Sexual conflict occurs when the fitness interests of males and females do not align with one another. The resolution of sexual conflict often depends on the level of control each sex has on the behavior in conflict. In Pogonomyrmex harvester ants with a genetically determined caste system, two separate lineages interbreed with one another during summer mating swarms. Diploid offspring sired by a single lineage develop into reproductive queens, while offspring sired by opposite-lineage parents develop into sterile workers. This results in sexual conflict, as males which mate with opposite lineage queens will produce only workers, resulting in no fitness benefit, while queens must mate with opposite-lineage males in order to obtain workers and survive. Despite these fitness differences, males do not discriminate between lineages prior to mating. One possible reason for the lack of male discrimination is that queens "mask" their identity cues, making discrimination difficult for males. In eusocial insects, identity cues are encoded by cuticular hydrocarbons (CHC’s) found on the exoskeleton of the insects. These cues contain information on the insect's reproductive status, sex, species, state, and nest membership. In addition to their communication functions, CHC’s also serve as desiccation-resistance molecules, preventing water from freely passing out of the cuticle. However, molecules that are best-suited for communication functions are poor desiccation resistance molecules, and molecules that are best-suited for waterproofing lack the diversity needed for communication; therefore, a tradeoff between these two functions is expected. In this dissertation, I explore sexual conflict in these ants and the chemical recognition cues that likely play a role in this conflict. To test for cryptic strategies in harvester ant mating swarms, I experimentally paired males and females from two interbreeding lineages of harvester ant with different fitness outcomes based on pairing, and measured the propensity to initiate copulation, pre-copulatory time, time in copula, and rate and amount of sperm transferred in each mating. Although females controlled copulation duration, males altered sperm transfer rates, resulting in no quantitative difference in total sperm transfer between lineages. To test for thermal constraints on the diversity and composition of cuticular hydrocarbon profiles, and changes in CHC profiles that occur in workers isolated from the queen, I surveyed the cuticular hydrocarbon profiles of a species complex of harvester ants. The CHC profiles of ants from more xeric environments showed evidence of constraints, while isolated workers differentiated from their queen-raised sisters, although not in queen-specific molecules. To test for queen identity masking and lack of discrimination ability in mating swarms, I tested for convergence in the CHC profiles of reproductives in two hybridizing lineages in response to the sexual conflict playing out in this species. Differences in CHC profiles were lost during the mating swarm, likely limiting male ability to discriminate between mates, limiting discrimination ability in mating swarms. To study the genetic regions that control CHC production, I created a physical linkage map of two of the interbreeding populations, and used that map to perform quantitative trait loci analysis on the cuticular hydrocarbon profile of recombinant males. One significant region associated with 13-methylnonacosane contained numerous odorant receptor genes, suggesting a link between that CHC production and the receptors that detect it, while a second region associated with n-pentacosane contained numerous genes that control expression levels. Overall, the genetic caste determination system in these ants leads to antagonistic coevolution between species. This coevolution is likely reinforced by the thermal constraints and exchange of recognition cues between species, lowering the ability of useful discrimination between lineages during mating swarms.

This thesis deals with the chemical communication of wood mouse of genus Apodemus with a focus on the special sebaceous gland on the ventral side of the tail - the caudal organ. Role of the caudal organ in chemical communication is unclear. To illustrate the function of the sebaceous glands, I decided to use metods of 454 pyrosequencing, proteomic analysis and qPCR. I created a database of transcriptionally active genes of caudal organ using 454 pyrosequencing. In proteomic analysis, I focused on proteins with a molecular weight 14-18kDa to verify the presence of the lipocalins, proteins involved in chemical communication. I compared the relative mRNA abundance of selected genes between individuals of the opposite sex using qPCR. In my research, I found that the caudal organ is active organ and caudal organ could participate in chemical communication. I detected a different relative mRNA abundance of genes in males and females at the mRNA level, which could play a role in differences in development of caudal organ between individuals of the opposite sex. Finally, I suggested possible ways of using the caudal organ in the chemical communication in wood mouse genus Apodemus from the obtained results. Key words: caudal organ, Apodemus, chemical communication, FABP5, Scd1

