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Post-copulatory sexual selection is a strong evolutionary force, affecting morphological and behavioural traits in males and females in species with polyandrous mating systems. Many insects are subject to sperm competition; sperm from rival males compete to fertilise ova. Since sperm are finite, males should allocate them economically, tailoring ejaculate allocation to suit the reproductive potential of individual matings. Theory suggests when sperm competition risk is high, males should increase sperm numbers to achieve greater reproductive success than their rivals, but evidence of this expected fitness consequence of ejaculate allocation is largely lacking. In this thesis, I use Callosobruchus maculatus beetles to investigate the causes of ejaculate allocation patterns, and to examine whether ejaculate allocation does affect male reproductive success. In Chapter 3, I investigate the effect of rival male presence on ejaculate size and find that, while males grouped with rivals as adults produce bigger ejaculates, their increased effort unexpectedly does not lead to increased reproductive success. In Chapter 4, I examine whether larval conditions also affect ejaculate size, and find that, contrary to sperm competition theory, males reared under dense conditions produce smaller ejaculates than those reared solitarily, and that male reproductive success is consequently elevated in males reared at low larval densities compared to those reared at high densities. In Chapter 5, I then demonstrate that ejaculates produced by low density males contain more sperm than ejaculates produced by high density males, suggesting males do not respond to sperm competition level represented by larval density, but instead suffer resource limitation when reared at high density. In Chapter 6, I investigate the effects of water provision on ejaculate size, and find that males given water produce larger ejaculates, and females given water receive smaller ejaculates. Finally, I link my findings with those of other studies, and suggest my most important result is that plasticity of ejaculate allocation cannot be assumed to be an adaptive behaviour; studies directly measuring the fitness effects of male ejaculate allocation are needed, even when observed patterns conform to theory.

Made available in DSpace on 2014-12-17T14:03:30Z (GMT). No. of bitstreams: 1 RodrigoOA.pdf: 1265658 bytes, checksum: 99f4f1b083a5b39748d0fb4e05fcf79f (MD5) Previous issue date: 2009-02-06 / Chitin is an important structural component of the cellular wall of fungi and exoskeleton of many invertebrate plagues, such as insects and nematodes. In digestory systems of insects it forms a named matrix of peritrophic membrane. One of the most studied interaction models protein-carbohydrate is the model that involves chitin-binding proteins. Among the involved characterized domains already in this interaction if they detach the hevein domain (HD), from of Hevea brasiliensis (Rubber tree), the R&R consensus domain (R&R), found in cuticular proteins of insects, and the motif called in this study as conglicinin motif (CD), found in the cristallography structure of the β-conglicinin bounded with GlcNac. These three chitin-binding domains had been used to determine which of them could be involved in silico in the interaction of Canavalia ensiformis and Vigna unguiculata vicilins with chitin, as well as associate these results with the WD50 of these vicilins for Callosobruchus maculatus larvae. The technique of comparative modeling was used for construction of the model 3D of the vicilin of V. unguiculata, that was not found in the data bases. Using the ClustalW program it was gotten localization of these domains in the vicilins primary structure. The domains R&R and CD had been found with bigger homology in the vicilins primary sequences and had been target of interaction studies. Through program GRAMM models of interaction ( dockings ) of the vicilins with GlcNac had been gotten. The results had shown that, through analysis in silico, HD is not part of the vicilins structures, proving the result gotten with the alignment of the primary sequences; the R&R domain, although not to have structural similarity in the vicilins, probably it has a participation in the activity of interaction of these with GlcNac; whereas the CD domain participates directly in the interaction of the vicilins with GlcNac. These results in silico show that the amino acid number, the types and the amount of binding made for the CD motif with GlcNac