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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Geschlechterpolitik und Klassenherrschaft : eine Integration marxistischer und feministischer Staatstheorien /

Nowak, Jörg. January 2009 (has links)
Thesis (doctoral)--Universität, Kassel, 2008. / Includes bibliographical references.
62

Från par till föräldrar : om anpassning och skenbar jämställdhet / From couple to parents : about adapting and apparent equality

Ulveseth, Sara, Högberg, Tobias January 2016 (has links)
Sammanfattning Detta är en sociologisk studie som med hjälp av kvalitativa intervjuer har undersökt hur föräldrar upplever övergången från par till föräldrar, samt hur föräldraskapet inverkar på jämställdhet. Att bli förälder är något många i vårt samhälle upplever. Denna övergång är fylld av emotioner, krav och förväntningar. I det svenska samhället har jämställdhet länge varit en högaktuell fråga. Lagar har konstituerats, belöningar har skapats för den som förmått vara jämställd i den bemärkelsen att de delat lika på föräldraledighetsdagarna. Att få barn och skapa en familj är ofta förknippat med kärlek och gemenskap, men sällan synonymt med att känna sig ledig. Snarare är det förknippat med oro, stress, ansvar över såväl barn som att sköta om hemmet. Hemmet kräver omsorg och arbete, men vem som ska utföra arbetet har blivit en fråga att diskutera både i politiken och i familjens vardag. Jämställdhet borde innebära lika ansvar och delaktighet i barnomsorg och hushållsarbete för båda föräldrar. Denna studie visar hur övergången från par till föräldrar ökar känslan av trygghet och gemenskap hos individerna, men också att övergången är liktydig med stress och förväntningar om jämställdhet. Studien visar även att dessa föräldrars syn på jämställdhet är förknippat med arbetsdelning och omsorg främst kring barnet. Då arbetsdelning och jämställdhet kring hushållsarbetet och i parrelationen verkar bortprioriteras, kan fädernas engagemang i barnen skapa en skenbar jämställdhet. I vår studie ser vi en anpassning som är gynnsam för männens relation till sina barn, men ogynnsam för kvinnors rättighet till lika möjligheter och samma värde. / Abstract This is a sociological study using qualitative interviews examining how parents experience the transition from couple to parenthood, and how parenthood affects equality. Becoming a parent is something many in our society experience during their lifetime. This transition is full of emotions, needs and expectations. In Swedish society, gender equality has long been a highly topical issue. Legislation has been constituted, and rewards have been created for those who manage to be equal in the sense that they share equally on parental leave days. To have children and create a family is often associated with love and fellowship, but rarely synonymous with feelings of freedom. Rather, it is associated with anxiety, stress and responsibility over children, as well as taking care of the home. The household requires care and work, but who of the parents that will carry out the work has become an issue to discuss, both in politics and in the family's everyday life. Gender equality should mean equal responsibility and involvement in childcare and household work for both parents. This study shows how the transition from couple to parents increases the sense of a stronger connection between the family members, but also that the transition is synonymous with stress and expectations of equality. This study also shows that the parents' views on gender equality are associated with the division of labor and care primarily concerning the child. As the division of labor and gender equality concerning the household work and in the couple’s relationship lack priority, the father’s involvement in the children create an apparent equality. In our study we see an adaptation favorable to men's relationship with their children, but unfavorable for women's rights to equal opportunities and equal value.
63

