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<p>Alternative reproductive tactics (ARTs) have been described across taxa numerous times, and are especially common in fishes. The advent of molecular techniques has enhanced our understanding of such mating systems, yet these techniques have only been applied to relatively few species. Furthermore, ecological variation has long since been recognized as an important factor influencing mating patterns and sexual selection, yet it is often ignored. In my thesis, I conducted field studies to investigate the reproductive ecology of a species with well characterized ARTs, the plainfin midshipman (<em>Porichthys notatus</em>), and to explore how these mating patterns varied across time and space. This species is characterized by two male tactics: guarders and sneakers. I show that both tactics are successful at gaining fertilization. Indeed, I found evidence for several behavioural adaptations by the guarder male tactic to gain fitness, including guarding, nest takeovers, and plastic cuckoldry behaviours. I also documented the lowest paternity for guarder males for a species with obligate male parental care. Paternity increased over the course of the breeding season, which was likely a result of a higher occurrence of nest takeovers early in the season. In a cross-population analysis of plainfin midshipman, I found significant differences in nest availability and density between two genetically distinct populations, but this did not translate into significant differences in mating patterns. Taken together, my thesis helps elucidate the reproductive ecology of a classic species with ARTs, and has important implications for our understanding of ecological influences on mating patterns and sexual selection.</p> / Doctor of Philosophy (PhD)

Ο Ευρωπαϊκός Θαλασσοκόρακας (Phalacrocorax aristotelis) περιλαμβάνει τρία υποείδη που διαχωρίζονται με βάση μορφολογικές και συμπεριφορικές διαφορές και εξαπλώνονται σε διαφορετικές γεωγραφικές περιοχές. Το ατλαντικό υποείδος, P. a. aristotelis, κατά την αναπαραγωγική του περίοδο, εξαπλώνεται στον Ατλαντικό από τη Β. Ρωσσία μέχρι τις ατλαντικές ακτές της Ιβηρικής χερσονήσου, το υποείδος P. a. riggenbachi διαβιεί στις ακτές της Β. Αφρικής και το μεσογειακό (Phalacrocorax aristotelis desmarestii) θεωρείται ενδημικό υποείδος της Μεσογείου και της Μαύρης Θάλασσας. Η βιολογία και η οικολογία του μεσογειακού θαλασσοκόρακα δεν είναι μελετημένη, ιδιαίτερα στις ανατολικές περιοχές της εξάπλωσής του, παρότι η περιοχή του βόρειου Αιγαίου περιλαμβάνεται στις σημαντικότερες περιοχές αναπαραγωγής του είδους. Η παρούσα διδακτορική διατριβή, αποτελεί την πρώτη μελέτη σχετικά με την οικολογία της αναπαραγωγής και την ανάλυση της γενετικής δομής του μεσογειακού θαλασσοκόρακα σε αποικίες του Αιγαίου. Συγκεκριμένα, μελετώνται τέσσερα θέματα της βιολογίας του υποείδους: (1) η αναπαραγωγική επιτυχία και οι πιθανοί περιβαλλοντικοί παράγοντες που ενδέχεται να την επηρεάζουν, (2) η αναλογία του φύλου των νεοσσών, (3) οι διατροφικές συνήθειες κατά την αναπαραγωγική περίοδο, και (4) η γενετική δομή αναπαραγωγικών πληθυσμών του Αιγαίου, καθώς και οι φυλογεωγραφικές σχέσεις μεταξύ τους και με άλλους μη ελληνικούς πληθυσμούς. / The European Shag (Phalacrocorax aristotelis) is currently divided in three subspecies based on plumage differences, non-overlapping distributions and phenology. The nominate subspecies, P. a. aristotelis, has a breeding distribution from northern Russia to the Atlantic coast of Iberia, P. a. riggenbachi is found along the northern African coasts and the Mediterranean Shag (Phalacrocorax aristotelis desmarestii) is considered an endemic subspecies of the Mediterranean and the Black Seas. The Mediterranean subspecies’ biology and ecology are poorly studied, especially in the eastern part of its distribution, despite the fact that North Aegean Sea (Greece) is considered one of the most important regions for its reproduction. This study presents the first results regarding the study of its reproduction ecology and genetic structure in colonies from the Aegean Sea region. Specifically, four aspects of the its biology are addressed here: (1) breeding success and the possible ecological factors that may affect it, (2) the sex ratio of fledglings, (3) feeding habits during reproduction, and (4) the genetic structure of breeding populations in the Aegean and their phylogeographic relationships with other non-Greek populations.