seem to be directly associates to the deleterious power that these vicilins show for C. maculatus larvae. This can give an initial step in the briefing of as the vicilins interact with alive chitin in and exert its toxic power for insects that possess peritrophic membrane / A quitina (homopol?mero linear contendo res?duos de β-1,4-N-acetil-D-glicosamina (GlcNac) ? um importante componente estrutural da parede celular de fungos e exoesqueletos de muitos invertebrados pragas, tais como insetos e nemat?ides. Em sistemas digest?rios de insetos forma uma matriz denominada de membrana peritr?fica. Um dos mais estudados modelos de intera??o prote?na-carboidrato ? o modelo que envolve as prote?nas ligantes ? quitina. Dentre os motivos j? caracterizados envolvidos nesta intera??o se destacam o motivo heve?na (HD), obtida de Hevea brasiliensis (Seringueira), o motivo R&R consenso (R&R), encontrado em prote?nas cuticulares de insetos, e o motivo denominado neste estudo como motivo conglicinina (CD), encontrado na estrutura cristalogr?fica da β-conglicinina complexada com GlcNac. Estes tr?s motivos de liga??o ? quitina foram usados para determinar qual(is) deles poderia(m) estar envolvido(s) in silico na intera??o das vicilinas de Canavalia ensiformis e Vigna unguiculata com quitina, como tamb?m associar estes resultados com o WD50 destas vicilinas para larvas de Callosobruchus maculatus. A t?cnica de modelagem comparativa foi utilizada para constru??o do modelo 3D da vicilina de V. unguiculata, que n?o foi encontrada nos bancos de dados. Atrav?s do programa ClustalW obteve-se a localiza??o destes dom?nios na estrutura prim?ria das vicilinas. Os dom?nios R&R e CD foram encontrados com maior homologia nas seq??ncias prim?rias das vicilinas e foram alvos de estudos de intera??o. Atrav?s do programa GRAMM foram obtidos modelos de intera??o ( dockings ) das vicilinas com GlcNac. Os resultados mostraram que, atrav?s de an?lises in silico, o motivo HD n?o faz parte da estrutura das vicilinas, comprovando o resultado obtido com o alinhamento das seq??ncias prim?rias; o motivo R&R, apesar de n?o ter semelhan?a estrutural nas vicilinas, provavelmente tem uma participa??o na atividade de intera??o destas com GlcNac; enquanto que o motivo CD participa diretamente na intera??o das vicilinas com GlcNac. Estes resultados in silico mostram que o n?mero de amino?cidos, os tipos e a quantidade de liga??es feitas pelo motivo CD com GlcNac parecem estar diretamente associados ao poder delet?rio que essas vicilinas possuem para larvas de C. maculatus. Isso pode constutuir um passo inicial na elucida??o de como as vicilinas interagem com quitina in vivo e exercem seu poder t?xico para insetos que possuem membrana peritr?fica

Divergence in the face of gene flow is perhaps the most wildly disputed subject among researchers through time. The debate is an old one and we find its origin as far back as the era of Darwin. The theories dealing with sympatric and parapatric speciation, its processes and ecological conditions, are numerous and the empirical data supporting the ideas is constantly growing. However, the reach of a consensus almost seem as distant as ever. Two fundamental prerequisites can be identified for the evolution of divergence with gene flow, the act of disruptive selection, and the development of assortative mating. A set of models in which speciation with gene flow seem particularly likely is when a shift occurs in host preference in phytophagous insects and mating takes place on the host. In the work behind this thesis, the role of assortative mating in the initial stages of sympatric and parapatric speciation has been studied, as has the interaction between assortative mating and inbreeding and how it effects speciation in small sympatric populations, an aspect not much attended to earlier in the literature. My results show that assortative mating based on resource preference, can evolve rapidly upon secondary contact, and even in parapatric populations with a migration rate of 8% (13-15 individuals) per generation. However for assortative mating to be maintained selection against hybrids is needed. My results also suggests that small inbred populations have a hard time coping with strong assortative mating an as a consequence tend to relax their mating preferences to avoid inbreeding depression. Based on these results, I advocate for the importance of considering not only assortative mating in itself, but also the joint effects of assortative mating and inbreeding when dealing with theories of speciation with gene flow.