TRADE LIBERALIZATION AND DIVISION OF LABOR: IMPLICATIONS FOR POVERTY IN CHINA

Peng, Xuehua 01 January 2006 (has links)
The concomitance of prosperity and poverty come as an enigma in today's world.As some people in this world benefit greatly from advanced technologies andglobalization, others are still suffering heavily from poverty. One noticeable fact is thatalmost all developing countries have their own distinguished "poor area". Such poorareas seem to persist regardless of robust economic growth enjoyed by the overalleconomy.By decomposing the developing country into two regions, one rich coastal regionand one poor inland region, this research establishes a new classical general equilibrium3X2 Ricardian model to investigate how trade liberalization will affect the participationin the division of labor by poor individuals in the inland region in a developing countryand their associated welfare change under different trading conditions.Our model of division of labor on poverty delineates the interdependentrelationship between individuals in the poor inland region, the rich coastal region and thedeveloped country. Market integration plays a very important role in suchinterdependency. Low transaction efficiency is the bottle-neck constraint on the poorinland region's integration into international division of labor through international trade.Thus, it is critical for the poor inland region to improve the market transaction efficiencyin order to enjoy gains from trade.Our marginal and inframarginal analysis show that as an important part of tradeliberalization policy, tariff reduction may not always be a good policy choice for thedeveloping country to alleviate the poverty. Whether tariff reduction makes the inlandregion better off depends on the initial general equilibrium market structure and thedeveloping country's power of influencing its terms of trade. If the developing country islarge enough to determine the terms of trade in international trade with the developedcountry, the developing country may increase the welfare level of the poor inland regionby increasing its tariff rate. But the developed country will oppose it because the tariffrate increase in the developing country will hurt its welfare. Trade negotiation is thennecessary to determine the final tariff rate and the share of gains of trade to each countryand region.
64

Skillnad i arbetstillfredsställelse mellan män och kvinnor inom en könsblandad organisation

Martinsson, My January 2016 (has links)
The aim of this study was to examine if there is a difference in job satisfaction between men and women in a mixed-gender organization. This by comparing men’s and women's job satisfaction based on the work as whole, work tasks and division of labor. Previous research differs in this question, when there is not enough clear relationships that strengthen this and varying results have been demonstrated. Through a crosssectional design, based on a survey, employees in two identical supermarkets were included in the study. Three Mann-Whitney U-tests were then carried out to answer the study questions. The results indicate that there is no significant difference in job satisfaction between men and women. Likewise, there is also no marked differences between men and women in the examined variables, age, length of employment, work environment, motivation and work commitment, which is assumed to be a possible explanation to why gender differences in job satisfaction has not been found. As a result of the low sample in the study the results and conclusions that are presented are not reliable. This study can therefore be seen as a preliminary study for future research that intends to examine gender differences in job satisfaction. / Syftet med denna studie var att undersöka om det föreligger en skillnad i arbetstillfredsställelse mellan män och kvinnor inom en könsblandad organisation. Detta genom att jämföra män och kvinnors arbetstillfredsställelse vad gäller arbetet som helhet, arbetsuppgifter och fördelning av arbetsuppgifter. Tidigare forskning är inte entydiga i denna fråga, då det inte finns tillräckligt klara samband som stärker detta och då varierande resultat har påvisats. Genom en tvärsnittsdesign, baserad på en enkätundersökning, har anställda inom två identiska stormarknader inkluderats i studien. För att besvara studiens frågeställningar har tre Mann-Whitney U-tester utförts. Resultatet från genomförd studie indikerar att det inte föreligger någon signifikant skillnad i arbetstillfredsställelse mellan män och kvinnor. Likaså föreligger det inga markanta skillnader mellan män och kvinnor i de studerande variablerna, ålder, anställningslängd, arbetsmiljö, motivation och engagemang, vilket kan antas vara en rimlig förklaring till varför könsskillnader i arbetstillfredsställelse inte har påträffats. Som en följd av det låga deltagandet i studien är dock inte de resultat och slutsatser som presenteras tillförlitliga. Denna studie kan således ses som en förstudie för framtida forskning som ämnar undersöka könsskillnader i arbetstillfredsställelse.
65

Business Process Outsourcing: An Exploratory Study

Johnson, David 10 August 2005 (has links)
This study examines the emergence of Business Process Outsourcing (BPO) in white collar occupations. Recent BPO practices are compared to the offshore outsourcing of production in the context of the shift from Fordist to flexible production. The study considers BPO in light of Harry Braverman's theory of work degradation and whether or not BPO extends the traditional division of labor between conception and execution to higher skilled white collar occupations. An exploratory qualitative approach comprised of informant interviews, a focus group, and literature review was used to analyze how BPO occurs, why it happens, and where it takes place. I discuss the role of politics and corporate culture in outsourcing white collar jobs and examine the practice of transitioning workers from client to BPO service providers. The study concludes with a skill-based typology of BPO services and suggestions for policy and future research.
66

