Dominance, social organisation and cooperation in the sociable weaver (Philetairus socius)

Simple item page
dc.contributor.advisorRyan, Peter Gen_ZA
dc.contributor.advisorCovas, Ritaen_ZA
dc.contributor.advisorDoutrelant, Claireen_ZA
dc.contributor.advisorvan Dijk, Rene Een_ZA
dc.contributor.authorRat, Margaux Emilie Thereseen_ZA
dc.date.accessioned2016-02-03T14:24:05Z
dc.date.available2016-02-03T14:24:05Z
dc.date.issued2015en_ZA
dc.descriptionIncludes bibliographical referencesen_ZA
dc.description.abstractSociality and cooperation are universal features of life, yet cooperative societies are highly vulnerable to conflicts-of-interests which may lead to societal collapse. Dominance may function as a central mechanism behind the maintenance of cooperative societies, because it may reduce conflict by the establishment of hierarchies, and may act in concert with kin selection, enforcement or signalling mechanisms to promote cooperation. Yet, the significance of dominance in the evolutionary routes that maintain cooperation remains poorly understood (Chapter 1). Sociable weavers Philetairus socius are highly social, cooperative passerines. The species is particularly prone to conflicts because of their year-round coloniality and thus year round sharing of resources. Using extensive field-data on individual behaviour, I examine in this thesis whether dominance may mitigate conflict and maintain cooperation, and how it may inform our understanding of the evolutionary mechanisms underlying cooperation. In Chapter2, I investigate whether hierarchies and phenotypic traits allowing the assessment of social status may have evolved to mediate conflicts. I show that weavers establish ordered hierarchies within colonies and that the size of a melanin-based plumage trait, the black bib, is correlated to social status. In Chapter 3, experimental manipulation supports my proposition of a status signalling function of the bib. In Chapter 4, I investigate the benefits of achieving high social status and whether these are shared with relatives through nepotism. Both dominants and their offspring gain enhanced access to resources. Dominants had more access to breeding positions, although this was not reflected by increased reproductive success. In Chapter 5, I explore how dominance and kinship predict individual cooperativeness to three tasks, nestling provisioning, nest construction and predator mobbing. I find that both explain variation in cooperativeness, yet some results follow opposite directions, revealing multiple routes to cooperation. Finally, in Chapter 6, I examine how dominance and kinship structure weavers' social network and whether network position are linked to cooperativeness. Social network analyses reveal that more central birds are more, related, dominant and cooperative. Chapter 7 concludes that dominance acts in concert with kinship to promote the societal lifestyle of sociable weavers highlighting the potential significance of dominance in the evolution of cooperation.en_ZA
dc.identifier.apacitationRat, M. E. T. (2015). <i>Dominance, social organisation and cooperation in the sociable weaver (Philetairus socius)</i>. (Thesis). University of Cape Town ,Faculty of Science ,Percy FitzPatrick Institute of African Ornithology. Retrieved from http://hdl.handle.net/11427/16714en_ZA
dc.identifier.chicagocitationRat, Margaux Emilie Therese. <i>"Dominance, social organisation and cooperation in the sociable weaver (Philetairus socius)."</i> Thesis., University of Cape Town ,Faculty of Science ,Percy FitzPatrick Institute of African Ornithology, 2015. http://hdl.handle.net/11427/16714en_ZA
dc.identifier.citationRat, M. 2015. Dominance, social organisation and cooperation in the sociable weaver (Philetairus socius). University of Cape Town.en_ZA
dc.identifier.ris TY - Thesis / Dissertation AU - Rat, Margaux Emilie Therese AB - Sociality and cooperation are universal features of life, yet cooperative societies are highly vulnerable to conflicts-of-interests which may lead to societal collapse. Dominance may function as a central mechanism behind the maintenance of cooperative societies, because it may reduce conflict by the establishment of hierarchies, and may act in concert with kin selection, enforcement or signalling mechanisms to promote cooperation. Yet, the significance of dominance in the evolutionary routes that maintain cooperation remains poorly understood (Chapter 1). Sociable weavers Philetairus socius are highly social, cooperative passerines. The species is particularly prone to conflicts because of their year-round coloniality and thus year round sharing of resources. Using extensive field-data on individual behaviour, I examine in this thesis whether dominance may mitigate conflict and maintain cooperation, and how it may inform our understanding of the evolutionary mechanisms underlying cooperation. In Chapter2, I investigate whether hierarchies and phenotypic traits allowing the assessment of social status may have evolved to mediate conflicts. I show that weavers establish ordered hierarchies within colonies and that the size of a melanin-based plumage trait, the black bib, is correlated to social status. In Chapter 3, experimental manipulation supports my proposition of a status signalling function of the bib. In Chapter 4, I investigate the benefits of achieving high social status and whether these are shared with relatives through nepotism. Both dominants and their offspring gain enhanced access to resources. Dominants had more access to breeding positions, although this was not reflected by increased reproductive success. In Chapter 5, I explore how dominance and kinship predict individual cooperativeness to three tasks, nestling provisioning, nest construction and predator mobbing. I find that both explain variation in cooperativeness, yet some results follow opposite directions, revealing multiple routes to cooperation. Finally, in Chapter 6, I examine how dominance and kinship structure weavers' social network and whether network position are linked to cooperativeness. Social network analyses reveal that more central birds are more, related, dominant and cooperative. Chapter 7 concludes that dominance acts in concert with kinship to promote the societal lifestyle of sociable weavers highlighting the potential significance of dominance in the evolution of cooperation. DA - 2015 DB - OpenUCT DP - University of Cape Town LK - https://open.uct.ac.za PB - University of Cape Town PY - 2015 T1 - Dominance, social organisation and cooperation in the sociable weaver (Philetairus socius) TI - Dominance, social organisation and cooperation in the sociable weaver (Philetairus socius) UR - http://hdl.handle.net/11427/16714 ER - en_ZA
dc.identifier.urihttp://hdl.handle.net/11427/16714
dc.identifier.vancouvercitationRat MET. Dominance, social organisation and cooperation in the sociable weaver (Philetairus socius). [Thesis]. University of Cape Town ,Faculty of Science ,Percy FitzPatrick Institute of African Ornithology, 2015 [cited yyyy month dd]. Available from: http://hdl.handle.net/11427/16714en_ZA
dc.language.isoengen_ZA
dc.publisher.departmentPercy FitzPatrick Institute of African Ornithologyen_ZA
dc.publisher.facultyFaculty of Scienceen_ZA
dc.publisher.institutionUniversity of Cape Town
dc.subject.otherOrnithologyen_ZA
dc.titleDominance, social organisation and cooperation in the sociable weaver (Philetairus socius)en_ZA
dc.typeDoctoral Thesis
dc.type.qualificationlevelDoctoral
dc.type.qualificationnamePhDen_ZA
uct.type.filetypeText
uct.type.filetypeImage
uct.type.publicationResearchen_ZA
uct.type.resourceThesisen_ZA
Files
Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
thesis_sci_2015_rat_margaux_emilie_therese.pdf
Size:
4.45 MB
Format:
Adobe Portable Document Format
Description:
Download
Collections
PhD / Doctoral