Sexual conflict over mating duration drives the evolution of male and female adaptations that facilitate the manipulation of mating interactions in their favor. This conflict drives the evolution of traits that improve the fitness of the focal sex despite inflicting costs on mates. However, males can express multiple traits that increase and decrease female fitness simultaneously. When the effects of male traits on female fitness increase or decrease with duration of exposure, females traits that influence mating duration are selected upon. Females of Callosobruchus maculatus, a bruchid bean beetle, kick mates to forcefully end copulation. Although both negative effects of male genital spines and positive of effects ejaculatory materials on female fitness have been documented, it is not yet clear how these male traits interact to influence the timing of female kicking. In this study, we observed the effect of male genital spine size, ejaculate size and mating history, and manipulated mating duration to disentangle the effects of male traits on the timing of female kicking behavior. We found that male mating history and mate body size dimorphism predicted the timing and duration of female kicking, but that male ejaculate size and spine length did not predict female kicking timing.

Speciation is the process describing the formation of new species and is at the heart of evolutionary biology. According to the biological species concept only reproductively isolated forms are regarded good species. This thesis aims at identifying evolutionary processes that cause population divergence and, ultimately, speciation. Natural and sexual selection are two major candidates driving changes in traits that could render populations reproductively incompatible. In recent years, biologists have recognized that most animal species are polygamous. Therefore, sexual selection does not end at mating but continues to include interactions between individuals after mating has occurred but before zygote formation. Male-male sperm competition and cryptic female choice are two main forms of postmating sexual selection shaping reproductive traits like behaviour. The studies presented in this thesis focus on laboratory experiments attempting to identify the role of postmating sexual selection in causing reproductive divergence across populations in beetles. The majority of studies were performed using a Bruchid beetle, Callosobruchus maculatus, a common, worldwide pest on stored leguminose seeds. I used two major methodological approaches. One approach seeks to identify the traces left by past selection among extant conspecific populations, by assessing the pattern of female reproductive responses to mating with males of decreasing relatedness. Second, I used a selection experiment to disentangle the joint effect of natural and sexual selection acting simultaneously on diverging replicated selection lines. In general, these experiments revealed that postmating sexual selection can be a powerful engine of incipient divergence between allopatric populations. Changes in traits underlying variables such as female reproductive output, female mating rate or male success in sperm competition evolved rapidly and could in some cases effectively reduce gene flow between conspecific populations. While postmating sexual selection per se can drive divergence, I found that interactions with natural selection can limit divergence in reproductive characters. Sexual selection tended to reinforce natural selection under strong directional selection. In contrast, sexual selection inflicted a reproductive load on populations under weak natural selection. Thus, the joint effects of natural and sexual selection on allopatric populations are non-trivial and should be considered in greater detail in future studies of early divergence.