Au cours d'une histoire évolutive singulière, les systèmes sensoriels des cétacés se sont adaptés à la vie en milieu aquatique. Aujourd’hui, alors que la littérature scientifique regorge de travaux sur leurs capacités acoustiques exceptionnelles, l’utilisation des sens chimiques par ces mammifères marins demeure encore largement méconnue. En effet, malgré quelques rares observations suggérant qu’ils pourraient détecter les composés sécrétés par leurs proies et leurs congénères, les arguments anatomiques et génétiques sont plutôt en faveur d’une régression voire d’une disparition de leurs capacités chémoréceptrices. Les cétacés auraient-ils perdu l’usage de ce canal sensoriel pourtant fondamental pour l’alimentation, la navigation et la reproduction chez les autres grands prédateurs marins ? L’objet principal de ma thèse était donc de déterminer si ces animaux sont capables de percevoir et d’utiliser les indices chimiques présents dans leur environnement en me basant principalement sur une approche comportementale. J’ai ainsi étudié les réactions des cétacés à dents (Odontocètes) et à fanons (Mysticètes) face à différents stimuli solubles ou volatiles, liés directement ou indirectement à leur alimentation. Après avoir mis en évidence, dans des conditions contrôlées, que le grand dauphin discrimine des extraits solubles de ses proies, j’ai développé un protocole permettant de mesurer la réponse des animaux (déplacements et comportements de surface) à des stimuli chimiques, dans leur milieu naturel. Des expériences en Méditerranée occidentale ont révélé que les grands dauphins et les globicéphales (Odontocètes) réagissent au sulfure de diméthyle (DMS), une molécule volatile émise dans les zones de forte productivité primaire. J’ai ensuite mesuré, chez la baleine à bosse (mysticète), la réaction au DMS et à des extraits de proies (krill) dans ses zones de reproduction (Océan Indien) et de nourrissage (Atlantique Nord et Antarctique). Les animaux exposés ont réagi par une augmentation de la fréquence respiratoire et, dans le cas de l’extrait de krill uniquement, par une attraction vers la source du signal (chemotaxis). Nos résultats comportementaux ayant mis en évidence une chémoréception fonctionnelle chez les cétacés, j’ai tenté dans un second temps d’identifier ses bases anatomiques et chimiques. J’ai ainsi initié l’exploration des muqueuses orales et nasales par des techniques d’immunohistochimie, ainsi que l’analyse chimique de leurs sécrétions (urines et fèces) à la recherche de potentielles phéromones. Cette approche innovante et multidisciplinaire a permis de dévoiler l’implication des signaux chimiques dans l’écologie des cétacés. Au-delà de leur aspect fondamental, ces résultats pourraient trouver des applications concrètes pour la gestion et la conservation de ces espèces emblématiques et menacées. / During the course of a unique evolutionary process, the sensory systems of cetaceans (whales, dolphins and porpoises) have secondarily adapted to life in an aquatic environment. While the extraordinary acoustic capacities of these animals have been widely studied, surprisingly little is known about their chemosensory abilities. The results of some sparse behavioural studies suggest that cetaceans can detect molecules secreted by, for example, a prey or congener. In contrast, anatomical and genetic investigations have concluded that cetacean chemosenses are greatly reduced or even absent. This poses the question; have cetaceans truly lost the use of the sensory channels that play a major role in the feeding, orientation and reproduction behaviours of other marine predators? The main objective of this thesis was, therefore, to establish whether these animals are capable of perceiving biologically-relevant chemical cues and exhibiting a behavioural response. For this project, I studied the reactions of both toothed (Odontoceti) and baleen (Mysticeti) whales to various soluble or volatile food-related stimuli. I first worked with captive bottlenose dolphins (Tursiops truncatus) and showed they could discriminate soluble extracts of their piscine prey. I then developed a novel protocol to measure the responses (surface behaviour and movements) of cetaceans to chemical cues in their natural habitat. Using this protocol, experiments performed in the western Mediterranean Sea revealed that both bottlenose dolphins and pilot whales (Globicephala melas) react to dimethyl sulfate (DMS), a volatile molecule found in areas of high primary productivity. Using the same protocol, I subsequently measured the reactions of a mysticete species, the humpback whale (Megaptera novaeangliae) to DMS and to krill extract (their natural prey) in three different locations: in their reproduction zone in the Indian Ocean, and in their feeding grounds in the North Atlantic and Antarctic Ocean. I found that the humpback whales reacted with an increased respiratory rate to both stimuli and that the krill extract also attracted them (chemotaxis). As the results of the behavioural studies suggested the presence of functional chemical senses, I initiated two further studies; (1) a neuroanatomical and immunohistochemical exploration of tissues in the oral and nasal pathways, in order to identify potential chemosensory receptor cells in four species of odontocete, and (2) a chemical analysis of odontocete secretions (urine or feces) in search for potential semiochemicals. Overall, this innovative and multidisciplinary research project revealed that chemical signals are potentially very important in the behavioral ecology of cetaceans. Moreover, these results contribute not only to our fundamental knowledge of the sensory biology of these animals, but they could also have important practical implementations in the conservation of these iconic and threatened species.