The Difference in Switching Costs Between Bouts of Identical and Different Tasks in Temnothorax rugatulus

Lausman, Tara Lynne, Lausman, Tara Lynne January 2016 (has links)
A colony of social insects has many tasks to complete for the good of the colony. The tasks, such as brood care, feeding, foraging and building, could be split among its members (implying specialization). Alternatively, ants could just freely switch between tasks, either doing whatever needs to be done or whatever tasks they come into contact with. If individuals switch from one task to another, they may incur costs, including a time cost. So far, research has yet to quantify such task switching costs. To learn more about switching cost, specifically quantifying the cost in terms of time, videos of Temnothorax rugatulus were observed for specific tasks, such as brood care, feeding, foraging and building. The switching costs were measured in two ways depending on whether the non-switching time or switching time were being measured. For the non-switching time between bouts of the same task, the interval time started when the ant stopped touching the brood item and ended when the ant started touching the brood item. For the switching time between two different tasks, time began when the ant stopped one task and ended when the ant began a second task. The interval time was calculated by recording the time, using the timeline on the video, that the ant stopped one task (or bout of one task) and moved on the next. The data collected from the videos were analyzed using a Welch Two-Sample T-test. Through the study, it was discovered that there was, in fact, no significant delay when Temnothorax rugatulus switch from one task to another.
67

Breaking down gender barriers: exploring experiences of underground female mine workers in a mining company

Ledwaba, Sally Kebaabetswe January 2017 (has links)
A research report presented to the Department of Social Work School of Human and Community Development, Faculty of Humanities University of the Witwatersrand, July 2017 / Women have previously been discouraged from pursuing careers in the mining industry given the nature of the work in the field and the physical strength needed to do the work. However, literature has reported an increase in the number of women penetrating the field in recent years (Benya, 2009; Singer, 2002). New legislative frameworks in South Africa, such as the Mining Charter of 2002 (amended 2010) and the Mineral Petroleum Resources Development Act have made provisions for females to be absorbed into the field of mining, but this has not gone without challenges. This study thus sought to gain in-depth understanding of the experiences of underground female mine workers and demystify gender barriers that affect the functioning of women within the mining sector. The study was qualitative in nature and adopted a case study design to richly understand the phenomenon. The study used semi-structured interviews to collect data. Ten participants and two key informants were selected using purposive sampling technique. Data collected from participants was analysed using thematic analysis, in conjunction with the literature reviewed. The study addressed the social and human needs of female mine workers. It was found that, the mining industry has not been progressive in adequately addressing the unique needs of women who work underground. The study was essential in unravelling the experiences of female mine workers and thus made recommendations that can be used to introduce workplace appropriate interventions to be implemented to ensure that underground women mine workers are well accommodated within the industry. / XL2018
68