Submitted by Marco Antônio de Ramos Chagas (mchagas@ufv.br) on 2016-07-25T12:33:24Z No. of bitstreams: 1 texto completo.pdf: 655443 bytes, checksum: 60ce546b9212c90a2aea5ec4beba51ec (MD5) / Made available in DSpace on 2016-07-25T12:33:25Z (GMT). No. of bitstreams: 1 texto completo.pdf: 655443 bytes, checksum: 60ce546b9212c90a2aea5ec4beba51ec (MD5) Previous issue date: 2015-12-15 / O feijão-caupi, Vigna unguiculata, (L.), Walp. é uma leguminosa de ampla distribuição mundial, encontrada principalmente nas regiões tropicais. Os grãos de feijão-caupi apresentam problemas sérios de perdas pós-colheita, grande parte ocorrendo em razão do armazenamento inadequado e do ataque por insetos-praga, destacando-se o Callosobruchus maculatus (Coleoptera: Bruchidae). O controle de C. maculatus em feijão-caupi armazenado é feito principalmente com o fumigante fosfina, no entanto, o uso em longo prazo de um único inseticida aumenta o risco do crescimento de populações resistentes. Como alternativa, tem sido pesquisado o uso de inseticidas de origem vegetal que têm relativa toxicidade a diversas espécies de insetos. Este trabalho foi conduzido com o objetivo de avaliar a atividade fumigante do óleo essencial de salsa, Petroselinum sativum, (Mill.) Fuss, sobre C. maculatus, em feijão-caupi. A toxicidade do óleo essencial e do gás fosfina (controle positivo) foi avaliada para estimar as concentrações letais de 50 e 95% (CL 50 e CL 95 ). As unidades experimentais foram constituídas por frascos de vidro com 0,8 L de capacidade, contendo 100 g de feijão-caupi e 20 insetos adultos com idade de 1 a 3 dias. O óleo essencial foi aplicado em recortes de papel colocados dentro de sachês de organza e colados nas tampas dos frascos. A toxicidade foi avaliada 48 h após a exposição dos insetos ao óleo essencial e à fosfina. A taxa instantânea de crescimento populacional dos insetos na presença do óleo essencial e da fosfina foi determinada utilizando as concentrações letais CL 10 , CL 30 , CL 50 , CL 70 e CL 90 obtidas nos bioensaios de toxicidade. O experimento foi montado no delineamento inteiramente casualizado com 5 repetições. A progênie adulta foi contabilizada após 45 dias. Os resultados da toxicidade indicaram CL 50 de 489,5 μL L -1 e CL 95 de 635,8 μL L -1 para o óleo essencial de salsa e CL 50 de 35,7 μL L -1 e CL 95 de 68,5 μL L -1 para a fosfina. Verificou-se que o óleo essencial de salsa apresenta efeito inseticida fumigante no controle de adultos de C. Maculatus e depende da concentração aplicada. Além disso, a perda de massa do feijão-caupi tratado com óleo essencial de salsa e com o gás fosfina foi menor em relação ao controle negativo (sem tratamento), indicando que a exposição dos insetos ao óleo essencial e ao gás fosfina reduziu o número de insetos de C. maculatus. O poder germinativo dos grãos de feijão- caupi foi diretamente proporcional às concentrações do óleo essencial e do gás fosfina. / Cowpea, Vigna unguiculata (L.) Walp. is a legume of worldwide distribution, mainly found in tropical regions. The cowpea grains has serious problems of post-harvest losses, largely occurring due to improper storage and attack by insect pests, highlighting the Callosobruchus maculatus (Coleoptera: Bruchidae). The control of C. maculatus in stored cowpea is done primarily with the phosphine fumigation, however, the long term use of a single insecticide increases the risk of resistant populations development. Alternatively, it has been investigated the use of insecticides of plant origin that have relative toxicity to various insect species. This work was carried out to evaluate the fumigant activity of the essential oil of parsley, Petroselinum sativum (Mill.) Fuss, on C. maculatus in cowpea. Toxicity of essential oil and phosphine gas (positive control) was evaluated to estimate the lethal concentrations of 50 and 95% (LC 50 and LC 95 ). The experimental units consisted of glass bottles with 0.8 liter capacity containing 100 g of cowpea and 20 adult insects aged 1-3 days. The essential oil was applied to paper cutouts placed inside organza sachets and glued to the bottle caps. Toxicity was assessed 48 h after exposure of the insects to the essential oil and phosphine. The instantaneous rate of growth of the insects in presence of the essential oil and phosphine gas was determined using lethal concentration LC 10 , LC 30 , LC 50 , LC 70 and LC 90 obtained in bioassays of toxicity. The experiment was conducted in a completely randomized design with 5 repetitions. The adult progeny was recorded after 45 days. The results of toxicity indicated 489.5 μL -1 to LC 50 and 635.8 μL -1 to LC 95 for essential oil of parsley and 35.7 μL -1 to LC 50 and 68.5 μL -1 to LC 95 for phosphine. It was found that the essential oil of parsley has a fumigant insecticidal effect in controlling adults of C. maculatus which effectiveness depends on the applied concentration. Moreover, the weight loss of the cowpea treated with essential oil of parsley and with phosphine gas was lower compared to the negative control (no treatment), indicating that exposure of the insects to the essential oil and phosphine gas reduced the number of C. maculatus. The germination of cowpea grain was directly proportional to the concentrations of the essential oil and phosphine gas.