A urina é importante na comunicação olfativa de mamíferos, especialmente em roedores: apresenta baixo custo e contém metabólitos potencialmente informativos. Possibilita que o receptor avalie características do emissor (p. ex. espécie, sexo, idade, status de dominância e de saúde, receptividade sexual e o tempo da emissão) a partir da urina encontrada. O balanço hídrico, no entanto, pode ser desvantajoso com o uso da urina na marcação por animais de ambientes xéricos e quentes, já que existe um tradeoff entre o volume de água acessível/ingerido e o emitido na micção/marcação, com pressão seletiva a favor da economia hídrica. Nestes casos pode ocorrer redução na emissão de volume com consequente limitação do uso da marcação por urina. Trinomys yonenagae (Rocha, 1995) (Rodentia, Echimyidae) é altamente afiliativa, endêmica da Caatinga, e pertencente a um gênero de ancestral silvícola, cuja maioria das espécies apresenta fidelidade a ambientes florestados. Produz urina de média osmolaridade e de volume semelhante ao de espécies silvícolas do gênero, embora viva em um paleodeserto de temperatura elevada. Nesse contexto hipotetizamos que T. yonenagae faz uso de marcação por urina, uma estratégia importante para roedores sociais, explorando favoravelmente a restrição filogenética (produção de urina de média osmolaridade) imposta por sua ancestralidade. O padrão de deposição de urina e de fezes de T. yonenagae (n=10) e da espécie-irmã, Trinomys setosus (n=10), de ambiente florestado, foi visualizado sob luz ultravioleta (UV), em sessões individuais (24h), em gaiolas-padrão (40x33x16cm), forradas com papel de filtro. O mesmo procedimento foi usado nas investigações posteriores - a quantificação do número de fezes e das marcas de urinas, com estimativas do volume de marcação (VUt=L total/sessão e L/marca) - em T. yonenagae pré-pubertal (32 a 76d, n=10) e em adultos (um a 11 anos, n=21), de ambos os sexos, em sessões (10min) individuais e em contexto social. Nesse caso os rabos-de-facho adultos foram pareados em compartimentos adjacentes (caixa de 40x30x26cm), com um coespecífico de mesmo sexo, conhecido e desconhecido, e de sexo oposto, desconhecido. Qualitativamente as espécies-irmãs apresentam padrão de disposição de urina semelhantes, provavelmente herdados do ancestral silvícola comum. Há depósitos de dois tipos: marcas grandes, nos cantos da gaiola, e marcas pequenas, distribuídas na área central. Em T. yonenagae, as marcas grandes (VUt=3,00-750,00L, 6,67±4,30% do volume urinário diário), correlacionam-se significativamente (Pearson=0,41; sig.<0,00) com a deposição de fezes, sugerindo deposição de latrina; o VUt das marcas pequenas é de 0,01 a 0,05L. O número de marcas pequenas mais elevado, entre os sujeitos que urinaram, foi de quando pareadas com conhecidas (ANOVA um fator, F=3,70 sig.<0,00), sugerindo coesão social em , e associado a um pequeno investimento hídrico. Observou-se também depósitos de secreções da Glândula Harderiana (GH), que não se correlacionaram com nenhuma das variáveis analisadas. Não ocorreram diferenças estatisticamente significantes nas demais comparações feitas. Em condição solitária, 80% dos indivíduos adultos marcaram (latência <5min), enquanto que o grupo de 26-41d apenas dois sujeitos marcaram. O VUt correlacionouse com a idade positivamente (Pearson=0,64; sig.=0,05), entre os indivíduos jovens, e negativamente entre os adultos (Pearson=-0,39; sig.<0,00), o que sugere que a marcação por urina possa ser hormônio-dependente, como ocorre em outras espécies de roedores. A limitação ao acesso à água no ambiente natural dos rabos-de-facho parece não ter se sobreposto aos fatores de ancestralidade e comunicação social na modulação do comportamento de marcação por urina em T. yonenagae, especialmente para fêmeas que ocupam papel diferenciado na hierarquia social do grupo. O trabalho também salienta a ausência de hierarquia linear nos rabos-de-facho, como anteriormente relatado, e evidencia a presença de atividade da GH, abrindo nova linha de estudos fisiológicos e comportamentais dessa glândula em ratos-de-espinho / Urine is important in olfactive communication in mammals, especially in rodents: its presents low costs and had potentially informatives metabolites. The urine enables the sender to transmit informations about itself (p. ex. species, sex, age, dominance and health status, sexual receptivity, and time of deposit). The water balance, however, can be disadvantageous with the use of urine marking in xeric and hot environments, because there is a trade-off between the amount of water available/ingested and delivered in urination/marking, with pressure selective in favor of the water economy. In these cases there may be a reduction in emission of the volume with consequent limitation of the use of the urine in marking. Trinomys yonenagae (Rocha, 1995) (Rodentia, Echimyidae) is highly affiliative, endemic in the Caatinga, and belongs to a genus of forestry ancestral, which most of species have congruence with forested environments. The rabo-de-facho produces urine with medium osmolarity and volume similar to that of forestry species in the genus, although lives in a high temperature paleodesert. In this context we hypothesized that T. yonenagae marks with urine, an important strategy for social rodents, and explore favorably the phylogenetic constraint (production of medium osmolarity urine) imposed by their ancestral. The pattern of urine and feces deposition of T. yonenagae (n=10) and of the sister-species, Trinomys setosus (n=10), of forested environment, was visualized under ultraviolet light (UV) in individual sessions (24h) in house-cages (40x33x16cm), with the floor covered with filter paper. The same procedure was used in further investigations quantification of the number of feces and of the urine marks, with estimation of the urine volume (VUt = L total/session and L/mark) in pre-puebertal (32 to 76d, n = 10) and adults (one to 11 years, n = 21) T. yonenagae, of both sexes, in 10min sessions under individual and social context. The adults in social context was pared, in an adjacent compartments (of 40x30x26cm box), with a same-sex conspecific, known and unknown, and opposite, sex unknown. Qualitatively, both species shows similar patterns of urine deposition, probably inherited from the forestry ancestral. There are kinds of deposits: larger ones, deposited in the corners of the cage, and small ones, distributed in the central area. In T. yonenagae, the larger marks (VUt = 3,00-750,00L, 6.67 ± 4.30% of the daily urine volume) are significantly correlated (Pearson = 0.41, sig <0.00. ) with the number of feces pellets, suggesting latrine deposition; the VUt of small marks is from 0.01 to 0,05L. The higher number of small marks among subjects who urinated was in paired with known situation (one-way ANOVA, F = 3.70; sig. <0.00), suggesting social cohesion in , and associated with a small water investment. It is also noted deposits of Harderian gland (GH) secretions, which were not correlated with any of the variables. There were no statistically significant differences in the other comparisons. In solitary condition, 80% of adults marked (latency <5min), while only two subjects in the 26-41d group marked. The VUt correlated positively with age (Pearson = 0.64;. sig = 0.05) among young individuals, and negatively among adults (Pearson = -0.39;. sig <0.00). This suggests urine-marking in T. yonenagae as a hormone-dependent behavior, like in other rodent species. The limited access to water in the natural environment of rabo-de-facho seems to have not overlapped the ancestry factors and social communication in the modulation of urine for marking behavior, especially for females occupying distinct role in the social hierarchy the group. The work also highlights the absence of linear hierarchy in rabo-de-facho, as previously reported, and shows the presence of GH activity, opening new line of physiological and behavioral studies of this gland in spiny-rats

