UCLA UCLA Electronic Theses and Dissertations Title Behavioral ecology of cave and epigean Phrynus longipes Permalink https://escholarship.org/uc/item/01w109xj Author Chapin, Kenneth James Publication Date 2016 Peer reviewed|Thesis/dissertation eScholarship.org Powered by the California Digital Library University of California UNIVERSITY OF CALIFORNIA Los Angeles Behavioral ecology of cave and epigean Phrynus longipes A dissertation submitted in partial satisfaction of the requirements for the degree Doctor of Philosophy in Biology by Kenneth James Chapin 2016 © Copyright by Kenneth James Chapin 2016 ABSTRACT OF THE DISSERTATION Behavioral ecology of cave and epigean Phrynus longipes by Kenneth James Chapin Doctor of Philosophy in Biology University of California, Los Angeles, 2016 Professor Peter Nicholas Nonacs, Chair Behavioral researchers using Amblypygi have noted the regularity at which species engage in agonistic interactions. Despite this, why agonistic interactions occur and how they are resolved is unknown. I conducted paired interactions of the amblypygid Phrynus longipes in Puerto Rico to understand the dynamics of agonistic interactions. Through a series of analyses, I found that agonistic interactions are territory contests common across the demographic range of the species. Further, I decoded the strategy that opponents use to negotiate contests, and used resource contests to explain the peculiar pattern of cannibalism that this species exhibits. I used these results to identify the variation in contests and other behavioral phenotypes across cave and surface populations. This research broadens theory of resource contest evolution and behavioral variation by investigating phenomena in a non-model study system. ii The dissertation of Kenneth James Chapin is approved. Gregory F. Grether Eileen Hebets Peter Nicholas Nonacs, Committee Chair University of California, Los Angeles 2016 iii Table of Contents List of Tables ................................................................................................................................. vi List of Figures ............................................................................................................................... vii Acknowledgements ...................................................................................................................... viii Biographical sketch ........................................................................................................................ ix Teaching Experience ....................................................................................................................... x CHAPTER 1: Behavioral ecology of amblypygids ........................................................................ 1 1.1 Abstract .............................................................................................................................. 1 1.2 Forward .............................................................................................................................. 2 1.3 Introduction to the order .................................................................................................... 3 1.3.1 Diversity and evolutionary relationships ................................................................. 3 1.3.2 External morphology ............................................................................................... 4 1.3.3 Sensory physiology and neuroanatomy ................................................................... 5 1.3.4 Reproductive physiology and life history ................................................................ 6 1.4 Environmental interactions ................................................................................................ 7 1.4.1 Microhabitat use and preference ............................................................................. 7 1.4.2 Navigation ............................................................................................................... 9 1.5 Interspecific interactions .................................................................................................. 12 1.5.1 Predators and prey ................................................................................................. 12 1.5.2 Parasites and parasitoids ........................................................................................ 14 1.5.3 Commensalism ...................................................................................................... 15 1.6 Intraspecific interactions .................................................................................................. 16 1.6.1 Contests and territoriality ...................................................................................... 16 1.6.2 Mating systems and mate choice ........................................................................... 18 1.6.3 Parental investment and sociality .......................................................................... 20 1.6.4 Genetics and genomics .......................................................................................... 22 1.7 Conclusion & future directions ........................................................................................ 23 1.8 Acknowledgements .......................................................................................................... 27 CHAPTER 2: Cave-epigean behavioral variation of the whip spider Phrynus longipes (Arachnida: Amblypygi) evidenced by activity, vigilance, and aggression ................................. 55 2.1 Abstract ............................................................................................................................ 55 2.2 Introduction ...................................................................................................................... 56 2.3 Methods ........................................................................................................................... 59 2.3.1 Study site ............................................................................................................... 59 2.3.2 Population density estimate ................................................................................... 60 2.3.3 Behavioural trials ................................................................................................... 61 2.3.4 Statistical analyses ................................................................................................. 62 2.4 Results.............................................................................................................................. 63 2.4.1 Population density ................................................................................................. 63 2.4.2 Behavioral trials ..................................................................................................... 64 2.5 Discussion ........................................................................................................................ 65 2.6 Acknowledgements .......................................................................................................... 67 2.7 Tables & Figures .............................................................................................................. 68 iv CHAPTER 3: Territoriality evidenced by asymmetric intruder-holder motivation in an amblypygid ................................................................................................................................... 77 3.1 Abstract ............................................................................................................................ 77 3.2 Introduction ...................................................................................................................... 78 3.3 Methods ........................................................................................................................... 82 3.3.1 Study animals ........................................................................................................ 82 3.3.2 Behavioral trials ..................................................................................................... 83 3.3.3 Analyses ................................................................................................................ 85 3.4 Results.............................................................................................................................. 85 3.5 Discussion ........................................................................................................................ 87 3.6 Acknowledgements .......................................................................................................... 91 3.7 Appendix A. Supplementary data .................................................................................... 91 3.8 Tables & Figures .............................................................................................................. 92 CHAPTER 4: Cannibalism among rivals: atypical symmetric cannibalism caused by territoriality in the amblypygid Phrynus longipes........................................................................................... 105 4.1 Abstract .......................................................................................................................... 105 4.2 Introduction .................................................................................................................... 106 4.3 Methods ........................................................................................................................