how do they respond to a climatic changes?

(4) What is the molecular basis of thermal adaptation in Bombus lucorum?

(5) How does land use impact the adaptation capacity of pollinator species?


Kilimanjaro Project SP7Effects of climate und land use change on biodiversity and ecosystem functioning of pollinators and decomposers

Alice ClaßenIngolf Steffan-Dewenter

  • Seit 2018 Leader of the junior research group "ADaptation of Alpine Pollinators in Times of global change" (ADAPT). University of Würzburg, Germany. 
  • 2015 - 2017 Postdoc at the University of Würzburg, Germany. Project: KiLi Sub Project 7: Effects of climate und land use change on biodiversity and ecosystem functioning of pollinators and decomposers
  • 2015: 6 months full-time partental leave (back in part time position) 
  • 2010-2014 PhD student at the University of Würzburg, Germany. Project: KiLi Sub Project 7: Effects of climate und land use change on biodiversity and ecosystem functioning of pollinators and decomposers
  • 2009 Diploma thesis in the population genetics group of the Dep. of Entomology, Max-Planck-Institute for Chemical Ecology, Jena (Germany). Subject: “On the trail of evolution: Which factors cause intraspecific variation in the sex pheromone of heliothine moths?”
  • 2008 field research on heliothine moths in North Carolina State University, Dept. Entomology, 3107 Gardner Hall, Raleigh, NC.
  • 2007 voluntary work in the cloud and rain forest of South America, Jatun Sacha Foundation, Ecuador.
  • 2004-09 Studies in Biology (majored in ecology) at the Free University of Berlin, Germany.