Os gatos domésticos podem ser utilizados como modelo no estudo da Família Felidae, pois não atingem grandes proporções físicas, são encontrados em altas densidades populacionais por todo o mundo e compartilham com felinos selvagens grande variedade de marcações odoríferas. A transferência de odores entre os gatos e o meio ambiente ocorre por contatos corporais e eliminação de excretas, sendo urina e fezes importantes carreadores de informação química em quase todos os mamíferos terrestres, facilitando as interações sociais entre os indivíduos. O objetivo do presente estudo foi analisar aspectos do comportamento de gatos domésticos, com destaque para a comunicação química, via fezes e urina, entre estes animais, bem como para as relações entre estes aspectos e sua estrutura social intra-específica. Foram utilizados gatos domésticos (Felis silvestris catus), sem raça definida, de ambos os sexos, incluindo filhotes, juvenis e adultos, sendo estes castrados com um ano de idade, mantidos em alta (0,3 animais/m2) ou em baixa densidade populacional (0,04 animais/m2). A coleta dos dados comportamentais de eliminação de fezes e urina foi realizada utilizando-se o método amostral “animal focal". Foram registrados o número de movimentos e o tempo gasto para cavar um buraco no solo (antes do animal defecar ou urinar), o número de movimentos e o tempo gasto para enterrar as fezes ou urina, e se houve verificação olfativa dos excrementos. Foram registrados os locais onde os animais depositavam suas excretas e foram comparados os comportamentos destes longe ou perto dos locais de descanso e alimentação, na área de alta densidade populacional. Foram, também, comparados os comportamentos dos animais nas duas áreas de estudo. Quanto à organização social, foram registrados quais indivíduos estavam dormindo ou descansando em contato físico direto com outros indivíduos, nas duas áreas. Além disso, foram registrados os locais (caixas) ocupados pelos animais para descanso, em função da altura. Os resultados mostraram que os animais executam número maior de movimentos (com os membros anteriores) e gastam maior tempo para enterrar suas fezes, se comparados à urina. As fêmeas mostram esforço maior do que os machos, após a eliminação das fezes, o que pode indicar uma estratégia para a proteção dos filhotes. Em alta densidade populacional, os animais dedicam maior esforço para enterrar suas fezes, se comparados aos que vivem em baixa densidade. Quanto às verificações olfativas, as fezes são verificadas mais freqüentemente do que a urina, em machos e fêmeas, tanto em alta quanto em baixa densidade populacional. Em alta densidade, tanto os machos quanto as fêmeas depositam suas fezes longe, enquanto depositam sua urina perto dos locais utilizados para descanso e alimentação. Quanto à organização social, a alta densidade populacional parece propiciar maior número de contatos físicos direto entre os animais, do que a baixa densidade. Além disso, os animais preferem ocupar as caixas localizadas em posições mais altas do que as caixas mais baixas, e alguns animais restringem sua ocupação às caixas altas ou baixas, o que pode indicar uma estratificação social, de acordo com a posição hierárquica do animal no grupo. / Domestic cats may be used as a model for the study of the Felidae family, since they do not reach greater physical proportions, are found in high population densities all over the world and share with wild felids a variety of scent marks methods. Odor transference between cats and the environment occurs through corporal contacts and elimination of feces and urine, which seem to be important carriers of chemical information in almost all terrestrial mammals, thus facilitating social interactions between individuals. The aim of the present study was to analyze aspects of the behavior of domestic cats, with emphasis in chemical communication through feces and urine between animals, and the relationships between these aspects and their intraspecific social structure. The study was carried out in domestic cats (Felis silvestris catus) from both sexes, without defined race, including kittens, youthful and adults neutered with nearly one year old; animals were kept in high (0,3 animals/m2) or in low population density (0,04 animals/m2). The collection of the behavioral data for elimination of feces and urine was carried out using the “focal animal" method. The number of movements and the time spent to dig a hole in the ground (before the animals defecate or urinate), the number of movements and the time spent to bury their feces or urine, and whether olfative verification of the excrements was or not performed were carefully recorded. Recordings also involved the places where the animals deposited their excrements and the behavior patterns farther or closer to the places used for rest and feeding were compared, in the area of high population density. Also, the two areas of study were compared regarding animal behavior. As far as social organization is concerned, it was recorded which individuals were sleeping or resting in direct physical contact with other individuals, in both areas of study. Moreover, the places (boxes) used by the animals for resting, in function of their height, were also recorded. Results show that animals execute a greater number of forelimb movements and spend more time to bury feces, when compared to urine. Females show more effort after the elimination of feces than males, which may indicate a strategic behavior for the kitten protection. Animals dedicate more effort to bury feces in high population density, when compared to low population density. Regarding olfative verifications, feces are verified more frequently than urine, for both males and females, not only in high but also in low population density. In high population density, males and females deposit feces farther and urine closer to the places used for rest and feeding. As far as social organization is concerned, high population density seems to propitiate greater number of direct physical contacts between animals than low population density. Moreover, animals show predilection for occupying boxes located in higher positions, than the lower ones, and some animals restrict their occupation to either the high or the low boxes, which may indicate some degree of social stratification in the group, according to animal hierarchical position.

