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More information about this series at http://www.springer.com/series/15408 Gerhard Zotz Plants on Plants – The Biology of Vascular Epiphytes Gerhard Zotz Institute of Biology and Environmental Sciences University of Oldenburg Oldenburg, Germany ISSN 2509-6745 ISSN 2509-6753 (electronic) Fascinating Life Sciences ISBN 978-3-319-39236-3 ISBN 978-3-319-39237-0 (eBook) DOI 10.1007/978-3-319-39237-0 Library of Congress Control Number: 2016951311 # Springer International Publishing Switzerland 2016 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. The publisher, the authors and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication. Neither the publisher nor the authors or the editors give a warranty, express or implied, with respect to the material contained herein or for any errors or omissions that may have been made. Cover illustration: Cover photo shows epiphytic Fascicularia bicolor in a temperate rainforest near Huinay (Chile), courtesy of Simon Pfanzelt Printed on acid-free paper This Springer imprint is published by Springer Nature The registered company is Springer International Publishing AG Switzerland Preface Epibiota, organisms which live on other living things, are a fascinating facet of life on earth. A barnacle on a blue whale, a tiny diatom on a huge kelp, a liverwort on a palm leaf in the understory of a rainforest, and a huge tank bromeliad in the outer crown of a giant tree have quite a few things in common, but there are also a large number of distinctions. My initial plan was to write a book with a very broad taxonomic scope, covering at least the phenomenon of epiphytism in terrestrial, i.e., non-marine and non-limnetic, systems. This would have resulted in the treatise of epiphytic vascular plants, lichens, mosses, liverworts, and (terrestrial) algae such as Trentepohlia sp. It took a few months for me to realize that covering the biology of vascular epiphytes in the desired depth would already be enough of a challenge for a single person. Hence, I narrowed the scope to the biology of the approximately 28,000 species of vascular plants which always or primarily occur on other plants. The reader will see that this does not mean, however, that I am ignoring nonvascular epiphytes or other canopy-living organisms. As much as possible, I tried to identify open research questions and to connect the particular case of vascular epiphytes to general biological principles, hoping that this will make stimulating reading both for the advanced graduate student, who is, e.g., looking for an interesting project, and for the senior scientist turning to epiphytes because there may be a connection with the organisms he or she is studying. The final product of my efforts may also be seen as the successor of a book that has been the reference for those with a genuine interest in vascular epiphytes for more than a quarter century, David H. Benzing’s seminal “Vascular epiphytes,” which was published in 1990. I can only hope that my book will be as stimulating and useful a resource as David’s book has been for me and many others for the last decades. Initially planning to write in “dry” scientific prose, I soon decided to include personal comments on desirable directions and to be rather explicit in pointing out particular areas that I consider understudied. A provocative statement here and there is arguably a way to stimulate interesting science. If you disagree about a particular point of view, let me know—and let’s start a discussion about the best way to move forward. Oldenburg, Germany Gerhard Zotz February 2016 v ThiS is a FM Blank Page Acknowledgments Science is a social endeavor. Hence, this single-author monograph is not the isolated achievement of one person but builds on the work of many others. I have tried to acknowledge this contribution of others with numerous citations, which in the end yielded a substantial citation list. However, it is simply impossible to cite all papers that contributed in one way or the other to this book in a comprehensive way. My personal collection of publications that contain information on vascular epiphytes sums up to almost 7000 papers, books, book chapters, theses, or reports. I apologize if your paper is not cited—I had to make a choice. This does not suggest any underlying judgment of quality or importance. In addition, I had countless conversations with colleagues and students on my favorite subject over the last two decades, which helped to form the ideas and conclusions of this book. I also use unpublished information. For example, Cat Cardelu´s (Colgate, USA), Michael Kessler (ETH, Switzerland), and Nico Bluthgen€ (Darmstadt, Germany) provided extensive datasets on nutrient concentrations. Wolfgang Wanek (Vienna, Austria) shared unpublished data on nutrient uptake and Peter Hietz (Vienna, Austria) unpublished biomass data. Finally, I thank Rhett Harrison (Kunming, PR China) for sharing insights into the biology of hemiepiphytes. A number of colleagues (Dirk Albach, Jose-Luis Andrade, Catherine Cardelu´s, Helena Einzmann, Peter Hietz, Michael Kessler, Holger Kreft, Thorsten Kromer,€ Glenda Mendieta Leiva, Heidi Meudt, Ana Silvia Moreira, Simon Pfanzelt, Alfredo Saldana,~ Katrin Wagner, and Wolfgang Wanek) read drafts of individual chapters and I am grateful for their suggestions and frank criticism. Others helped out with specific information on canopy anurans, euglossine bees, or C4 photosynthesis (Shawn McCracken, David Roubik, and Rowan Sage). Having said this, I am solely responsible for any factual mistakes or interpretations you may disagree with. I am happy to take any criticism. I thank Herta Sauerbrey (University Oldenburg) and Angel Aguirre (Smithsonian Tropical Research Institute—STRI) for all the help in procuring literature over many years. Dirk Albach, Peter Bak, Wilhelm Barthlott, Kevin Burns, Damian Catchpole, Gerhard Gottsberger, Michael Kessler, Moritz Klinghardt, Bejat McCracken, Ana Silvia Moreira, Steve Pearce, Rick Riefner, David Roubik, Steven Sylvester, and Christian Ziegler generously offered vii viii Acknowledgments photographs. Laura Kuijpers, Christian Konig,€ and Holger Kreft helped with the geographical data and the preparation of the global distribution figures. Katrin Wagner supplied modified versions of graphs of previous publications. Vera Mageney and Dirk Albach helped with the figure on the relationship of pseudobulbs, epiphytism, and phylogeny in the Epidendroideae. Joachim Beyschlag provided a graph illustrating the potential of Y-Plant. Last but not least, I also want to acknowledge the financial support by a number of institutions that made it possible for me to work on the biology of epiphytes for so many years, most prominently the DFG, but also the DAAD, STRI in Panama, the Jubila¨umsstiftung in Wurzburg,€ Germany, and the Freiwillige Akademische Gesellschaft in Basel, Switzerland. A Comment on Plant Names Accepted species names are not constant but rather frequently change with taxo- nomic revisions. For consistency, I only use names that are currently accepted in the online database “The Plant List” (accessed December 2015), even when other names were used in the original publications. The following list compares the currently accepted names with those in the original publications. Name used in original publication Currently valid name Family Didymopanax pittieri Schefflera rodriguesiana Araliaceae Epidendrum macrostachyum Beclardia macrostachya Orchidaceae Ficus stupenda Ficus crassiramea subsp. stupenda Moraceae Guzmania minor Guzmania lingulata Bromeliaceae Laelia cinnabarina Cattleya cinnabarina Orchidaceae Lecanopteris sinuosa Myrmecophila sinuosa Polypodiaceae Oncidium enderianum Oncidium praetextum Orchidaceae Pitcairnia flavescens Pitcairnia albiflos Bromeliaceae Pleopeltis polypoidoides Polypodium polypodioides Polypodiaceae Polypodium phvllitidis Campyloneurum phyllitidis Polypodiaceae Polypodium crassifolium Niphidium crassifolium Polypodiaceae Psygmorchis pusilla