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EL CANIBALISMO SEXUAL EN LA TARÁNTULA IBÉRICA (Lycosa Hispanica): ECOLOGÍA Y EVOLUCIÓN DE ESTRATEGIAS CONDUCTUALES

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EL CANIBALISMO SEXUAL EN LA TARÁNTULA IBÉRICA (Lycosa Hispanica): ECOLOGÍA Y EVOLUCIÓN DE ESTRATEGIAS CONDUCTUALES EL CANIBALISMO SEXUAL EN LA TARÁNTULA IBÉRICA (Lycosa hispanica): ECOLOGÍA Y EVOLUCIÓN DE ESTRATEGIAS CONDUCTUALES TESIS DOCTORAL Rubén Rabaneda Bueno EL CANIBALISMO SEXUAL EN LA TARÁNTULA IBÉRICA (Lycosa hispanica): ECOLOGÍA Y EVOLUCIÓN DE ESTRATEGIAS CONDUCTUALES TESIS DOCTORAL Rubén Rabaneda Bueno Madrid, 2014 Departamento de Ecología Funcional y Evolutiva Estación Experimental de Zonas Áridas CONSEJO SUPERIOR DE INVESTIGACIONES CIENTÍFICAS 1 Rubén Rabaneda Bueno Estación Experimental de Zonas Áridas Consejo Superior de Investigaciones Científicas Carretera de Sacramento, s/n, Cañada de San Urbano E‐04120, Almería, Spain [email protected] Este trabajo ha sido financiado por una beca pre-doctoral I3P-BPD2004-CSIC y el proyecto del Ciencia e Innovación/FEDER (CGL2004-03153) Las fotografías que aparecen a lo largo de esta tesis fueron tomadas por Eva de Mas EL CANIBALISMO SEXUAL EN LA TARÁNTULA IBÉRICA (Lycosa hispanica): ECOLOGÍA Y EVOLUCIÓN DE ESTRATEGIAS CONDUCTUALES Memoria presentada por Rubén Rabaneda Bueno para optar al Grado de Doctor por la Universidad Autónoma de Madrid El Doctorando Rubén Rabaneda Bueno Madrid, septiembre de 2014 3 El Dr. Jordi Moya Laraño, Científico Titular de la Estación Experimental de Zonas Áridas‐CSIC y la Dra. Carmen Fernández Montraveta, Profesora Titular de la Universidad Autónoma de Madrid CERTIFICAN Que los trabajos de investigación realizados en la Memoria de Tesis Doctoral: “El canibalismo sexual en la tarántula ibérica (Lycosa hispanica): Ecología y evolución de estrategias conductuales”, son aptos para ser presentados por el Ldo. Rubén Rabaneda Bueno ante el Tribunal que en su día se designe, para aspirar al Grado de Doctor en Ciencias Biológicas por la Universidad Autónoma de Madrid. Y para que así conste, en cumplimiento de las disposiciones vigentes extendemos el presente certificado a 25 de agosto de 2014 en Almería y Madrid. VºBº Director VºBº Directora Dr. Jordi Moya Laraño Dra. Carmen Fernández Montraveta 5 A mis padres Juan José y María del Carmen, a mis hermanos Juanjo, Raúl y Javier. 7 "El sexo es una trampa de la naturaleza para no extinguirse." — Friedrich Nietzsche 9 Índice Tabla de contenidos ÍNDICE ............................................................................................................................. 1 RESUMEN/ABSTRACT Resumen ........................................................................................................................ 5 Abstract ......................................................................................................................... 8 INTRODUCCIÓN GENERAL Introducción ................................................................................................................ 13 Justificación y Objetivos ............................................................................................ 34 Bibliografía ................................................................................................................. 40 MANSUCRITOS Manuscrito I: Sexual Cannibalism: High Incidence in a Natural Population with Benefits to Females. ........................................................................................ 55 Resumen/Abstract ............................................................................................ 56 Introduction ....................................................................................................... 58 Materials and Methods ...................................................................................... 61 Results ................................................................................................................ 69 Discussion .......................................................................................................... 76 Conclusions ........................................................................................................ 83 Acknowledgments ............................................................................................. 83 References .......................................................................................................... 84 Manuscrito II: Does Female Personality Determine Mate Choice Through Sexual Cannibalism?. ............................................................................................... 89 Resumen/Abstract ............................................................................................ 90 Introduction ....................................................................................................... 92 Materials and Methods ...................................................................................... 94 Results .............................................................................................................. 100 Discussion ........................................................................................................ 102 Conclusions ...................................................................................................... 106 Acknowledgments ........................................................................................... 107 References ........................................................................................................ 108 1 Índice Manuscrito III: Polyandry affects offspring variability in a sexually- cannibalistic species .............................................................................................. 113 Resumen/Abstract .......................................................................................... 114 Introduction ..................................................................................................... 116 Materials and Methods .................................................................................... 119 Results .............................................................................................................. 127 Discussion ........................................................................................................ 130 Acknowledgments ........................................................................................... 133 References ........................................................................................................ 134 Electronic Appendix ........................................................................................ 140 Manuscrito IV: Evolutionary stability of two animal behavioral types: the case of premating sexual cannibalism........................................................ 145 Resumen/Abstract .......................................................................................... 146 Introduction ..................................................................................................... 148 Materials and Methods .................................................................................... 151 Results .............................................................................................................. 158 Discussion ........................................................................................................ 167 Acknowledgments ........................................................................................... 173 References ........................................................................................................ 174 Electronic Appendix ........................................................................................ 181 DISCUSIÓN INTEGRADORA Discusión .................................................................................................................. 195 Bibliografía ............................................................................................................... 211 CONCLUSIONES/CONCLUSIONS Conclusiones ............................................................................................................. 219 Conclusions .............................................................................................................. 221 AGRADECIMIENTOS ...............................................................................................225 2 Índice 3 Resumen 4 Resumen Resumen El canibalismo sexual es un comportamiento extremo en el que las hembras generalmente matan y se alimentan del macho antes, durante o tras el apareamiento, y puede imponer elevados costes reproductores sobre los machos y las hembras. El balance de costes y beneficios dependerá del momento del canibalismo respecto a la cópula, y tendrá la máxima implicación si los individuos que participan en la interacción caníbal aún no se han apareado ya que, si la hembra no encuentra más machos, ninguno de los dos individuos podrá producir descendencia. El canibalismo sexual también puede afectar a la eficacia biológica de las hembras caníbales ya apareadas, cuando la poliandria (la hembra se empareja con más de un macho) contribuye a que la descendencia tenga mayor viabilidad. Sin embargo, si la hembra obtiene un beneficio alimentario y puede conseguir machos adicionales para aparearse, el canibalismo sexual se convierte en un conflicto de intereses extremo, dado que la hembra puede querer canibalizar al macho, mientras que está en el interés de éste último conseguir escapar para copular con otras hembras, Este fuerte conflicto ha hecho que los investigadores se pregunten por el origen evolutivo del canibalismo sexual pre-cópula y su mantenimiento en las poblaciones naturales. Ello ha originado recientemente la interpretación del canibalismo sexual como un síndrome
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