Os gatos domésticos podem ser utilizados como modelo no estudo da Família Felidae, pois não atingem grandes proporções físicas, são encontrados em altas densidades populacionais por todo o mundo e compartilham com felinos selvagens grande variedade de marcações odoríferas. A transferência de odores entre os gatos e o meio ambiente ocorre por contatos corporais e eliminação de excretas, sendo urina e fezes importantes carreadores de informação química em quase todos os mamíferos terrestres, facilitando as interações sociais entre os indivíduos. O objetivo do presente estudo foi analisar aspectos do comportamento de gatos domésticos, com destaque para a comunicação química, via fezes e urina, entre estes animais, bem como para as relações entre estes aspectos e sua estrutura social intra-específica. Foram utilizados gatos domésticos (Felis silvestris catus), sem raça definida, de ambos os sexos, incluindo filhotes, juvenis e adultos, sendo estes castrados com um ano de idade, mantidos em alta (0,3 animais/m2) ou em baixa densidade populacional (0,04 animais/m2). A coleta dos dados comportamentais de eliminação de fezes e urina foi realizada utilizando-se o método amostral “animal focal”. Foram registrados o número de movimentos e o tempo gasto para cavar um buraco no solo (antes do animal defecar ou urinar), o número de movimentos e o tempo gasto para enterrar as fezes ou urina, e se houve verificação olfativa dos excrementos. Foram registrados os locais onde os animais depositavam suas excretas e foram comparados os comportamentos destes longe ou perto dos locais de descanso e alimentação, na área de alta densidade populacional. Foram, também, comparados os comportamentos dos animais nas duas áreas de estudo. Quanto à organização social, foram registrados quais indivíduos estavam dormindo ou descansando em contato físico direto com outros indivíduos, nas duas áreas. Além disso, foram registrados os locais (caixas) ocupados pelos animais para descanso, em função da altura. Os resultados mostraram que os animais executam número maior de movimentos (com os membros anteriores) e gastam maior tempo para enterrar suas fezes, se comparados à urina. As fêmeas mostram esforço maior do que os machos, após a eliminação das fezes, o que pode indicar uma estratégia para a proteção dos filhotes. Em alta densidade populacional, os animais dedicam maior esforço para enterrar suas fezes, se comparados aos que vivem em baixa densidade. Quanto às verificações olfativas, as fezes são verificadas mais freqüentemente do que a urina, em machos e fêmeas, tanto em alta quanto em baixa densidade populacional. Em alta densidade, tanto os machos quanto as fêmeas depositam suas fezes longe, enquanto depositam sua urina perto dos locais utilizados para descanso e alimentação. Quanto à organização social, a alta densidade populacional parece propiciar maior número de contatos físicos direto entre os animais, do que a baixa densidade. Além disso, os animais preferem ocupar as caixas localizadas em posições mais altas do que as caixas mais baixas, e alguns animais restringem sua ocupação às caixas altas ou baixas, o que pode indicar uma estratificação social, de acordo com a posição hierárquica do animal no grupo. / Domestic cats may be used as a model for the study of the Felidae family, since they do not reach greater physical proportions, are found in high population densities all over the world and share with wild felids a variety of scent marks methods. Odor transference between cats and the environment occurs through corporal contacts and elimination of feces and urine, which seem to be important carriers of chemical information in almost all terrestrial mammals, thus facilitating social interactions between individuals. The aim of the present study was to analyze aspects of the behavior of domestic cats, with emphasis in chemical communication through feces and urine between animals, and the relationships between these aspects and their intraspecific social structure. The study was carried out in domestic cats (Felis silvestris catus) from both sexes, without defined race, including kittens, youthful and adults neutered with nearly one year old; animals were kept in high (0,3 animals/m2) or in low population density (0,04 animals/m2). The collection of the behavioral data for elimination of feces and urine was carried out using the “focal animal" method. The number of movements and the time spent to dig a hole in the ground (before the animals defecate or urinate), the number of movements and the time spent to bury their feces or urine, and whether olfative verification of the excrements was or not performed were carefully recorded. Recordings also involved the places where the animals deposited their excrements and the behavior patterns farther or closer to the places used for rest and feeding were compared, in the area of high population density. Also, the two areas of study were compared regarding animal behavior. As far as social organization is concerned, it was recorded which individuals were sleeping or resting in direct physical contact with other individuals, in both areas of study. Moreover, the places (boxes) used by the animals for resting, in function of their height, were also recorded. Results show that animals execute a greater number of forelimb movements and spend more time to bury feces, when compared to urine. Females show more effort after the elimination of feces than males, which may indicate a strategic behavior for the kitten protection. Animals dedicate more effort to bury feces in high population density, when compared to low population density. Regarding olfative verifications, feces are verified more frequently than urine, for both males and females, not only in high but also in low population density. In high population density, males and females deposit feces farther and urine closer to the places used for rest and feeding. As far as social organization is concerned, high population density seems to propitiate greater number of direct physical contacts between animals than low population density. Moreover, animals show predilection for occupying boxes located in higher positions, than the lower ones, and some animals restrict their occupation to either the high or the low boxes, which may indicate some degree of social stratification in the group, according to animal hierarchical position.