2023[ to top ]
  • Dzekashu FF, Pirk CWW, Yusuf AA, Classen A, Kiatoko N, Steffan-Dewenter I, Peters MK, Lattorff HMG (2023) Seasonal and elevational changes of plant-pollinator interaction networks in East African mountains. Ecology and Evolution 13: e10060.
  • Maihoff F, Friess N, Hoiss B, Schmid-Egger C, Kerner J, Neumayer J, Hopfenmüller S, Bässler C, Müller J, Classen A (2023) Smaller, more diverse and on the way to the top: Rapid community shifts of montane wild bees within an extraordinary hot decade. Diversity and Distributions 29: 272-288.
  • Maihoff F, Sahler S, Schoger S, Brenzinger K, Kallnik K, Sauer N, Bofinger L, Schmitt T, Nooten SS, Classen A (2023) Cuticular hydrocarbons of alpine bumble bees (Hymenoptera: Bombus) are species-specific, but show little evidence of elevation-related climate adaptation. Frontiers in Ecology and Evolution 11.
  • Müller J, Mitesser O, Cadotte MW, van der Plas F, Mori AS, Ammer C, Chao A, Scherer-Lorenzen M, Baldrian P, Bässler C, Biedermann P, Cesarz S, Claßen A, Delory BM, Feldhaar H, et al. (2023) Enhancing the structural diversity between forest patches—A concept and real-world experiment to study biodiversity, multifunctionality and forest resilience across spatial scales. Global Change Biology 29: 1437-1450.
2022[ to top ]
  • Brenzinger K, Maihoff F, Peters MK, Schimmer L, Bischler T, Classen A (2022) Temperature and livestock grazing trigger transcriptome responses in bumblebees along an elevational gradient. iScience 25: 105175.
  • Kerner JM, Krauss J, Maihoff F, Bofinger L, Classen A (2022) Alpine butterflies want to fly high: Species and communities shift upwards faster than their host plants. Ecology.
  • Moreaux C, Meireles DA, Sonne J, Badano EI, Classen A, González-Chaves A, Hipólito J, Klein A-M, Maruyama PK, Metzger JP, Philpott SM, Rahbek C, Saturni FT, Sritongchuay T, Tscharntke T, et al. (2022) The value of biotic pollination and dense forest for fruit set of {Arabica} coffee: {A} global assessment. Agriculture, Ecosystems & Environment 323: 107680.
  • Müller J, Scherer-Lorenzen M, Ammer C, Eisenhauer N, Seidel D, Schuldt B, Biedermann P, Schmitt T, Künzer C, Wegmann M, Cesarz S, Peters M, Feldhaar H, Steffan-Dewenter I, Claßen A, et al. (2022) BETA-FOR: Erhöhung der strukturellen Diversität zwischen Waldbeständen zur Erhöhung der Multidiversität und Multifunktionalität in Produktionswäldern. Antragstext für die DFG Forschungsgruppe FOR 5375. In.
  • Nevo O, Cazetta E, Classen A, Kuppler J (2022) Editorial: Anthropogenic stressors and animal-plant interactions: Implications for pollination and seed dispersal. Frontiers in Ecology and Evolution 10.
  • Sponsler D, Kallnik K, Requier F, Classen A, Maihoff AF, Sieger J, Steffan-Dewenter I (2022) Floral preferences of mountain bumble bees are constrained by functional traits but flexible through elevation and season. Oikos: e08902.
  • Sponsler DB, Requier F, Kallnik K, Classen A, Maihoff F, Sieger J, Steffan-Dewenter I (2022) Contrasting patterns of richness, abundance, and turnover in mountain bumble bees and their floral hosts. Ecology: e3712.
  • Welti EAR, Zajicek P, Frenzel M, Ayasse M, Bornholdt T, Buse J, Classen A, Dziock F, Engelmann RA, Englmeier J, Fellendorf M, Förschler MI, Fricke U, Ganuza C, Hippke M, et al. (2022) Temperature drives variation in flying insect biomass across a {German} malaise trap network. Insect Conservation and Diversity 15: 168-180.
  • Ziegler A, Meyer H, Otte I, Peters MK, Appelhans T, Behler C, Böhning-Gaese K, Classen A, Detsch F, Deckert J, Eardley CD, Ferger SW, Fischer M, Gebert F, Haas M, et al. (2022) Potential of Airborne LiDAR Derived Vegetation Structure for the Prediction of Animal Species Richness at Mount Kilimanjaro. Remote Sensing 14: 786.
2021[ to top ]
  • Albrecht J, Peters MK, Becker JN, Behler C, Classen A, Ensslin A, Ferger SW, Gebert F, Gerschlauer F, Helbig-Bonitz M, Kindeketa WJ, Kühnel A, Mayr AV, Njovu HK, Pabst H, et al. (2021) Species richness is more important for ecosystem functioning than species turnover along an elevational gradient. Nature Ecology & Evolution.
2020[ to top ]
  • Classen A, Eardley CD, Hemp A, Peters MK, Peters RS, Ssymank A, Steffan‐Dewenter I (2020) Specialization of plant–pollinator interactions increases with temperature at Mt. Kilimanjaro. Ecology and Evolution 10: 2182-2195.
  • Peters MK, Classen A, Müller J, Steffan-Dewenter I (2020) Increasing the phylogenetic coverage for understanding broad-scale diversity gradients. Oecologia 192: 629-639.
2019[ to top ]
  • Dainese M, Martin EA, Aizen MA, Albrecht M, Bartomeus I, Bommarco R, Carvalheiro LG, Chaplin-Kramer R, Gagic V, Garibaldi LA, Ghazoul J, Grab H, Jonsson M, Karp DS, Kennedy CM, et al. (2019) A global synthesis reveals biodiversity-mediated benefits for crop production. Science advances 5: eaax0121.
  • Maas B, Heath S, Grass I, Cassano C, Classen A, Faria D, Gras P, Williams-Guillén K, Johnson M, Karp DS, Linden V, Martínez-Salinas A, Schmack JM, Kross S (2019) Experimental field exclosure of birds and bats in agricultural systems — {Methodological} insights, potential improvements, and cost-benefit trade-offs. Basic and Applied Ecology 35: 1-12.
  • Peters MK, Hemp A, Appelhans T, Becker JN, Behler C, Classen A, Detsch F, Ensslin A, Ferger SW, Frederiksen SB, Gebert F, Gerschlauer F, Gütlein A, Helbig-Bonitz M, Hemp C, et al. (2019) Climate–land-use interactions shape tropical mountain biodiversity and ecosystem functions. Nature 568: 88-92.
2018[ to top ]
  • Albrecht J, Classen A, Vollstädt MGR, Mayr A, Mollel NP, Schellenberger Costa D, Dulle HI, Fischer M, Hemp A, Howell KM, Kleyer M, Nauss T, Peters MK, Tschapka M, Steffan-Dewenter I, et al. (2018) Plant and animal functional diversity drive mutualistic network assembly across an elevational gradient. Nature Communications 9: 3177.
  • Groot AT, Nojima S, Heath JJ, Ammagarahalli B, van Wijk M, Classen A, Santangelo RG, Lopez J, Schal C (2018) Alcohol Contributes to Attraction of Heliothis (= Chloridea) virescens Males to Females. Journal of Chemical Ecology 44: 621-630.
  • Nojima S, Classen A, Groot AT, Schal C (2018) Qualitative and quantitative analysis of chemicals emitted from the pheromone gland of individual Heliothis subflexa females. PLOS ONE 13: 1-13.
2017[ to top ]
  • Classen A, Steffan‐Dewenter I, Kindeketa WJ, Peters MK (2017) Integrating intraspecific variation in community ecology unifies theories on body size shifts along climatic gradients. Functional Ecology 31: 768-777.
  • Schellenberger Costa D, Classen A, Ferger S, Helbig-Bonitz M, Peters M, Böhning-Gaese K, Steffan-Dewenter I, Kleyer M (2017) Relationships between abiotic environment, plant functional traits, and animal body size at Mount Kilimanjaro, Tanzania. PloS one 12: e0174157.

