Thesis (doctoral)--Universität, Hamburg, 2008. / Includes bibliographical references.

No description available.

Group-living sets the scene for complex social behaviours such as cooperative breeding, and exploring the factors that shape group-living is crucial in understanding these behaviours. This thesis explores the ecology of a population of the facultative cooperative breeding southern anteater-chat (Myrmecocichla formicivora), a group-living bird species endemic to southern Africa. It reveals a breeding system based around a breeding pair and up to three auxiliary males. Despite equal numbers of males and females produced as fledglings there was a surplus of adult males, which remained philopatric. Dispersal was strongly female biased. Females dispersed within their first year, they dispersed further than males, and they lost the benefits of the natal site. The sex skew in the population suggested that these factors drive differential mortality, with juvenile females having much lower annual survival than juvenile males. Adult survival was higher, with female survival only slightly lower than male survival. Dispersal distances suggested that males selected the breeding location, nearer to their natal site. There was no evidence of surplus non-breeding females. On the loss of a breeding female there was no replacement until new females entered the population, yet if a breeding male disappeared the female promptly re-paired with a male from another group. There was no indication of birds floating in the population, and if males were orphaned or widowed they joined other groups as unrelated helpers in preference to floating. There was no sign of inter-group or individual aggression among chats, and unrelated helpers were peacefully accepted into groups, suggesting mutual benefits. In fact all birds in a group helped raise offspring of the breeding pair, and groups with more helpers fledged more offspring, which implies that both direct and indirect fitness benefits can be gained through joining a group and helping. There was surprisingly little inheritance of breeding position by auxiliaries, and strikingly low levels of extra-pair paternity. This study suggests that the Southern anteater-chat group structure arises through male philopatry due to a shortage of breeding females, the benefits of remaining on the natal site and helping, and the potentially high costs of living alone.

Thesis (Ph. D.)--University of Missouri-Columbia, 1996. / Typescript. Vita. Includes bibliographical references (leaves 461-484). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 1996. / Typescript. Vita. Includes bibliographical references (leaves 461-484). Also available on the Internet.

There is something extraordinary about human culture. The striking complexity of our technologies, institutions, beliefs, and norms has allowed us to colonise the entire planet. One aspect in which human culture is unique relates to its cumulative nature – we accumulate and build on knowledge from the previous generations, leading to incremental improvement in skill, which allows us to produce technologies no one individual could have invented on their own. Understanding the drivers and dynamics of this type of cumulative culture is essential for understanding how human culture has interacted with human evolution. This thesis is concerned with precisely that, and uses a mixture of theoretical and experimental approaches linking individual-level decisions to population-level processes in cumulative culture contexts. Chapter 1 provides some essential background information. In Chapter 2 I used an agent-based simulation model to show that refinement, or incremental improvement in cultural traits, can lead to a drastic decrease of cultural diversity at the population level. This pattern was confirmed using experimental data from a collaborative programming competition in Chapter 3, where I showed that in a cumulative setting, the differential riskiness of copying and innovation drives participants to converge on very similar solutions, leading to a loss of cultural diversity. In Chapter 4 I explored individual differences in social learning strategies, finding considerable variation in how individuals rely on copying, with more successful individuals being more exploratory. I found that successful individuals had more influence on subsequent entries, which is consistent with a prestige bias. Finally, Chapter 5 addressed the link between group structure, diversity, and cumulative improvement. I found that larger groups accumulate more improvement than smaller groups, but smaller groups can also inhibit the convergence patterns we witnessed in larger groups, suggesting an optimal level of connectivity responsible for cumulative improvement.

This thesis re-examines the writing of Raymond Williams. It has two goals. Firstly, it explores Williams's concept of cultural materialism, which theorises the role played by cultural forms in the creation and contestation of a national political order. Secondly, it extrapolates Williams's implicit critique of the unitary British state, and his theory of how cultural forms relate to that state. In Chapter One, I argue that Williams developed his theory of culture by combining a theoretical critique of national literary traditions with an interest in the emergent drama of nineteenth-century Scandinavia and twentieth-century Ireland and Wales. This theme is developed in Chapter Two, where I suggest that certain cultural and political experiences in Wales helped Williams to develop a cultural theory that was more generally applicable. Central to Williams's political aspirations was an attempt to expand and democratise the education system. In Chapter Three, I argue that Williams's novels can be understood as university fiction, providing examples of the kind of university he wished to develop. Since universities arose as institutions generating a sense of unified national culture during the imperial period, to re-think the work of the university is also to re-think the political make-up of the nation. This theme is expanded in Chapter Four, where I argue that Williams related the break-up of the British empire to the break-up of the British state, via devolution in Scotland and Wales. Williams theorised the part played by fiction and other cultural forms in enabling those nations to develop their own voices. He also showed that fiction could provide an imaginative critique of the unitary British state from a series of other perspectives, notably feminism and ethnic subcultures. Finally, in Chapter Five I argue that Raymond Williams can be understood as a film theorist, and demonstrate that a similar renegotiation of British identities occurs in contemporary film. An interest in the political make-up of the British state, and an attempt to develop alternative political and cultural formations, spanned Williams's career. This aspect of his work has hitherto received little critical attention. By discussing Williams in relation to the political break-up of Britain, this thesis makes a significant contribution to our understanding of the Williams oeuvre.

