Eco-evolutionary responses of plants to spatial and temporal climatic variation Dissertation David E.V. Harter Eco-evolutionary responses of plants to spatial and temporal climatic variation Dissertation zur Erlangung des akademischen Grades Doctor rerum naturalium (Dr. rer. nat.) an der Fakultät für Biologie, Chemie und Geowissenschaften der Universität Bayreuth vorgelegt von David Edgar Vincens Harter geboren am 23. Januar 1980 in Berlin, Deutschland Bayreuth, im Juli 2015 Die vorliegende Arbeit wurde in der Zeit von Juli 2010 bis Juli 2015 in Bayreuth am Lehrstuhl für Biogeografie unter Betreuung von Herrn Professor Dr. Carl Beierkuhnlein angefertigt. Vollständiger Abdruck der von der Fakultät für Biologie, Chemie und Geowissenschaften der Universität Bayreuth genehmigten Dissertation zur Erlangung des akademischen Grades eines Doktors der Naturwissenschaften (Dr. rer. Nat.). Dissertation eingereicht am: 22.07.2015 Zulassung durch die Promotionskomission: 30.07.2015 Wissenschaftliches Kolloquium: 22.02.2016 Amtierender Dekan: Prof. Dr. Stefan Schuster Prüfungsausschuss: Prof. Dr. Carl Beierkuhnlein (Erstgutachter) Prof. Dr. Heike Feldhaar (Zweitgutachterin) Prof. Dr. Cyrus Samimi (Vorsitz) Prof. Dr. Thomas Köllner Drittgutachter: Prof. Dr. Frank Thomas i “… for the times they are a-changin'.” Bob Dylan, The Times They Are a-Changin' (1964) ii Cover page picture: The island of La Gomera as viewed from the Teno mountains on Tenerife in autumn 2010. iii Content Background and motivation ...................................................................................................................... 1 Structure of this thesis ............................................................................................................................... 3 Overview of eco-evolutionary responses to environmental variation .......................................... 7 Contemporary climatic changes and their impacts on plants ........................................................ 9 Temperature increase ............................................................................................................................. 9 Changes in precipitation patterns ................................................................................................... 10 Extreme events ........................................................................................................................................ 11 Interactions of climate change impacts with abiotic and biotic factors ............................... 12 Plants responding to climatic variation and change ........................................................................15 General aspects of environmental tolerance ..................................................................................15 Phenotypic plasticity ........................................................................................................................... 16 Transgenerational plasticity ...............................................................................................................18 Evolutionary adaptation ..................................................................................................................... 20 Dispersal and range shifts ...................................................................................................................24 Outlook ......................................................................................................................................................... 29 References .................................................................................................................................................... 33 Manuscripts of this thesis ....................................................................................................................... 45 Overview .................................................................................................................................................. 45 Declarations of own contributions to each manuscript ............................................................ 50 Manuscript 1 ........................................................................................................................................... 53 Manuscript 2 .......................................................................................................................................... 97 Manuscript 3 ......................................................................................................................................... 113 Manuscript 4 .........................................................................................................................................137 Manuscript 5 ........................................................................................................................................ 157 Manuscript 6 ........................................................................................................................................ 185 Summary ................................................................................................................................................... 209 Zusammenfassung .................................................................................................................................... 211 Acknowledgements ................................................................................................................................ 213 Declarations .............................................................................................................................................. 215 Appendix .................................................................................................................................................... 216 iv v Background and motivation Background and motivation Climate-related resources (water and energy) and their distribution and availability in space and time are crucial determinants of biogeographic and evolutionary histories of organisms. Organismal association and adaptation (see Box 1) to climatic parameters and their variation emerge over various spatial scales and organisational levels, from single genes and individuals, over populations, species and ecosystems to global biodiversity patterns, as well as from ecological (e.g. within single seasons) to long-term macro-evolutionary time scales (geological ages). Current organisms and their traits, as well as their spatial distributions and assemblages are the result of environmental pressures and opportunities in dynamic biogeographical settings from the past to present. Within the limits of specific phylogenetic constraints, populations evolve by numerous eco-evolutionary steps that potentially sum up to the formation of new species and phylogenetic lineages. While the entirety of processes like speciation is hardly discernible within a researcher’s lifetime, one can very well observe parts of the eco-evolutionary continuum. The study of species’ and populations’ ecological, evolutionary and biogeographical responses to changing environments is one of the most exciting topics in biology as it deals with an essential sign of life itself. Such snapshots of eco- evolutionary shifts thus provide invaluable insight into general processes in evolution and ecology. It is also crucial for the needed forecasts of global climate change outcomes. The current climatic change is increasingly affecting ecological and evolutionary developments of species and ecosystems (Parmesan 2006; Lavergne et al. 2010). Consequences for biodiversity patterns and for human wellbeing are already observable and will intensify in the future considering climate projections for the coming decades (Pereira et al. 2010; IPCC 2014a; Selwood et al. 2015). Currently, this has generated an unprecedented societal interest in modes, capacities and magnitudes of organismal responses to environmental change. In general, knowledge on adaptive variation to climatic parameters among populations and species on different spatial and temporal scales can bring valuable insights into their response capacities. Furthermore, drastic climatic changes are not exceptional but rather a reoccurring phenomenon in earth history. Taking references to past climate change outcomes can therefore be helpful in order to understand current processes when keeping in mind that the current anthropogenic climate change may not entirely be comparable to past climate shifts. The very rapid current pace of change demands for very fast responses, and many species may not be able to react with sufficient rapidity and efficacy (e.g. Jump & Peñuelas 2005; Urban et al. 2012; Manuscript 1). 1 Background and motivation Possible responses to climatic alterations include adaptive phenotypic reactions and evolutionary change, or dispersal (see Box 1) and range shifts following clines of suitable habitat. Global climate change is thus not only a challenge, but can be seen as an open-ended natural experiment, making it feasible to study different types of biotic reactions to environmental alterations. Nevertheless, the understanding of actual response capacities and underlying mechanisms, as well as of interactions with other factors of global change (e.g. land-use change, eutrophication, species invasions, biotic interactions) is still on an early stage. This thesis aims to improve knowledge of relevant ecological and evolutionary processes related to climatic change and variation. Several types