Peters MK, Hemp A, Appelhans T, Behler C, Classen A, Detsch F, Ensslin A, Ferger SW, Frederiksen SB, Gebert F, Haas M, Helbig-Bonitz M, Hemp C, Kindeketa WJ, Mwangomo E, Ngereza C, Otte I, Röder J, Rutten G, Schellenberger Costa D, Tardanico J, Zancolli G, Deckert J, Eardley CD, Peters RS, Rödel M-O, Schleuning M, Ssymank A, Kakengi V, Zhang J, Böhning-Gaese K, Brandl R, Kalko EKV, Kleyer M, Nauss T, Tschapka M, Fischer M, Steffan-Dewenter I (2016). Predictors of elevational biodiversity gradients change from single taxa to the multi-taxa community level. Nature Communications 7: 13736. 

Classen A, Peters MK, Kindeketa WJ, Appelhans T, Eardley C, Gikungu MW, Hemp A, Nauss T, and Steffan-Dewenter I (2015) Temperature versus resource constraints: which factors determine bee diversity on Mt. Kilimanjaro, Tanzania? Global Ecology and Biogeography 24: 642-652. 

Classen A, Peters MK, Ferger SW, Helbig-Bonitz M, Schmack JM, Maassen G, Schleuning M, Kalko EKV, Böhning-Gaese K, and Steffan-Dewenter I (2014). Complementary ecosystem services provided by pest predators and pollinators increase quanitity and quality of coffee yields. Proceedings of the Royal Society B 281: 20133148.

Groot AT, Schöfl G, Inglis O,Donnerhacke S, Classen A, Schmalz A, Santangelo RG, Emerson J, Gould F, Schal C, and Heckel DG (2014). Within-population variability in a moth sex phermone blend: genetic basis and behavioural consequences. Proceedings of the Royal Society B 281: 20133054.

Groot AT,  Classen A, Inglis O, Blanco CA,  Lopez J Jr, Vargas AT, Schal C, Heckel DG and Schoefl G (2011). Genetic differentiation across North America in the generalist moth Heliothis virescens and the specialist H. subflexaMolecular Ecology 20: 2676-2692.

Groot AT, Classen A, Staudacher H, Schal C, and Heckel DG (2010). Phenotypic plasticity in sexual communication signal of a noctuid moth. Journal of Evolutionary Biology 23: 2731-2738.

Groot AT, Blanco CA, Classen A, Inglis O, Santangelo RG, Lopez J Jr, Heckel DG and Schal C (2010). Variation in Sexual Communication of the Tobacco Budworm, Heliothis virescens. Southwestern Entomologist 35: 367-372.