The evolutionary processes that shape individual variation in continuous behavioural traits remain poorly understood. While the emerging discipline of animal personality is providing increasing evidence that consistent individual differences in behaviour have significant fitness consequences, cognitive traits are yet to be explored in the same manner. My general objective in this thesis was twofold. First, I aimed to examine the ecological significance and fitness consequences of the cognitive trait innovative problem solving-performance, using a population of great tits (Parus major). Second, I aimed to explore the mechanisms underlying the functional significance of ‘exploration behaviour’ a captive measure of the reactive- proactive personality axis, focusing specifically on foraging and risk-taking behaviour. This two-trait approach was expected to shed light on whether personality and cognition simultaneously influence fundamental behaviours. By carrying out behavioural assays on birds temporarily held in captivity, I showed that success at solving a food-motivated problem was repeatable within individuals, consistent between two different tasks and independent of exploration behaviour. Problem-solving performance was positively related to clutch size and fledgling number, established when birds were released back into the wild. Furthermore, when rearing offspring, solvers had shorter working day lengths than non-solvers and foraged over smaller ranges without compromising either provisioning quantity or quality. However, solver females were also more likely to desert their broods than non-solvers and consequently there was little evidence to suggest that directional selection acted on problem-solving performance. In comparison to non-solvers, solver males were also found to be poorer at competing for limited food resources during the winter. Together these findings suggest that costs and benefits are associated with problem-solving performance, which together may act to maintain variation in this trait. My thesis also provides some of the first evidence that exploration behaviour is related to both foraging and risk-taking behaviour in the wild. In comparison to relatively slow explorers, fast exploring males were better competitors at feeders during the winter. Relatively fast and slow explorers also differed in a number of foraging behaviours during offspring provisioning, although not always in the direction predicted from captive work on other populations. Finally, while exploration behaviour was positively correlated with risk- taking behaviour amongst breeding females during incubation, it did not predict nest desertion in response to the risk associated with being trapped by field workers. Collectively these findings suggest that personality measured in captivity has specific but not general power to predict behaviour in the wild. An important facet of evolution is that natural selection is rarely likely to act on a single trait in isolation owing to correlations between traits. This thesis demonstrates how important behaviours in the wild can be simultaneously linked to multiple sources of consistent behavioural variation. It also represents the first large-scale investigation of how variation in a cognitive trait relates to natural behaviour, reproductive life-history variation and fitness in wild animals. Using this individual-based approach in a natural setting may prove to be a useful tool for understanding how selection acts on cognitive traits.

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.