A urina é importante na comunicação olfativa de mamíferos, especialmente em roedores: apresenta baixo custo e contém metabólitos potencialmente informativos. Possibilita que o receptor avalie características do emissor (p. ex. espécie, sexo, idade, status de dominância e de saúde, receptividade sexual e o tempo da emissão) a partir da urina encontrada. O balanço hídrico, no entanto, pode ser desvantajoso com o uso da urina na marcação por animais de ambientes xéricos e quentes, já que existe um tradeoff entre o volume de água acessível/ingerido e o emitido na micção/marcação, com pressão seletiva a favor da economia hídrica. Nestes casos pode ocorrer redução na emissão de volume com consequente limitação do uso da marcação por urina. Trinomys yonenagae (Rocha, 1995) (Rodentia, Echimyidae) é altamente afiliativa, endêmica da Caatinga, e pertencente a um gênero de ancestral silvícola, cuja maioria das espécies apresenta fidelidade a ambientes florestados. Produz urina de média osmolaridade e de volume semelhante ao de espécies silvícolas do gênero, embora viva em um paleodeserto de temperatura elevada. Nesse contexto hipotetizamos que T. yonenagae faz uso de marcação por urina, uma estratégia importante para roedores sociais, explorando favoravelmente a restrição filogenética (produção de urina de média osmolaridade) imposta por sua ancestralidade. O padrão de deposição de urina e de fezes de T. yonenagae (n=10) e da espécie-irmã, Trinomys setosus (n=10), de ambiente florestado, foi visualizado sob luz ultravioleta (UV), em sessões individuais (24h), em gaiolas-padrão (40x33x16cm), forradas com papel de filtro. O mesmo procedimento foi usado nas investigações posteriores - a quantificação do número de fezes e das marcas de urinas, com estimativas do volume de marcação (VUt=L total/sessão e L/marca) - em T. yonenagae pré-pubertal (32 a 76d, n=10) e em adultos (um a 11 anos, n=21), de ambos os sexos, em sessões (10min) individuais e em contexto social. Nesse caso os rabos-de-facho adultos foram pareados em compartimentos adjacentes (caixa de 40x30x26cm), com um coespecífico de mesmo sexo, conhecido e desconhecido, e de sexo oposto, desconhecido. Qualitativamente as espécies-irmãs apresentam padrão de disposição de urina semelhantes, provavelmente herdados do ancestral silvícola comum. Há depósitos de dois tipos: marcas grandes, nos cantos da gaiola, e marcas pequenas, distribuídas na área central. Em T. yonenagae, as marcas grandes (VUt=3,00-750,00L, 6,67±4,30% do volume urinário diário), correlacionam-se significativamente (Pearson=0,41; sig.<0,00) com a deposição de fezes, sugerindo deposição de latrina; o VUt das marcas pequenas é de 0,01 a 0,05L. O número de marcas pequenas mais elevado, entre os sujeitos que urinaram, foi de quando pareadas com conhecidas (ANOVA um fator, F=3,70 sig.<0,00), sugerindo coesão social em , e associado a um pequeno investimento hídrico. Observou-se também depósitos de secreções da Glândula Harderiana (GH), que não se correlacionaram com nenhuma das variáveis analisadas. Não ocorreram diferenças estatisticamente significantes nas demais comparações feitas. Em condição solitária, 80% dos indivíduos adultos marcaram (latência <5min), enquanto que o grupo de 26-41d apenas dois sujeitos marcaram. O VUt correlacionouse com a idade positivamente (Pearson=0,64; sig.=0,05), entre os indivíduos jovens, e negativamente entre os adultos (Pearson=-0,39; sig.<0,00), o que sugere que a marcação por urina possa ser hormônio-dependente, como ocorre em outras espécies de roedores. A limitação ao acesso à água no ambiente natural dos rabos-de-facho parece não ter se sobreposto aos fatores de ancestralidade e comunicação social na modulação do comportamento de marcação por urina em T. yonenagae, especialmente para fêmeas que ocupam papel diferenciado na hierarquia social do grupo. O trabalho também salienta a ausência de hierarquia linear nos rabos-de-facho, como anteriormente relatado, e evidencia a presença de atividade da GH, abrindo nova linha de estudos fisiológicos e comportamentais dessa glândula em ratos-de-espinho / Urine is important in olfactive communication in mammals, especially in rodents: its presents low costs and had potentially informatives metabolites. The urine enables the sender to transmit informations about itself (p. ex. species, sex, age, dominance and health status, sexual receptivity, and time of deposit). The water balance, however, can be disadvantageous with the use of urine marking in xeric and hot environments, because there is a trade-off between the amount of water available/ingested and delivered in urination/marking, with pressure selective in favor of the water economy. In these cases there may be a reduction in emission of the volume with consequent limitation of the use of the urine in marking. Trinomys yonenagae (Rocha, 1995) (Rodentia, Echimyidae) is highly affiliative, endemic in the Caatinga, and belongs to a genus of forestry ancestral, which most of species have congruence with forested environments. The rabo-de-facho produces urine with medium osmolarity and volume similar to that of forestry species in the genus, although lives in a high temperature paleodesert. In this context we hypothesized that T. yonenagae marks with urine, an important strategy for social rodents, and explore favorably the phylogenetic constraint (production of medium osmolarity urine) imposed by their ancestral. The pattern of urine