Women in mining : occupational culture and gendered identities in the making

Benya, Asanda January 2016 (has links)
A thesis submitted to the Faculty of Social Science and Humanities of the University of the Witwatersrand, Johannesburg, South Africa, for the degree of Doctor of Philosophy (Sociology), 2016 / This research contributes to an understanding of how female mineworkers make sense of themselves and how gender identities are constructed in mining. Mine work has for a long time been seen as allowing for particular masculine self-formations and mineworkers embodying specific mining masculine subjectivities. The entrance of women in South African mines from 2004 and their allocation into occupations that were previously exclusively reserved for men is a significant challenge and a disruption to masculine subjectivities and the occupational culture. This thesis illustrates what transpires when socially constructed gender boundaries are crossed. This is what the women are doing with their entry into underground mining. For ten and a half months, between 2011 and 2012 I worked in the mines and lived with mineworkers. During this period I completely submerged myself into the life world of mine workers to get an in-depth understanding of the ways female mineworkers understand themselves and navigate the masculine mining world. I managed to get the subtle, nuanced, instantaneous and unnoticeable ways which produce and reproduce the fluid and contested gender identities. Drawing on insights from a range of feminist theorists and feminist readings of theories I argue that the construction of gendered identities in mining is an ongoing embodied performative process which is articulated in fluid ways in different mining spaces within certain structural, relational and historical constraints. The thesis presents a typology outlining four categories of femininities; mafazi, money makers, real mafazi and madoda straight, that are performed and produced underground by women mineworkers. At home these performances are unstable and disrupted as women attempt to reconcile their role as mothers, wives and their workplace 2 identities as underground miners with their notions of femininity. This necessitates a renegotiation of gender ideologies, performances and identities. In this thesis I succinctly present the fluid, multiple, contradictory and contested processes involved in constructing gendered identities; above ground, underground, and at home. Drawing from this evidence I conclude that women do not approach the workplace or labour process as empty vessels or act as cogs-in the mining machines but are active agents in the construction of their gender identities. The key elements I use to analyse gendered identities are; gendered spaces, embodiment, social and material bodies (as sites of control, resistance and agency) and performativity. I argue that all of these converge and are central to the construction of gendered identities. Key Words: Women in mining, gendered identities, subjectivities, femininities, masculinities, gender performances, embodiment, gendered spaces, gender transformation. / GR2017
69

Race, class and the changing division of labour under apartheid

Crankshaw, Owen January 1994 (has links)
Submitted in fulfilment of the requirements for the degree oi'Doctor of Philosophy, University of the Witwatersrand, Johannesburg / Abstract not clear. / AC 2018
70

"Poliginia e monoginia em Melipona bicolor (Apidae, Meliponini): do coletivo para o individual" / "Polygyny and Mongyny in Melipona bicolor (Apidae, Meliponini):from colective to individual"

Aponte, Olga Ines Cepeda 25 November 2003 (has links)
Cap. 2 Com a finalidade de detectar possíveis diferenças na eficiência do processo de aprovisionamento e postura nas células de cria (POP), comparamos uma colônia monogínica e uma políginica em Melipona bicolor. Ao início das observações na colônia políginica, esta tinha três rainhas das quais uma deixou de ovipositar na metade do período de observações. Por isso separamos em duas partes a base de dados da colônia poligínica de acordo com o número de rainhas poedeiras, três ou duas. Observamos grandes diferenças entre as duas condições das colônias, a monogínica e a poligínica. Nosso estudo permitiu perceber como é a competição entre as rainhas em uma colônia poligínica. Neste tipo de colônia, as rainhas se “precipitavam" por ovipositar e como conseqüência os POPs eram muito mais curtos, diminuindo a postura de ovos tróficos. A rainha da colônia monogínica consumiu mais ovos tróficos e para conseguí-los, aumentava a duração do POP, especificamente a duração do processo de pós-aprovisionamento. O número de operárias em colônias poligínicas que participam do POP, tanto operculadoras quanto aprovisionadoras, também é maior. Isto pode refletir na eficiência do POP em colônias poligínicas: atrai um número maior de operárias que conseguem terminar o processo em menor tempo. Mas também reflete a competição entre as rainhas da colônia poligínica. Nesta, as rainhas estimulavam o POP em células que ainda não estavam com o colar pronto, dificultando seu fechamento pelas operárias. Como resultado da combinação de todos estes fatores, a produção total de ovos é maior na colônia políginica, embora cada rainha individualmente bote menos ovos na colônia poligínica do que a da colônia monogínica. Também detectamos um tipo de dominância, que se refletia no tempo que as rainhas demoravam em colocar seus ovos. Cap. 3 Para entender a poliginia, perguntou-se quais seriam as condições necessárias que levariam a uma associação estável de rainhas. A hipótese sobre “incentivos para permanecer" para as rainhas subordinadas, pode ser relevante para discutir o processo inverso testemunhado em uma colônia poligínica de Melipona bicolor que retornou à condição monogínica. Em nossa colônia poligínica, as três rainhas eram similares em vários aspectos. Não foram encontradas diferenças na competitividade na hora de ovipositar ou consumir ovos tróficos, nem discriminações por parte das operárias. Assim, cada rainha tinha igual oportunidade para pôr ovos ou se alimentar. As rainhas tinham idades semelhantes, e poder-se-ía esperar que o seu desempenho na produção de ovos fosse semelhante. Contudo, elas apresentaram uma clara desigualdade reprodutiva. Também ficou claro que a duração do processo de aprovisionamento e postura (POP) “per se", revelou diferenças como um “marca-passo" das rainhas, especialmente quando estavam sozinhas nas células de cria. A presente investigação descreve possíveis relações entre a taxa de postura das rainhas e fatores nutricionais. Discute-se sobre a provável existência de um feromônio que regularia, nas operárias, o comportamento de fechamento das células. Também se acredita que as operárias possam ter um papel importante no contexto reprodutivo entre múltiplas rainhas. Estes fatores combinados, teriam incrementado as diferenças entre as rainhas, o que levou à interrupção de postura e ao desaparecimento do favo, de duas das rainhas. Cap. 4 Ao acompanhar individualmente as operárias da Melipona bicolor, em colônias monogínica e poligínica, encontramos que existem grandes variações no comportamento de cada uma, sendo que aqueles indivíduos que tinham colocado algum tipo de ovo apareciam como os mais interessados no processo de aprovisionamento e postura (POP). Ao dividir a população de operárias em poedeiras e não poedeiras, constatamos que aquelas que colocaram ovo trófico contribuem efetivamente ao POP, mas que as operárias reprodutivas, apesar de seu pequeno número, conseguem níveis de atividade tão altos que aparentemente excluem as não poedeiras do POP. Também encontramos indivíduos “especiais" por sua extraordinária participação em um ou mais dos comportamentos básicos que compõem o POP, mas estes também parecem movidos principalmente pelo drive de colocar algum tipo de ovo. Entretanto, também encontramos diferenças entre as colônias monogínica e poligínica, mas estas foram difíceis de analisar devido ao momento em que cada colônia começou a ser filmada. Os padrões gerais encontrados tanto para a colônia monogínica, como para a poligínica são muito importantes, pois demonstram que o fato de botar ou não ovos, provoca diferenças quantitativas de comportamento, produzindo desde indivíduos “preguiçosos" até aqueles “hiperativos". Acreditamos que o desenvolvimento ovariano é a causa interna proximal que produz os diversos limiares de resposta individuais. Estes limiares produzem um efeito-cascata, já que a repetição da tarefa é reforçada no próprio indivíduo, e ao mesmo tempo, a atuação deste indivíduo afeta o repertório das outras operárias. A observação das diferenças apresentadas entre operárias poedeiras e não poedeiras, apresenta uma base muito firme para continuar na busca das causas proximais para tal diferenciação. Cap. 5 Os estudos da divisão do trabalho em insetos sociais demonstraram que embora a diferenciação de tarefas baseada na idade seria um fator importante, este mecanismo sozinho imporia uma rigidez nas sociedades que as conduziriam provavelmente à extinção. A plasticidade então é reconhecida como essencial, e a diferenciação entre indivíduos geneticamente similares deve existir. Contudo, a especialização nas tarefas de alguns indivíduos conduz a um melhor desempenho na colônia. Neste capítulo fornecemos evidências de que ocorre especialização no processo de aprovisionamento e postura (POP): poucos indivíduos “especiais" que apresentaram um repertório comportamental específico, e realizam a primeira regurgitação de alimento em Melipona bicolor. Cap. 6 A determinação de castas é um tema amplamente estudado, mas que continua deixando muitas questões a serem solucionadas. Contudo, compreendemos alguns fatos. Reconhece-se a influência de fatores externos como a quantidade e/ou a qualidade do alimento, atuando com hormônios e genes. Já que são as operárias as responsáveis pela administração da quantidade ou da qualidade do alimento, a determinação de castas é socialmente controlada e talvez, entre as aprovisionadoras, existam indivíduos que prefiram criar irmãs rainhas ao invés de irmãs operárias. Para esclarecer esta pergunta, há necessidade de estabelecer a presença ou ausência de secreções glandulares nutritivas no alimento larval, além de técnicas para examinar e acompanhar as operárias aprovisionadoras de alimento larval. Cap. 7 Nos insetos sociais, demonstrou-se que o grau de desenvolvimento dos ovários está correlacionado com relações de dominância, níveis de atividade e com a produção de hormônio juvenil. No epitélio folicular dos ovários, o hormônio juvenil estimula a absorção de nutrientes, mas ao mesmo tempo sabemos que a oogênese é um processo limitado pela disponibilidade de nutrientes. Estas são as causas e efeitos inter-relacionados na reprodução de um indivíduo. Uma das diferenças maiores entre as abelhas do gênero Apis e os meliponíneos, é que as abelhas sem ferrão conseguem desenvolver os ovários e reter a capacidade de botar ovos (embora comumente de natureza trófica) em colônias com rainha. As operárias jovens normalmente desenvolvem seus ovários, principalmente aquelas atendendo ao processo de aprovisionamento e postura (POP). As diversas tarefas relacionadas ao processo são realizadas com diferentes níveis de intensidade por cada indivíduo participando dele. Como demonstramos no capítulo quatro, as operárias que colocam ovos são os indivíduos mais envolvidos no POP contribuindo eficientemente ao processo. Quando em uma colônia monogínica de Melipona bicolor dissecamos as participantes do POP, revelamos que há uma correlação significativa entre a área dos ovários de cada indivíduo com o grau de atividade por ele apresentada. Já que os fatores nutricionais tem um papel importante no desenvolvimento dos ovários, nosso método de correlacionar o peso final com a atividade das abelhas, demonstrou ser adequado para testar indiretamente a influência do alimento na oogênesis. Neste capítulo discutimos o significado evolutivo de manter a capacidade de produzir ovos, em relação com a divisão de trabalho em insetos eussociais. / Cap. 2 In order to detect possible differences in the efficiency of the Provisioning and Oviposition Process (POP), we compared a monogynous from a polygynous colony of Melipona bicolor. At the beginning of observations, the polygynous colony had three laying queens, but one of these ceased to lay when observations where just at the middle. We then decided to split in two the database of the polygynous colony depending on the number of queens laying, being these three or two. ¶ We observed great differences between monogynous and polygynous conditions. In the polygynous colony, our investigation permitted us to perceive the strong competition between queens for laying. In this type of colony, queens were in a “rush" for laying their eggs. As a consequence, POP were very short and this diminished the number of trophic eggs laid. The queen of the monogynous colony consumed many more trophic eggs and in order to achieve this, she would increase the duration of the POP, specifically, the post-provisioning phase. In the polygynous colony, the number of workers, both dischargers and sealers were also greater than in the monogynous colony. This fact could be reflecting a more efficient process in polygynous conditions: more workers are attracted and complete the process in less time. However, again we may perceive the competition between the queens of this colony. The queens stimulated POP in cells that were still not ready, increasing the difficulty for its sealing by the workers. The total outcome of the combination of all these facts is that there is significant major production of queen eggs in the polygynous colony, although the number of eggs laid by each queen is smaller. We also detected a type of dominance reflected on the time queens spent laying their eggs. Cap. 3 There are hypotheses on which could be the necessary conditions that lead to stable multiple queen associations. Some hypothesis state mechanisms such as “staying incentives" for subordinated queens, and may be relevant for discussing the reversal process witnessed in a polygynous colony of Melipona bicolor that shifted to a monogynous condition. In a polygynous colony, three queens were similar in various aspects. Egg laying or consumption of trophic eggs, presented no differences or discriminations and each queen had an equal chance to lay or eat. The queens were of the same age, so it could be expected that they would have a similar performance in egg laying. However, a clear reproductive skew developed. It was also clear that the duration of the provisioning and oviposition process (POP), revealed differences in the pace-marking for the queens principally when alone. ¶ The present paper describes the possible relations between egg laying rate and nutritional factors. We discuss the possible existence of a queen pheromone, regulating the sealing behavior of the workers. Furthermore, workers might play a role in the contest for reproduction among multiple queens. In combination, these factors give rise to increasing differences among the queens resulting in egg laying cessation and disappearance of two of the queens from the comb. Cap. 4 When we followed individual workers of Melipona bicolor in monogynic and polygynic colonies, we found that there are great variations between the behaviors of each bee. Individuals that had laid some type of egg seemed to be the most interested in the provisioning and oviposition process (POP). Therefore, we then analyzed the population dividing them into layers and non layers. We proved that workers that lay trophic eggs contribute effectively to the POP, but reproductive workers, in spite of being so few, achieve such high levels of activity that it seems they exclude the non-laying bees from the process. We also found “special" individuals with an extraordinary participation in one or more of the basic behaviors of the POP, but these also seem to be motivated by the same drive of laying some type of egg. However, we also found differences between the monogynous and polygynous colonies, but these differences were difficult to analyze due to the filming moments for each colony. The general patterns found for both monogynous and polygynous colonies are very important because they demonstrate that the fact of laying an egg provokes quantitative differences in the behaviors, producing from “lazy" individuals up to those “hyperactive". Ovary development is then thought to be the internal proximal cause producing the diverse response thresholds that in a cascade effect, produces an auto-reinforcement when repeatedly performed the task, that at the same time affects the performance of others. The observation on the differences presented by layers and non layers, represents a strudy base to continue exploring the proximal causes for behavioral differentiation. Cap.5 Studies on division of labor have demonstrated that despite being an important factor, etharism alone would impose rigidity to societies and thus, would make them less efficient probably leading them to extinction. Plasticity of behavior is then recognized as essential being expressed as individual differentiation among genetically similar sisters. Furthermore, task specialization of some individuals leads to a better performance of the colony as a whole. In this chapter we give evidence for specialization in the provisioning and oviposition process: a task such as the first discharge of food in Melipona bicolor, is carried out mainly by few, specialized individuals that exhibit a particular behavioral repertory. Cap. 6 Caste determination is a complex topic that has received much attention but remains elusive, leaving many questions to be solved. However, there are some facts that have been comprehended. It is recognized the influence of external factors such as the amount and/or the quality of the food ingested by the larvae, interacting with hormones and genes. Since the workers administrate the larval food, caste determination is socially controlled. Could it happen that among the nurse bees there are individuals that would prefer to raise sister queens than sister workers? To answer this question, it would be necessary to establish the presence or absence of glandular secretions of high nutritional value in the larval food, together with techniques to follow and assess the food dischargers. Through video recordings made on the Provisioning and Oviposition Process (POP) in Melipona bicolor, we recognized two types of food discharges: the first fluid and shiny and another discharge dense and opaque. From each cell filmed we compiled its historical plus the caste in formation. We did not find any relation between the resulting caste and the number of solid or liquid discharges it had received. We discuss why our method may not be an accurate technique to study this difficult and complex topic, but may support future investigations. Cap. 7 Ovary development in social insects has been found to be correlated with dominance relationships, levels of activity and production of juvenile hormone. In the follicular epithelium of ovaries, juvenile hormone stimulates the absorption of nutrients; however, oogenesis is a nutrient limited process. The above roughly summarizes the interrelated causes and effects involved in the reproduction of an individual. One of the biggest differences between Apis bees and stingless bees, is that in queenright conditions, stingless bee workers develop their ovaries retaining their capacity to lay eggs (although most are of a trophic nature). Ovary development is common among young bees attending the provisioning and oviposition process (POP). The several tasks that are involved in the POP are carried on with different levels of intensity by the individuals participating in the process. As we demonstrated in the previous chapter, the individuals that are egg layers are most involved in the POP contributing efficiently to the process. Dissections revealed that there is a significant correlation between the area of the ovaries and the levels of activity presented by the workers of a monogynouos colony of Melipona bicolor. Since nutritional factors also play an important role, our method of correlating the final weight of the bees with activity, proved to be adequate to indirectly test the influence of food in oogenesis. In this chapter we discuss the meaning of retaining the capacity to produce eggs in an evolutionary scenario related to division of labor in eusocial insects.

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