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Brazil is one of the largest producers of cowpea [Vigna unguiculata (L.) Walp.], a very important legume for human dietary protein and carbohydrate supply. Nevertheless, there are some factors which limit its productivity and utilization. The insect Callosobuchus maculatus (cowpea weevil) is considered the principal pest that attacks stored grains. In the Northeast of Brazil, breeding efforts involving cowpea have been directed towards the selection of high yielding varieties associated with traits of resistance to diseases and pests. However, studies on the nutritional quality of these improved genotypes are scanty. In this study, the research was conducted with two cowpea genotypes, BR9 Longà e IT81D 1053, susceptible and resistant to cowpea weevil, respectively, to evaluate whether the probable factors related to the resistance would interfere with the nutritional value. Proximate composition showed that both genotypes are good sources of proteins (23.45 and 26.61 g/100 g dry matter), carbohydrates (61.62 and 62.94 g/100 g dry matter) and crude fiber (4.32 and 5.20 g/100 g dry matter), presenting low contents of oil (3.30 and 3.89 g/100 g dry matter). Polyacrylamide gel electrophoresis of the seed flours showed similar patterns for both genotypes, except for the presence of a very prominent 29 kDa band in the resistant genotype. The presence of antinutritional factors such as lectin, urease and trypsin inhibitor was detected in both cowpea genotypes. Lectin (0.10 UH/mgF) and urease (25.13 and 25.41 U/gF) amounts were similar in the susceptible and resistant genotypes. The resistant genotype presented a higher content of trypsin inhibitor (18.55 mg trypsin inhibited/gF) than the susceptible one (12.57 mg trypsin inhibited/gF). Feeding trial conducted with rats fed the experimental diets containing seed flour of BR9 Longà and IT81D 1053 as the sole protein source, at 10% level, were not sufficient to promote animal growth compared to the animals fed the high quality diet containing egg white. However, when compared the treatments containing susceptible and resistant cowpea genotypes most of parameters analyzed were similar. Diets containing the chitin binding proteins (CBP), purified from susceptible and resistant cowpea genotypes and complemented / O Brasil à um dos grandes produtores de feijÃo caupi [Vigna unguiculata (L.) Walp.], uma importante leguminosa para consumo humano por ser boa fonte proteÃnas e carboidratos. Todavia, hà vÃrios fatores que limitam a produtividade e utilizaÃÃo dessa cultura, destacando-se o ataque pelo inseto Callosobruchus maculatus (gorgulho), conhecido como uma das principais pragas de armazenamento. No Nordeste do Brasil, genÃtipos de feijÃo caupi foram criados atravÃs de melhoramento genÃtico, visando aumento da produtividade e resistÃncia a doenÃas e pragas. PorÃm, à detectada a escassez de informaÃÃes relacionando resistÃncia e valor nutricional. Assim sendo, no presente estudo, dois genÃtipos melhorados geneticamente, BR9 Longà e IT81D 1053, suscetÃvel e resistente ao gorgulho, respectivamente, foram selecionados, para verificar se as alteraÃÃes promovidas pelo melhoramento afetariam sua qualidade nutricional. Os dados de composiÃÃo centesimal mostraram que ambos os genÃtipos constituem-se em boa fonte de proteÃnas (23,45 e 26,61 g/100 g de matÃria seca), carboidratos (61,62 e 62,94 g/100 g de matÃria seca) e fibra bruta (4,32 e 5,20 g/100 g de matÃria seca), apresentando baixos conteÃdos de lipÃdios (3,30 e 3,89 g/100 g de matÃria seca). Os perfis