and feces deposition of T. yonenagae (n=10) and of the sister-species, Trinomys setosus (n=10), of forested environment, was visualized under ultraviolet light (UV) in individual sessions (24h) in house-cages (40x33x16cm), with the floor covered with filter paper. The same procedure was used in further investigations quantification of the number of feces and of the urine marks, with estimation of the urine volume (VUt = L total/session and L/mark) in pre-puebertal (32 to 76d, n = 10) and adults (one to 11 years, n = 21) T. yonenagae, of both sexes, in 10min sessions under individual and social context. The adults in social context was pared, in an adjacent compartments (of 40x30x26cm box), with a same-sex conspecific, known and unknown, and opposite, sex unknown. Qualitatively, both species shows similar patterns of urine deposition, probably inherited from the forestry ancestral. There are kinds of deposits: larger ones, deposited in the corners of the cage, and small ones, distributed in the central area. In T. yonenagae, the larger marks (VUt = 3,00-750,00L, 6.67 ± 4.30% of the daily urine volume) are significantly correlated (Pearson = 0.41, sig <0.00. ) with the number of feces pellets, suggesting latrine deposition; the VUt of small marks is from 0.01 to 0,05L. The higher number of small marks among subjects who urinated was in paired with known situation (one-way ANOVA, F = 3.70; sig. <0.00), suggesting social cohesion in , and associated with a small water investment. It is also noted deposits of Harderian gland (GH) secretions, which were not correlated with any of the variables. There were no statistically significant differences in the other comparisons. In solitary condition, 80% of adults marked (latency <5min), while only two subjects in the 26-41d group marked. The VUt correlated positively with age (Pearson = 0.64;. sig = 0.05) among young individuals, and negatively among adults (Pearson = -0.39;. sig <0.00). This suggests urine-marking in T. yonenagae as a hormone-dependent behavior, like in other rodent species. The limited access to water in the natural environment of rabo-de-facho seems to have not overlapped the ancestry factors and social communication in the modulation of urine for marking behavior, especially for females occupying distinct role in the social hierarchy the group. The work also highlights the absence of linear hierarchy in rabo-de-facho, as previously reported, and shows the presence of GH activity, opening new line of physiological and behavioral studies of this gland in spiny-rats

Ce travail de thèse vise à mieux comprendre les mécanismes de choix du partenaire chez l'isopode terrestre Armadillidium vulgare. Cette espèce est infectée par la bactérie intracellulaire Wolbachia, connue pour manipuler la sexualité de ses hôtes. Chez Armadillidium vulgare, Wolbachia entraine une féminisation des mâles génétiques, les transformant en femelles fonctionnelles. L'objectif est donc à la fois de comprendre comment les individus choisissent leurs partenaires sexuels, mais également de connaître l'effet de Wolbachia sur ces mécanismes de choix. Afin de répondre à ces questions, une approche comportementale a été utilisée, afin de comparer l'attractivité et le comportement de différents types de femelles. Les résultats montrent que les mâles sont capables de discriminer finement entres des femelles ayant différents traits d'histoire de vie ou différents degrés d'apparentement. Nous montrons également que cette discrimination est corrélée à des changements d'odeur des femelles en fonction de leur état reproducteur et infectieux. Les conséquences de ces choix ont également été étudiées via des expériences de reproduction, et il apparaît que les préférences des mâles sont liées à des bénéfices en termes de succès reproducteur. Quant aux femelles, un suivi sur le long terme de différentes situations de sex-ratio révèle qu'à la fois les mâles et le fait qu'elles soient infectées par Wolbachia diminuent leur fitness, et notamment leur succès reproducteur, allant même jusqu'à modifier leurs préférences sociales. / This work investigates mate choice in the terrestrial isopod Armadillidium vulgare. This species is parasitized with intracellular bacteria Wolbachia, which is known to manipulate the sexuality of its hosts. In Armadillidium vulgare, Wolbachia lead to a feminization of genetic males, transforming them into functional females. The aim of this thesis was both to investigate how individuals choose their mates, and to understand the effect of Wolbachia on such choices. In order to answer these questions, we used a behavioural approach in order to compare the attractiveness and the behaviour of different kinds of females. The results indicate that males are able to accurately discriminate females with different life history traits or different degrees of relatedness. We also show that such discrimination from males toward females is correlated to females odour change, according to both their reproductive and infection status. The consequences of male mate choice were studied through reproduction experiment, and it seems that male’s preferences are linked to benefits in terms of reproductive success. Concerning females, a long-term monitoring in different sex-ratio conditions reveals that both males' presence and Wolbachia infections decrease their fitness, in particular their reproductive success, or even modify their social preferences.