Para avaliar a quantidade ótima de energia e recursos a ser investida em reprodução, um animal deve não só acessar informações sobre sua própria condição corporal, como acessar também informações sobre coespecíficos presentes no ambiente em que vive. Este trabalho investigou essas duas vias (endógena e exógena) de obtenção de informação. Utilizando como organismo modelo a aranha Paratrechalea ornata (Trechaleidae), uma espécie em que os machos produzem presentes nupciais, este estudo investigou: (a) se machos investem mais tempo de busca quando na presença de pistas químicas de fêmeas virgens; (b) se machos aumentam ou diminuem o investimento na produção do presente nupcial quando há pistas da presença de machos competidores; (c) se restrições alimentares impõem efeitos de curto e longo prazo sobre o comportamento de construção de presentes nupciais. Machos mostraram preferência por locais com pistas da presença de fêmeas, mas não diferenciaram pistas de fêmeas virgens e copuladas. Diante de pistas da presença de um macho competidor, machos produziram presentes de menor qualidade, com menos seda. Por fim, restrições alimentares provocam efeitos de curto e longo prazo no comportamento reprodutivo dos machos, diminuindo a frequência de produção do presente nupcial e o tamanho do presente construído. Conjuntamente, os três experimentos realizados mostram que machos de P. ornata utilizam tanto informações exógenas quanto endógenas para ajustar seu investimento em reprodução. A combinação das informações obtidas deve aumentar a eficiência no gasto de energia, maximizando o sucesso reprodutivo dos machos sem que isso prejudique a manutenção de seu organismo / To evaluate the optimal amount of energy and resources to be invested in reproduction, animals should not only obtain information about their own body condition, but they should also obtain information about conspecifics in the environment where they live. This study investigated these two ways (endogenous and exogenous) of acquiring information. Using as model organism the spider Paratrechalea ornata (Trechaleidae), a species in which males produce nuptial gifts, this study investigated: (a) if males invest more time searching for sexual partners in the presence of chemical cues of virgin females; (b) if males increase or decrease the investment in nuptial gift construction in the presence of chemical cues of competitor males; (c) if food deprivation imposes short- and long-term effects on nuptial gift construction. Males showed a preference for sites with cues of females, but they did not discriminate cues of virgin from cues of copulated females. When males detected cues of a male competitor, they produced lower quality gifts, with less silk. Finally, food deprivation imposed both short- and long-term negative effects on male reproductive behavior, decreasing the frequency of nuptial gift construction and also the size of the gift. Together, the three experiments show that males of P. ornata use both exogenous as endogenous information to adjust their investment in reproduction. The combination of information obtained may increase the efficiency in energy use, maximizing male reproductive success without compromising self maintenance

Orientador: Elza Guimarães / Resumo: Nessa tese estudamos duas espécies melitófilas de Bignoniaceae, Jacaranda caroba e J. decurrens, que coocorrem em formações savânicas de cerrado e que se mostraram modelos interessantes para explorarmos aspectos ecológicos e evolutivos relacionados à sua reprodução sexual, tendo em vista que apresentam uma complexa rede de interações com mutualistas e antagonistas. A sobreposição geográfica dessas duas espécies nos permitiu avaliar padrões de coexistência relacionados à dinâmica de florescimento, bem como seu anúncio floral relacionado à atração de visitantes florais mutualistas e antagonistas. Além disso, essa interação com mutualistas e antagonistas possibilitou averiguar o impacto da atuação de antagonistas que roubam néctar sobre a polinização de ambas as espécies e como os danos realizados por abelhas roubadoras de néctar interferem na sinalização visual e química aos polinizadores. Também avaliamos a exploração de néctar por diferentes grupos funcionais de visitantes florais de J. caroba e J. decurrens. Por fim, considerando que o sucesso reprodutivo está diretamente relacionado com a eficiência da polinização investigamos o sistema reprodutivo dessas duas espécies e o efeito da qualidade do pólen transferido entre flores associado ao comportamento dos polinizadores durante o forrageamento, buscando compreender os fatores intrínsecos relacionados à seleção mecanismos de autoincompatibilidade nas populações naturais amostradas. / Abstract: In this dissertation we studied two mellithiphilous Bignoniaceae species, Jacaranda caroba and J. decurrens, that co-occur in savanic cerrado formations. This is an interesting model to explore ecological and evolutionary aspects related to their sexual reproduction taking into account that they present a complex network of interactions with mutualists and antagonists. These species‟ geographical overlap allowed us to evaluate patterns of coexistence related to the flowering dynamics, as well as its floral display related to the attraction of mutualists and antagonists‟ floral visitors. Besides, their interactions with mutualists and antagonists allowed us to evaluate the impact of nectar-robbing antagonists on both species and how damage by nectar-robber bees interferes with visual and chemical signaling to pollinators. We also evaluated the nectar exploitation by different functional groups of J. caroba and J. decurrens floral visitors. Finally, considering that these species‟ reproductive success and the effect of pollinator behavior during foraging on the quality of the pollen that is transferred among flowers. Considering that species‟ reproductive success is directly related to the pollination efficiency, we investigated the reproductive system of these two species and the effect of the quality of the pollen transferred between flowers associated to the pollinators‟ behavior during the foraging, trying to understand the intrinsic factors related to mechanisms of self-in... (Complete abstract click electronic access below) / Doutor

La sélection sexuelle est une composante de la sélection naturelle qui génère des différences de succès reproducteur entre les individus par le filtre de la reproduction, et influence donc la transmission intergénérationnelle des gènes. Dans le cadre de cette thèse, l’effet de la variabilité de l’environnement hydraulique sur la sélection sexuelle chez la truite commune a été étudié à différentes échelles : intra- et inter-populationnelle. Des méthodes nouvelles permettant de mieux appréhender l’investissement reproducteur, ainsi que de décomposer l’effet des traits sur la fitness des individus en fonction des différentes étapes de la sélection sexuelle, ont été mises au point. Les expériences réalisées en milieux naturel et semi-naturel indiquent que la variabilité environnementale n’affecte pas le choix d’habitat de reproduction par les femelles, mais peut affecter l’investissement reproducteur dans la compétition par exemple, ainsi que les flux de gènes entre des populations génétiquement distinctes. Ces résultats permettent une première projection de l’évolution de la sélection sexuelle dans le contexte du changement climatique qui prédit l’augmentation de la variabilité hydrologique en zone tempérée. / As a component of natural selection, sexual selection produces variation in reproductive success throughout the reproductive period, and therefore impacts genes transmission between generations. During this PhD, the effect of variation in hydraulic environment on sexual selection in brown trout was investigated at both within and between populations scales. New approaches to improve estimation of reproductive investment, as well as models to decompose the effect of traits on individual fitness at each stage of sexual selection, were developed. Experiments in natural and semi-natural environments indicate that environmental variation does not impact reproduction habitat choice by females, but it can modify reproductive investment in some populations, as well as it can control gene flow between genetically distinct populations. These results help to understand the evolution of sexual selection in the broad context of increasing stochastic variations of river systems hydrology as predicted by climate change models in temperate areas.

Le lion de mer Australien a un cycle de reproduction non-annuel et asynchrone entre les colonies.Contrairement aux autres pinnipèdes, ce système unique offre l’opportunité aux mâles de se reproduiredans plusieurs sites lors d’une saison de reproduction. L’accès des mâles à plusieurs sites dereproduction pourrait contrecarrer le fort degré de structure génétique de population chez les femellesdûe à une fidélité extrême au site de reproduction. J'ai utilisé deux méthodes indépendantes maiscomplémentaires, moléculaire et acoustique, afin d’étudier la structure de la population et le systèmede reproduction. Pour l'analyse moléculaire, j'ai développé une banque de microsatellites spécifiques àl'espèce. Ces marqueurs ont été utilisés pour examiner le flux génétique des mâles dans les différentescolonies de reproduction, le succès reproducteur, et les taux de paternité inter- et intra-colonies. Deplus, j'ai mesuré la variation géographique dans les cris des mâles, ce qui représente une approchealternative pour mesurer les convergences/divergences entre colonies. J'ai montré que si les mâlesprésentent une certaine dispersion entre colonies, elle est limitée à une courte échelle en dépit del’opportunité des mâles de se reproduire dans différents sites. Les analyses acoustiques des cris demâles ont révélé des variations géographiques significatives entre colonies, qui ne reflètent pas lastructure génétique. Les analyses de paternité indiquent un faible taux de polygynie, la majorité desmâles ne produisant qu’un ou deux jeunes par saison. Des stratégies alternatives de reproduction(nomade ou sédentaire) sont présentes dans cette espèce, certains mâles se déplaçant activement entredifférentes colonies proches. Le système de reproduction unique du lion de mer Australien semblefortement influer à la fois les modalités de dispersion, mais aussi la structure de population et lesystème de reproduction. / The Australian sea lion has a non-annual and asynchronous breeding cycle across geographically closecolonies. In contrast to other pinnipeds, this unique reproductive system provides the opportunity formales to breed in different colonies during one breeding cycle. Male mating success across differentcolonies could counteract the high degree of structure driven by extreme site fidelity in females. I usedtwo, independent but complementary methods, molecular and acoustic to investigate their populationstructure and mating system. For molecular analysis I developed a species-specific microsatellitelibrary. These markers were used to examine the extent and rate of male mediated gene-flow acrossbreeding colonies but also to determine the breeding success and paternity both within and acrossspatially close colonies. Also, I investigated the geographical variation in male barking call. Thisrepresents an alternative approach to measure boundaries and relationships between colonies. Malesexhibit dispersal; however, this is limited to remarkably small scale in regards to the high potential fordispersal and opportunity to breed in different colonies. Acoustic analyses of the male barking callsrevealed significant geographical variation across sites; however this observed acoustic variation didnot reflect the genetic structure. Paternity analyses revealed that males display relatively modest ratesof polygyny with the majority of successful males siring only one or two pups per breeding cycle. Thepresence of alternative mating strategies (roaming vs staying) is apparent in this species with somemales actively moving and breeding between close colonies. It appears that the unique breedingbiology of Australian sea lion influences dispersal patterns, population structure and mating system.

Para avaliar a quantidade ótima de energia e recursos a ser investida em reprodução, um animal deve não só acessar informações sobre sua própria condição corporal, como acessar também informações sobre coespecíficos presentes no ambiente em que vive. Este trabalho investigou essas duas vias (endógena e exógena) de obtenção de informação. Utilizando como organismo modelo a aranha Paratrechalea ornata (Trechaleidae), uma espécie em que os machos produzem presentes nupciais, este estudo investigou: (a) se machos investem mais tempo de busca quando na presença de pistas químicas de fêmeas virgens; (b) se machos aumentam ou diminuem o investimento na produção do presente nupcial quando há pistas da presença de machos competidores; (c) se restrições alimentares impõem efeitos de curto e longo prazo sobre o comportamento de construção de presentes nupciais. Machos mostraram preferência por locais com pistas da presença de fêmeas, mas não diferenciaram pistas de fêmeas virgens e copuladas. Diante de pistas da presença de um macho competidor, machos produziram presentes de menor qualidade, com menos seda. Por fim, restrições alimentares provocam efeitos de curto e longo prazo no comportamento reprodutivo dos machos, diminuindo a frequência de produção do presente nupcial e o tamanho do presente construído. Conjuntamente, os três experimentos realizados mostram que machos de P. ornata utilizam tanto informações exógenas quanto endógenas para ajustar seu investimento em reprodução. A combinação das informações obtidas deve aumentar a eficiência no gasto de energia, maximizando o sucesso reprodutivo dos machos sem que isso prejudique a manutenção de seu organismo / To evaluate the optimal amount of energy and resources to be invested in reproduction, animals should not only obtain information about their own body condition, but they should also obtain information about conspecifics in the environment where they live. This study investigated these two ways (endogenous and exogenous) of acquiring information. Using as model organism the spider Paratrechalea ornata (Trechaleidae), a species in which males produce nuptial gifts, this study investigated: (a) if males invest more time searching for sexual partners in the presence of chemical cues of virgin females; (b) if males increase or decrease the investment in nuptial gift construction in the presence of chemical cues of competitor males; (c) if food deprivation imposes short- and long-term effects on nuptial gift construction. Males showed a preference for sites with cues of females, but they did not discriminate cues of virgin from cues of copulated females. When males detected cues of a male competitor, they produced lower quality gifts, with less silk. Finally, food deprivation imposed both short- and long-term negative effects on male reproductive behavior, decreasing the frequency of nuptial gift construction and also the size of the gift. Together, the three experiments show that males of P. ornata use both exogenous as endogenous information to adjust their investment in reproduction. The combination of information obtained may increase the efficiency in energy use, maximizing male reproductive success without compromising self maintenance