eletroforÃticos da farinha de sementes dos dois genÃtipos mostraram-se muito semelhantes entre si, exceto a existÃncia de uma banda mais proeminente na regiÃo de 29 kDa verificada no genÃtipo resistente. Fatores antinutricionais tais como lectina, urease e inibidor de tripsina foram verificados nos dois genÃtipos de feijÃo caupi avaliados. Os teores de lectina (0,10 UH/mgF) e de urease (25,13 e 25,41 U/gF) se mostraram bem similares nos genÃtipos suscetÃvel e resistente. Jà os conteÃdos de inibidor de tripsina foram diferentes, tendo o genÃtipo resistente apresentado maior atividade (18,55 mg de tripsina inibida/gF) em comparaÃÃo ao suscetÃvel (12,57 mg de tripsina inibida/gF). Farinhas dos genÃtipos BR9 Longà e IT81D 1053, quando incluÃdas em dietas para ratos como Ãnica fonte protÃica, a 10%, nÃo foram capazes de promover o crescimento dos animais de forma similar à albumina da clara do ovo (proteÃna padrÃo). Todavia, quando comparado o tratamento AvaliaÃÃo da BiosseguranÃa Alimentar de GenÃtipos... contendo farinha do genÃtipo suscetÃvel com aquele contendo o genÃtipo resistente, para a maioria dos parÃmetros analisados, as respostas foram bem parecidas. Dietas contendo proteÃnas ligantes à quitina (PLQ), purificadas do genÃtipo suscetÃvel e do resistente, complementadas com albumina da clara do ovo, apresentaram valor nutricional igual ou superior ao padrÃo (somente clara do ovo). Diante dos parÃmetros analisados, os resultados permitem concluir que o melhoramento genÃtico do feijÃo caupi, o qual conferiu resistÃncia ao Callosobruchus maculatus, nÃo foi capaz de alterar a qualidade nutricional dessa leguminosa. AlÃm disso, diferentemente ao verificado com o Callosobruchus maculatus, nÃo foram observados efeitos antinutricionais, tÃxicos e/ou alergÃnicos para os animais testados (ratos e camundongos), associados ao consumo das PLQ provenientes do genÃtipo suscetÃvel ou do resistente

In the seed beetle Callosobruchus maculatus, the female is the larger sex and the male is the smaller sex. However, males that are almost as large as females can also occur, which is due to a specific Y chromosome haplotype. This Y chromosome polymorphism is not expected since the Y chromosome does not recombine and has lost genetic variation as a consequence. Nevertheless, the Y chromosome manages to maintain this polymorphism. Thus, the questions asked are how this occurs and how the large male Y haplotype persists to exist since previous studies have shown how small males have the higher fitness. In this study, large males were from line SL3b Y and small males were from line SL1b Y. To answer the questions, two important measures of fitness were conducted, mating- and lifetime reproductive success, as well as lifetime-history traits of the SL1b Y and SL3b Y males. Males from line SL3b Y turned out to have a faster growth rate and a shorter development time compared to the SL1b Y males. Both the SL3b Y males with a shorter development time and the SL1b Y males with a longer development time had larger body sizes. Large males also showed to have heavier ejaculate weight and produced more offspring compared to the other male Y haplotype. However, neither of the males had higher pre-mating success. In conclusion, the two male Y haplotypes must coexist in nature since their traits are beneficial in different environments and circumstances.

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第18826号 / 理博第4084号 / 新制||理||1587(附属図書館) / 31777 / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 曽田 貞滋, 准教授 渡辺 勝敏, 教授 高橋 淑子 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM