Chimpanzees As Ecosystem Service Providers: Seed Dispersal of an Economically Important Plant Resource at Fongoli, Senegal William Aguado Iowa State University
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Iowa State University Capstones, Theses and Graduate Theses and Dissertations Dissertations 2018 Chimpanzees as ecosystem service providers: Seed dispersal of an economically important plant resource at Fongoli, Senegal William Aguado Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/etd Part of the Biological and Physical Anthropology Commons, Ecology and Evolutionary Biology Commons, and the Environmental Sciences Commons Recommended Citation Aguado, William, "Chimpanzees as ecosystem service providers: Seed dispersal of an economically important plant resource at Fongoli, Senegal" (2018). Graduate Theses and Dissertations. 16539. https://lib.dr.iastate.edu/etd/16539 This Thesis is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Chimpanzees as ecosystem service providers: Seed dispersal of an economically important plant resource at Fongoli, Senegal by William Dane Aguado A thesis submitted to the graduate faculty in partial fulfillment of the requirements for the degree of MASTER OF ARTS Major: Anthropology Program of Study Committee: Jill Pruetz, Co-Major Professor Maximilian Viatori, Co-Major Professor Haldre Rogers Stacy Lindshield The student author, whose presentation of the scholarship herein was approved by the program of study committee, is solely responsible for the content of this thesis. The Graduate College will ensure this thesis is globally accessible and will not permit alterations after a degree is conferred. Iowa State University Ames, Iowa 2018 Copyright © William Dane Aguado, 2018. All rights reserved. ii TABLE OF CONTENTS Page LIST OF FIGURES ............................................................................................................. iv LIST OF TABLES ................................................................................................................ v ACKNOWLEDGMENTS ................................................................................................... vi ABSTRACT ....................................................................................................................... vii CHAPTER 1. GENERAL INTRODUCTION ....................................................................... 1 Ecosystem Services and Seed Dispersal..................................................................... 1 Chimpanzee Seed Dispersal ...................................................................................... 5 Background on study system ..................................................................................... 6 Saba senegalensis .......................................................................................... 6 Fongoli Chimpanzees .................................................................................. 11 Goals ....................................................................................................................... 13 References............................................................................................................... 14 CHAPTER 2. CHIMPANZEES AS ECOSYSTEM SERVICE PROVIDERS: SEED DISPERSAL OF AN ECONOMICALLY IMPORTANT PLANT RESOURCE AT FONGOLI SENEGAL ........................................................................................................ 18 Abstract ................................................................................................................... 18 Introduction ............................................................................................................. 19 Methods .................................................................................................................. 25 Study Site and System .................................................................................. 25 Fongoli ............................................................................................. 25 Saba senegalensis ............................................................................ 26 Data Collection ............................................................................................ 27 Germination trials ............................................................................ 27 Germination success in situ .............................................................. 29 Analysis ....................................................................................................... 32 Patterns of seed dispersal.................................................................. 32 Germination trials ............................................................................ 33 Germination success in situ .............................................................. 34 Results .................................................................................................................... 36 Germination Trials ....................................................................................... 36 Germination success between seed conditions .................................. 36 Time to germination between seed conditions .................................. 37 Seed Dispersal In Situ .................................................................................. 37 Germination and establishment success in situ ................................. 38 Discussion ............................................................................................................... 40 Effectiveness of Gut Treatment .................................................................... 40 Chimpanzee-Dispersed Seeds In Situ ........................................................... 43 iii Seed dispersal patterns ..................................................................... 45 Effects on germination success in situ .............................................. 48 Relative importance of chimpanzees to Saba dispersal ..................... 50 Conclusion .............................................................................................................. 57 References............................................................................................................... 58 Tables ..................................................................................................................... 65 Figures .................................................................................................................... 73 CHAPTER 3. GENERAL CONCLUSION ......................................................................... 88 Limitations and future directions ............................................................................. 89 References............................................................................................................... 91 iv LIST OF FIGURES Page Figure 1.1 Location of Fongoli study site .............................................................................. 7 Figure 1.2 Saba senegalensis .............................................................................................. 10 Figure 1.3 Adult male chimpanzee ...................................................................................... 12 Figure 2.1 Experimental setup ............................................................................................. 73 Figure 2.2 Seed germination by time ................................................................................... 74 Figure 2.3 Map of seed dispersal events .............................................................................. 75 Figure 2.4 Histogram of seeds found per dispersal event ..................................................... 76 Figure 2.5 Probabilities of seed dispersal events occurring in each habitat type ................... 77 Figure 2.6 Histogram of days elapsed ................................................................................. 78 Figure 2.7 Map of successful seed dispersal events ............................................................. 79 Figure 2.8 Histogram of seeds germinated per dispersal event ............................................. 80 Figure 2.9 Boxplots of the percentage of canopy cover by habitat ....................................... 81 Figure 2.10 Boxplots of distance of dispersal event to nearest adult conspecific by habitat. 82 Figure 2.11 Plot of correlation between substrate types and habitats .................................... 83 Figure 2.12 Predicted probability of germination and establishment by habitat.................... 84 Figure 2.13 Predicted probability of germination by day number ........................................ 85 Figure 2.14 Saba seed parasitized by Penicilliopsis calvariiformis ...................................... 86 Figure 2.15 Plot of rainfall recorded at the Fongoli field station .......................................... 87 v LIST OF TABLES Page Table 1.1 Studies of seed dispersal by chimpanzees .............................................................. 8 Table 2.1 Definitions of habitat types found at study site .................................................... 65 Table 2.2 Provenance and quantity of seeds for germination trials....................................... 66 Table 2.3 Germination success of Saba seeds in germination trials ..................................... 67 Table 2.4 Analysis testing