Cuticular hydrocarbons (CHCs) are found on the outer cuticle of all terrestrial arthropods. Although their primary function is in desiccation prevention, these compounds have also been shown to play a variety of roles in insect chemical communication, from species and sex recognition to providing cues of dominance and attractiveness. However, despite growing evidence of their versatility as cues, our knowledge of how CHCs are used in mating interactions is limited to Drosophila and field crickets. In this thesis I investigate the roles CHCs play in interactions at each stage of the mating process in the broad-horned flour beetle Gnatocerus cornutus. I assess the relative importance of CHCs in influencing male reproductive success and examine the complex interplay between different episodes of selection and the mechanisms of sexual selection acting on males. I use a combination of behavioural assays, experimental manipulations and gas chromatography. First, I identify the role of CHCs as cues of sperm competition risk and intensity, demonstrating how the presence of male-derived CHCs on the cuticles of virgin females elicits males to adjust their pre- and post-copulatory investment (chapter 2), by providing information on the state of their competitive environment. I then go on to look at the stability of CHCs as cues of sperm competition over time, finding that they are highly sensitive to environmental degradation (chapter 3) and do not persist in the habitat substrate of this species. Next, I investigate how male CHCs determine fighting and mating success. By estimating and comparing the strength and form of sexual selection imposed by male-male competition and female mate choice, I show that male CHCs are subject to strong antagonistic sexual selection (chapter 4). By experimentally manipulating male CHC profile, I then attempt to verify the selection gradients estimated for female choice 3 (chapter 5). However, my experimental manipulation fails to verify the importance of male CHCs for female mate choice. Finally, I explore the role of same-sex sexual behaviour (SSB) in determining male reproductive success (chapter 6). I find evidence to suggest that SSB may in fact be a form of aggression in its own right, and demonstrate that SSB and fighting may provide equivalent means for males to overcome female choice and secure a mating advantage. My results indicate that CHCs play key roles as chemical cues throughout the mating process and significantly impact male reproductive success. My thesis reveals the intricate nature of the relationships between mechanisms of sexual selection, alongside highlighting the need to consider both the social and physical environment when investigating the importance of chemical cues. I discuss the implications of these results for the evolution of male CHCs and how my findings can be used to further our knowledge of this field.

La génération, propagation et la réception d’informations (bio/chimiques) entre les organismes individuels sont la clé de voûte de nombreux systèmes communicants intelligents et sont omniprésents dans la nature. Les colonies de lucioles synchronisent leurs flashs, et la contraction et l’expansion des muscles cardiaques sont quelques exemples parmi d’autres, où les signaux bio / chimiques générés par des sources synchronisées produisent un comportement coopératif. L’objectif final de cette thèse est de développer une plateforme fiable pour générer des réseaux de communication de liposomes, en encapsulant la réaction de Belousov-Zhabotinsky (BZ) en tant que source d’information ou un signal transmis, et d’étudier la dynamique d’un tel système. Pour atteindre cet objectif, plusieurs questions ont été abordées par une approche “bottom-up” et multi-échelle. Tout d’abord, nous avons étudié l’interaction entre des liposomes de DMPC dopés et non-dopés avec le cholestérol, l’acide myristique, tétradécylsulfate, tétradécylamine, et les espèces impliquées dans la reaction BZ en utilisant la diffusion de rayons X aux petits angles et par spectrophotométrie UV-visible. Des rangées 1D de micro-gouttelettes ont été fabriquées en encapsulant la réaction BZ en microgouttelettes au moyen de la microfluidique et la communication entre les gouttelettes adjacentes a été étudiée. Plus tard, nous avons démontré un système microfluidique facile à monter / démonter avec une conception robuste et une géométrie modulable pour générer des emulsions doubles d’eau dans l’huile dans l’eau (E/ H / O). Enfin, le comportement de ces doubles emulsions générées dans système microfluidique en utilisant des phosphoplipides comme tensioactif et du chloroforme comme phase huileuse, est rapporté. Nous avons montré, avec cette composition de la phase d’huile, que le comportement dynamique des émulsions doubles sous écoulement donne lieu à des phénomènes riches incluant la déformation et du “tip-streaming”. / Generation, propagation and reception of (bio/chemical) information between individual organisms are the keystone of many intelligent communicating systems, and are ubiquitous in Nature. Colonies of fireflies synchronize their flashes, and contraction and expansion of heart muscles are few examples among others, where bio/chemical signals generated by synchronized sources produce a cooperative behaviour. The final objective of this thesis is to develop a reliable platform for generating communicative networks of liposomes, encapsulating the Belousov-Zhabotinsky (BZ) reaction as source of information or transmitted signals, and to study the dynamics of such a system. To reach this goal, several issues were addressed by following bottom-up and multi-scale approaches. First we investigated the interaction between both bulk DMPC liposomes, and liposomes doped with cholesterol, myristic acid, tetradecylsulfate, tetradecylamine, and the species involved in the BZ-reaction by using small angle X-ray scattering (SAXS) and UV-visible spectrophotometry. Than 1D arrays of micro-droplets were fabricated by encapsulating the BZ reaction into microdroplets by means of microfluidics, and the communication between adjacent droplets was studied. Later, we demonstrated an easy to assemble/disassemble and robust design for a microfluidic device with adjustable geometry, for generating monodisperse water-in-oil-in-water (w/o/w) double emulsions. Finally, the behavior of w/o/w double emulsions generated in a microfluidic device, using phospholipids as surfactant and chloroform as the oil phase, was reported. We showed, with this composition of the oil phase, that the dynamic behaviour of the double emulsions under flow gave rise to different phenomena, such as deformation and tip-streaming.