Made available in DSpace on 2014-06-11T19:30:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-06-22Bitstream added on 2014-06-13T19:18:46Z : No. of bitstreams: 1 oliveira_vc_me_rcla.pdf: 2151688 bytes, checksum: 544a8f0c3a68d21030ad183c4096e7bb (MD5) / Universidade Estadual Paulista (UNESP) / As vespas, devido à característica difilética do grupo, são um excelente modelo para se tentar compreender a evolução do comportamento social nos Hymenoptera. A biologia e a organização social das vespas eussociais primitivas, em especial o gênero Mischocyttarus, são pouco conhecidas, apesar da grande diversidade de espécies desse gênero nos trópicos. Com o objetivo de identificar os mecanismos envolvidos na regulação social de Mischocyttarus (M.) montei, foram coletadas 9 colônias para a análise da morfofisiologia dos indivíduos, sendo que destas, 6 foram previamente observadas em condições naturais no Campus da Unesp de Rio Claro, SP. Foi verificado que a dinâmica hierárquica desta espécie é regulada através de três estratégias principais: a) interações agonísticas moderadas entre os indivíduos de maneira a permitir que fundadoras se associem, estabelecendo uma hierarquia de dominância mas ao mesmo tempo garantindo a viabilidade da colônia no início do ciclo; b) alimentação e gasto energético diferencial dos adultos, onde os mais dominantes ingerem maiores quantidades de alimento, em especial fontes de proteína, ao mesmo tempo em que realizam tarefas de baixo custo energético e comportamentos relacionados à dominância; e c) utilização da oofagia diferencial como forma indireta de competição e monopolização da postura de ovos. Através desses mecanismos, a hierarquia é regulada de forma dinâmica, de maneira a permitir que 2 qualquer indivíduo possa ocupar diferentes papéis dentro da colônia, uma vez que, como verificado, os adultos emergem com capacidades reprodutivas similares e não apresentam diferenças morfológicas significativas entre as castas. A determinação de suas funções na colônia dependerá, portanto, das estratégias acima descritas. / The wasps, due to their monophyletic characteristics, are an excellent model to explain the evolutionary scenario of the social behavior in the Hymenoptera. The biology and social organization of primitively eusocial wasps, especially of Mischocyttarus genera, are relatively poor studied, despite of its marked diversity in Neotropical regions. With the aim of identify the traits involved in social regulation of M. (Monogynoecus) montei nine colonies were collected and used in morphological and physiological analysis, from these six were monitored in natural conditions at UNESP, in Rio Claro, SP. The results showed that the hierarchical dynamics of this specie is regulated based on three main strategies: a) moderated agonistics interactions among nestmates, which leads to foundress associations foundations and assure the establishment of a dominance hierarchy and the success of the colony in initial phases of development; b) different feeding and energetic cost tasking of adults, whereas the dominant females feed on higher quantities of food, especially protein, and perform tasks with low energetic cost, mainly those related to dominance; and c) differential oophagy as an indirect strategy of competition, avoiding the subordinate oviposition. Through these mechanisms the hierarchy is regulated in a dynamical way, in which any female can assume different tasks in the colony, once the adults emerge with similar reproductive potential and a marked morphological caste differentiation is absent. The role of each nestmate, therefore, will depend on the strategies previously described.

published_or_final_version / Zoology / Doctoral / Doctor of Philosophy

Thesis (Ph.D.)--University of Adelaide, School of Earth and Environmental Sciences, Discipline of Environmental Biology, 2004. / "April 2004" Bibliography: leaves 152-171.

Male fig wasps (Hymenoptera: Chalcidoidea) exhibit a fascinating range of morphology and behaviour. A cluster analysis, based on descriptions of the males of several hundred species, distinguished six major morphological groups. Behaviourial observations suggest that male morphology is related to the levels of inter-male aggression. Three behaviourial groupings were identified. Fighting species generally mated in the fig cavity, pacifist species mated in the females' galls or outside the figs. Mating sites are thus the primary determinants of male morphology and behaviour. In fighting species males were larger than their females, whereas pacifists and aggressors were equal in size or smaller than conspecific females. The large males in fighting fig wasps appear to be a consequence of sexual selection because larger males tended to win fights. Within a species there were no differences in the size of the galls that produced males and females, even in species where sexual size differences were present, suggesting that there is a heritable component to wasp size. No alternative advantages for smaller males were detected. Although fights were sometimes fatal, damage was not always a consequence of fighting behaviour and was recorded in both fighting and pacifist species. Sex ratios in several species were more female biased at higher population densities. Sex ratios of species with 'internally' ovipositing species were heavily female biased, but approached 1:1 in more outbred species with 'externally' ovipositing females. Levels of matedness, among females ranged from 73% to 99%. No evidence for sperm exhaustion was obtained. Species of Philotrypesis with both winged and flightless males were present only in southern African Ficus species from subsections Platyphyllae and Chlamydodorae. No species had only winged males. The flightless males of some Philotrypesis species were themselves polymorphic. In one polymorphic Philotrypesis species, winged males were found to be rare at high densities, but common at low densities. Digitata and religiosa males of Otitesella differed in coloration, size and behaviour. Digitata males were aggressors while religiosa males were fighters. Digitata males escaped from the figs whereas religiosa males remained inside the figs, perhaps because only digitata males were attracted to Light. Proportionally more digitata than religiosa males were present in low density populations and females were found to respond differently to the two morphs.

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Megastigmus spermotrophus is a parasitic chalcid wasp that spends most of its life in the seed of its host, Douglas-fir (Pseudotsuga menziesii). The adult female wasp lays its eggs into the megagametophyte deep within the ovule; the larva prevents an unpollinated ovule from aborting, redirecting resources to feed itself. Host-site selection pressures that influence female oviposition depend on a number of factors. Morphological characteristics of Douglas-fir cones including seed size, seed location, and scale thickness were measured for every ovuliferous scale. Seeds infested by M. spermotrophus as well as seeds fused to galls intiated by a competing conophyte, Contarinia oregonensis were noted. Using a generalized linear mixed effects model, I found that seed position, and the presence of C. oregonensis, were strong predictors of Megastigmus infestation. The percent of M. spermotrophus infested seed was higher in the apical and basal regions of the cone where seeds were smaller, scales were thinner and C. oregonensis were less frequently found. M. spermotrophus was also found to exploit seeds in regions of the cone, where seeds rarely complete development. These data suggest that competitors may not be the only factor influencing infestation; factors of cone morphology are also important. Douglas-fir seed does not show any anatomically detectable defense response to Megastigmus attack. To study mechanisms of host manipulation and defense response of the seed I took a genomics approach. Four types of ovules/seeds were studied: 1. pollinated & uninfested, 2. pollinated & infested, 3. unpollinated & uninfested, and 4. unpollinated and infested. A de novo reference transcriptome was assembled. Transcripts were annotated based on sequence similarity to genes of Pinus taeda, Arabidopsis thaliana, Nasonia vitripennis, and the UniProt database. Expression values were estimated based on the alignment of the original reads back onto the reference transcriptome. Differentially expressed transcripts were identified. Oviposition of M. spermotrophus caused changes in expression of Douglas-fir transcripts. Functional classification of differentially expressed transcripts between infested and uninfested seed revealed genes with possible roles in wounding, but none specific to herbivory. Infested treatments had more transcripts similarly expressed to pollinated than unpollinated seeds suggesting that M. spermotrophus is capable of manipulating gene expression. These transcripts had functional roles related to seed storage, cell division and growth, solute transport, hormone signalling, and programmed cell death among others. Overall, this study reveals a select set of genes that may be involved in stress response to wounding and also genes important for seed development and maturation. / Graduate

Orientador: Márcia Regina Brochetto Braga / Banca: Patricia Ucelli Simioni / Banca: Patricia Pasquali Parise Maltempi / Resumo: A vespa social Polybia paulista é muito agressiva e abundante nos Estados de São Paulo e Sul de Minas Gerais e, responsável por muitos acidentes de importância médica. Os principais alérgenos (Fosfolipase, Hialuronidase e Antígeno 5) de seu veneno já foram caracterizados por estudos proteômicos porém, os estudos em nível molecular estão em andamento pelo nosso grupo. O Antígeno 5 (Ag 5) (~23 kDa) tem sido relatado, em alguns venenos de vespas, como um dos mais abundantes e importantes alérgenos, com elevada prevalência de ligação a IgE (em Vespula vulgaris e em Polistes versicolor) enquanto que em outros, como uma molécula hipoalergênica (em Polybia scutellaris). No Brasil, ainda não existem extratos alergênicos ou componentes padronizados para o tratamento e diagnóstico de alergia ao veneno de Hymenoptera. Neste trabalho, o Ag 5 de P. paulista foi clonado, sequenciado, expresso utilizando a levedura Pichia pastoris X-33, purificado e analisado mediante a imunodetecção por IgE. Os maiores níveis de expressão da proteína recombinante rPoly p 5 foram obtidos em meio BMMY, a 28ºC após 120 horas de indução com metanol. O alérgeno recombinante (rPoly p 5), obtido no meio extracelular, foi purificado por cromatografia de afinidade em resina de Ni+2 e posteriormente por exclusão molecular em coluna de Sephadex-G 100 acoplada a um sistema AKTA-FPLC, com um rendimento de 158 μg/mL. Em paralelo, o Ag 5 nativo (nPoly p 5) foi extraído de glândulas de veneno de P. paulista e purificado a... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The social wasp Polybia paulista is very aggressive and abundant in the states of São Paulo and South of Minas Gerais, responsible for many accidents of medical importance. The major allergens (Phospholipase, Hyaluronidase and Antigen 5) of its venom have already been characterized by proteomic studies. However, studies at the molecular level are in progress by our group. Antigen 5 (Ag 5) (~ 23 kDa) has been reported in some wasp venoms as one of the most abundant and important allergens with a high prevalence of IgE binding (in Vespula vulgaris and in Polistes versicolor), while in others as a hypoallergenic molecule (in Polybia scutellaris). In Brazil, there are no standardized allergenic extracts or components for treatment and diagnosis of allergy to Hymenoptera venoms. In this work, Ag 5 from P. paulista was cloned, sequenced, expressed using the Pichia pastoris X-33 yeast, purified and analyzed by immunodetection by IgE. The highest levels of expression of the rPoly p 5 recombinant protein were obtained in BMMY medium at 28 ° C after 120 hours of methanol induction. The recombinant allergen (rPoly p 5) obtained in the extracellular medium was purified by Ni+2 resin affinity chromatography and subsequently by column exclusion of Sephadex-G 100 coupled to an AKTA-FPLC system with an yield of 158 μg/mL. In parallel, the native Ag 5 (nPoly p 5) from P. paulista venom glands was purified by cation exchange chromatography. Western Blotting analysis was used to evaluate the Ig... (Complete abstract click electronic access below) / Mestre

A fundação por enxameamento e poliginia (múltiplas rainhas funcionais) são características marcantes nas vespas da tribo Epiponini, dominantes na região Neotropical. A diversidade na diferenciação entre castas no grupo é interessante. É evidente a distinção entre rainhas e operárias nos gêneros basais, contrastando com a presença de intermediárias (fêmeas não inseminadas com ovários desenvolvidos) nos gêneros mais derivados. Os objetivos deste trabalho foram conhecer aspectos relacionados ao processo de migração forçada, à organização social inter e intra-castas em Parachartegus fraternus. Certificar-se dos aspectos referentes ao fenômeno da oligoginia cíclica. Os principais resultados foram: O processo de reprodução colonial é um evento de difícil observação. Desse modo, para estudá-lo em detalhes este estudo se valeu da análise de enxameagens provocadas pela remoção das estruturas do ninho de seis colônias naturais de Parachartegus fraternus \"absconding swarms\" (Richards & Richards, 1951). Após essa intervenção observaram-se os seguintes eventos: dispersão majoritária dos adultos, retorno gradativo dos indivíduos aos remanescentes do ninho (área do substrato revestida com material vegetal) e sua permanência no local até o início da migração. Esse evento teve início com muitas vespas deixando o local de agregação anteriormente mencionado, voando ao redor de árvores e arbustos próximos, freqüentemente pousando nas folhas e retornando ao local do ninho original. O comportamento de arrastar o abdômen no substrato \"dragging behavior\" (Naumann, 1975) observado desde a remoção do invólucro e dos favos intensificou-se com o aumento dos referidos vôos. Como esse ato envolve a deposição de substâncias atrativas (Jeanne 1975,1981) sobre vários pontos (principalmente folhas) estabelece-se uma trilha \"trail making\" (Naumann, 1975; Jeanne, 1975, 1981) que atrai outras vespas e, inclusive, novas escoteiras. Essas novas escoteiras, reforçando as marcas anteriores, aumentam a eficiência da trilha que, posteriormente, sendo percorrida pela principal onda migratória guia o enxame propriamente dito até o novo local de nidificação. No caso de P. fraternus, escoteiras foram encontradas em diferentes locais (pré-seleção do local do novo ninho). Entretanto, no local definitivamente selecionado, as escoteiras, repetidamente, além de arrastar o abdômen, depositavam veneno no substrato diferenciando o local de estabelecimento das marcas deixadas no curso da trilha (finalização do caminho químico). Estabelecida a trilha, a migração difusa e massal definitiva ocorre rapidamente. A eficiência do método migratório é notável. Terminada essa fase, no local do ninho antigo restam poucos indivíduos e, principalmente, os machos. Finda a fase migratória operárias retornam várias vezes ao local em que esteve estabelecida a antiga colônia. Essas visitas servem para coletar materiais que serão reutilizados na construção do novo ninho. As rainhas tiveram uma existência pacífica entre elas, no entanto, ficou evidente a competição ligada a postura. A detecção de oofagia diferencial entre as rainhas é importante por ser ela altamente competitiva. A principal função das rainhas é a postura, em colônias estáveis, supostamente, elas inibem a postura de intermediárias. As operárias estão envolvidas no processo de eliminação de rainhas que ocorre de forma gradual ou abrupta. As rainhas supostamente perdem a dominância feromonal ao longo do ciclo colonial e são agredidas por operárias e eliminadas gradualmente da colônia. A eliminação de forma abrupta ocorreu durante o pré¬enxameio e estabelecimento, provavelmente algumas rainhas são feromonalmente reconhecidas como mais fértil e dominante e não são eliminadas. A oligoginia cíclica foi confirmada, restando apenas uma rainha em uma das colônias, e somente depois do desaparecimento de todas rainhas identificadas novas rainhas iniciaram posturas. Em colônia onde foram retiradas rainhas e intermediárias em postura não foi observado novas rainhas em um período de 30 dias, a orfandade refletiu na arquitetura do ninho. As intermediárias foram flexíveis na realização de tarefas ligadas ao forrageio, construção do ninho e enxameio. Porém, a postura de ovos pelas intermediárias pareceu ser facultativa e oportunista dependente da fase e do número de rainhas na colônia, possivelmente, a postura das intermediárias tenha sido suprimida por feromônios de rainhas. As intermediárias foram ativas durante o estabelecimento de algumas colônias, competiram com as rainhas por células para realizar posturas e fizeram oofagia diferencial em ovos de rainhas. No entanto não foi observada nenhuma agressão em intermediárias. Foi observado um caso de substituição da rainha por operária. A fêmea que se tornou rainha foi observada anteriormente em diversas tarefas na colônia ligadas a construção e manutenção. Durante o estabelecimento e a monoginia da colônia, a operária se manifestou como intermediária. No total foi observada por 192 dias desde que foi marcada com código de cores. Assim, em espécies com baixa diferenciação entre as castas, com determinação pós-imaginal, todas as operárias tem possibilidade de se tornar rainha dentro de uma determinada faixa etária. / New nests foundation through swarming and polygyny (multiple functional queens) stand among the most remarkable characteristics of the Epiponini wasps that dominantly thrive in the Neotropics. On morphological grounds inter caste differences range from virtually absent to fair distinctness. Moreover, curious presence of intermediate (uninseminated, ovary-developed females, cf. Richards & Richards, 1951) in most genera add complex characteristics to the Epiponini social organization. For obvious reasons natural swarming in these wasps has been seldom recorded. On this account to gain new insights on the swarming process it was provoked and studied in six colonies of Parachartergus fraternus by removing nests principal structures. On the other hand, need of observing the experimental colonies carefully lead us to approach the wasps social organization through intensive direct