The maintenance of cooperation and altruism in the face of manipulation by exploitative cheaters that reap the benefits of cooperative acts without paying the associated costs is a conundrum in evolutionary biology. Cheaters should spread through a population causing it to crash, yet cooperation is common. There are many models and theories that attempt to explain this apparent contradiction. The social amoeba Dictyostelium discoideum, like many microbial species has been used as a model organism to test these theories and to begin to understand the genetic mechanisms behind social behaviours. The aim of this PhD project is to quantify the interactions that occur between naturally-occurring genotypes during social competition in order to identify the types of cheating behaviours and to understand the evolutionary consequences of such behaviours. I first demonstrate that there is a social hierarchy of genotypes and that cheaters can increase their own fitness by increasing their own spore allocation or decreasing their partner's allocation the precise nature of which is dependent upon unique interactions between each competing pair. I also show that the outcome of social competition is dependent upon the physical environment where it can be significantly reduced, or even avoided by segregation of genotypes during development. Finally, it is demonstrated in a collaborative project that much of the observed social behaviour can be explained in terms of the production of and response to developmental signals.

There is something unique about human culture. Its complex technologies, customs, institutions, symbolisms and norms, which are shared and maintained and improved across countless generations, are what sets it apart from the ‘cultures' of other animals. The fundamental question that researchers are only just beginning to unravel is: How do we account for the gap between their ‘cultures' and ours? The answer lies in a deeper understanding of culture's complex constituent components: from the micro-level psychological mechanisms that guide and facilitate accurate social learning, to the macro-level cultural processes that unfold within large-scale cooperative groups. This thesis attempts to contribute to two broad themes that are of relevance to this question. The first theme involves the evolution of accurate and high-fidelity cultural transmission. In Chapter 2, a meta-analysis conducted across primate social learning studies finds support for the common assumption that imitative and/or emulative learning mechanisms are required for the high-fidelity transmission of complex instrumental cultural goals. Chapter 3, adopting an experimental study with young children, then questions the claim that mechanisms of high-fidelity copying have reached such heights in our own species that they will even lead us to blindly copy irrelevant, and potentially costly, information. The second theme involves investigations of the mutually reinforcing relationship predicted between cultural complexity and ultra-cooperativeness in humans, employing a series of laboratory-based experimental investigations with adults. Chapter 4 finds only limited support for a positive relationship between cooperative behaviour and behavioural imitation, which is believed to facilitate cultural group cohesion. Finally, Chapter 5 presents evidence suggesting that access to cultural information is positively associated with an individual's cooperative reputation, and argues that this dynamic might help to scaffold the evolution of increased cultural complexity and cooperation in a learning environment where cultural information carries high value.

Orientador: Gilda Figueiredo Portugal Gouvea / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Filosofia e Ciencias Humanas / Made available in DSpace on 2018-08-14T05:05:34Z (GMT). No. of bitstreams: 1 Gambarotto_Paola.pdf: 1067569 bytes, checksum: 9343516d695b785d8d5538814c4c0488 (MD5) Previous issue date: 2009 / Resumo: Esta pesquisa tem por finalidade uma análise qualitativa das famílias monoparentais de classe média chefiadas por mulheres na cidade de São Paulo. Por se tratar de um tema amplo, plural e que traz inscrito dimensões como gênero, classe, etnia e trabalho, optamos por circunscrever o foco de observação sobre a transformação da condição feminina na segunda metade do século XX, com especial atenção para o seu processo de individualização. Entende-se que esse processo se dá de diferentes formas, dependendo do grupo social estudado; assim, com base na literatura existente sobre as transformações familiares e a monoparentalidade, observamos, através de entrevistas, a transformação das possibilidades de escolha feminina na classe média. Utilizando conceitos e análises acerca da transformação da vida social e seus desdobramentos para a intimidade, privilegiamos uma reconstrução das mudanças históricas no Brasil, tal como fazem Antony Giddens, Ulrich Beck, Elisabeth Beck-Gernsheim e François de Singly, e construímos um roteiro de entrevistas utilizado com cinco mulheres brancas, de alta escolaridade, naturais do município de São Paulo, divorciadas, com filhos e idades que variam entre 50 e 60 anos. As entrevistas servem como contraponto empírico para uma retomada bibliográfica acerca das transformações das possibilidades biográficas femininas. A faixa etária analisada traz especificidades, pois fez parte do processo de intensificação da entrada feminina no mercado de trabalho, da mobilização feminista da década de 1970 e da legalização do divórcio no Brasil. Trata-se de um grupo que vivenciou mudanças sociais que, mesmo indicando uma maior igualdade feminina na vida pública, não extinguiu totalmente as desigualdades ainda afirmadas pelo mercado de trabalho e pelas representações sociais de gênero / Abstract: The aim of this thesis is the qualitative analysis of middle class one-parent families led by women in São Paulo Capital. As we dealt with a wide-ranging issue, which implies the conceptual dimensions of genre, class, ethnic group and labour, our main concern was to focus on the changes of the female condition in the second half of the 20th century, with special regard to women's individualization process. Varying from group to group, this process occurs in many different ways; thus, keeping in mind authoritative research on family changes and monoparentality, and the reconstruction of Brazilian historical changes as well, we have observed transformations on the possibilities of choice among middle-class women. To grasp these changes, an interview script was developed and applied to five white women, all mothers aged from 50 to 60 years. These interviews serve as empirical counterpart to a bibliographic revision concerning changes on the construction of female biography during the last century. In this sense, the age bracket we focused on brings its specificities, since it corresponds to the intensification of female integration in the market labour, the feminist mobilization of 1970's and, finally, the divorce legalization in Brazil. Even though it is a generation which lived in equal conditions to men in some fields, women of this group still experience inequality affirmed by labour market and genre social representations / Universidade Estadual de Campi / Teoria Sociologica e Pensamento Social / Mestre em Sociologia