observations. In this case, especial attention was paid to the mechanisms leading to cyclical oligogyny, as the mechanisms underlying queen\'s selection, queen\'s competition over egg laying, role of the intermediates, etc., can be adequately approached through direct observations, only. After nest structures removal, majority of the wasps dispersed widely. Their return to the nests remains was invariably gradual, and not organized. So, after using the nest remains as the main aggregation area for a period, migration procedures to o new site started with many wasps departing from the aggregation spot and flying around. Most of these flying wasps used to land on the neighboring vegetation and to return thereafter to the aggregation spot. Abdomen dragging behavior (Naumann, 1975), as observed to occur right after nest\'s structures removal is intensified. Through such peculiar behavior the wasps (scout wasps) add special scents to the dragged spot (Jeanne, 1971, 1975) of which sequential combination (trail making, cf. Naumann, 1975) guides the wasps to the previously chosen new nest site. Efficiency of the scented spots is certainly increased as newcomers scout wasps often perform additional dragging behavior on them. In the course of the observations it could be ascertained that the scout wasps often gather over several spots (nest site pre-selection). Even though abdominal dragging on such spots is intense, it\'s important to stress that only of them received venom deposition through frequent sting acts on the substratum. This may indicate venom deposition signals towards migration end, as odors in it should be different than those left by the dragging behavior. As soon as the scent trail is set definite migration occurs of which efficiency is remarkable as suggested by very low number of wasps left behind on the old nest remain. Among these prevalence of males is notorious. Seemingly they are not able to follow the scent trail as the females do so efficiently. In addition, after the bulk of the population arrives to the new nest site, the scout start returning to the old spot to collect materials to be promptly used in the newly started constructions. In general, queens were quite indifferent one another. However, mild and often non explicit competition trends may take place in the events underlying egg laying. Among such, frequent cases of differential oophagy were recorded what probably points out towards competitive mechanisms. More active queens leave more descendants, supposedly. Queen\'s certainly more evident function relates to oviposition. For such, besides likely competition as afore mentioned it seems also probable that queens can pheromonally inhibit intermediates ovipositions. The mechanism leading to cyclical oligogyny is mediated by the workers. Indeed, groups of workers or even isolated workers respond for the majority of the queen direct attacks. Moreover, mentioned attacks may appear gradually or suddenly. Reasons for such attacks remain unknown. Apparently, in the course of aging the queens may loose their distinctive pheromones what may enhance antagonisms and attacks. Obtained results support cyclical oligogyny. Through it a given colony reached monogyny. In general it was only after queenlessness that the newly produced gynes started ovipositing. In a colony of which queens and intermediates were removed, no queens appeared after 30 days. Orphan colonies develop nests structural abnormalities. Concerning foraging, nest construction and swarming, intermediates were socially flexible. However, their oviposition involvement is seemingly opportunistic as it depends on colony development phase, and number of present queens. It seems likely that intermediates ovipositions can be pheromonally regulated by the queens. In some cases they were more active in the course of colony establishment. Despite, no aggressions were recorded against the intermediates; they were seen eating some of the queens laid eggs. In a given instance a worker substituted a queen. Such worker had been previously recorded in tasks related to nest construction and nest keeping. Besides, as her behavior could be albeit intermittently tracked for 192 days, of which period covered from colony establishment until monogyny through polygyny, it could be ascertained that she invariably performed worker-like functions, that is, she was never seen playing even the role of an intermediate female. However, subsequent dissections performed on the nest population proved that she was the only ovary-developed and inseminated female in that particular colony. This is the most extreme case of caste flexibility ever recorded among the Epiponini wasps. Apparently, incipient caste differences allied to likely occurrence of pos-imaginal caste development in P. fraternus triggered hidden survival mechanisms allowing present especial case of worker-queen substitution event.