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Submitted by Dominick Jesus (dominickdejesus@hotmail.com) on 2016-02-04T17:38:54Z No. of bitstreams: 2 Dissertação_Josenir Teixeira Câmara.pdf: 7718395 bytes, checksum: 44faf0cd21fa5932fb6c46e9714c2c25 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-02-04T17:38:54Z (GMT). No. of bitstreams: 2 Dissertação_Josenir Teixeira Câmara.pdf: 7718395 bytes, checksum: 44faf0cd21fa5932fb6c46e9714c2c25 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2012-02-14 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Opeatocerata Melander is revised based on primary types of the following species: O. rubida (Wheeler and Melander, 1901) (holotype female), O. stubbsi Smith, 1989 (holotype male), O. cooperi Smith, 1989 (holotype female), O. lopesi Smith, 1989 (holotype male), O. melanderi Câmara and Rafael, 2011 (holotype male) and O. trilobata Câmara and Rafael, 2011 (holotype male). It has a Neotropical distribution, the specimens varying from 2 and 5 mm in length and predominantly yellow. Here it is been described and illustrated 15 new species: Opeatocerata agudeloi sp. nov. (Colombia, Amazonas), O. ampullaria sp. nov. (Brazil, Amazonas), O. bare sp. nov. (Brazil, Amazonas), O. brasiliensis sp. nov. (Brazil, Goiás, Mato Grosso, Pará), O. cylindrophallus sp. nov. (Brazil, Mato Grosso), O. curvipenis sp. nov. (Costa Rica, La Suiza, San Mateo), O. hadrophallus sp. nov. (Brazil, Amazonas), O. hypandriociliaris sp. nov. (Brazil, Pará), O. megalophallus sp. nov. (Costa Rica, San Mateo, Guanacaste), O. mourai sp. nov. (Brazil, Amazonas), O. nhamunda sp. nov. (Brazil, Pará), O. smithi sp.nov. (Brazil, Amazonas), O. spinipenis sp. nov. (Brazil, Amazonas), O. tanimboca sp. nov. (Colombia, Amazonas; Brazil, Amazonas) and O. zuleideae sp. nov. (Brazil, Amazonas). An illustrated dichotomous key and maps with geographical records are presented. Phylogenetic analysis demonstrated the monophyly of Opeatocerata and it is presented a phylogenetic relationships hypothesis among species. / Opeatocerata Melander é revisado a partir do estudo dos tipos primários das seguintes espécies: O. rubida (Wheeler e Melander, 1901) (holótipo fêmea), O. stubbsi Smith, 1989 (holótipo macho), O. cooperi Smith, 1989 (holótipo fêmea), O. lopesi Smith, 1989 (holótipo macho), O. melanderi Câmara e Rafael, 2011 (holótipo macho) e O. trilobata Câmara e Rafael, 2011 (holótipo macho). É de distribuição Neotropical, suas espécies variam entre 2 e 5 mm de comprimento e são predominantemente amarelas. São descritas e ilustradas 15 espécies novas: Opeatocerata agudeloi sp. nov. (Colômbia, Amazonas), O. ampullaria sp. nov. (Brasil, Amazonas), O. bare sp. nov. (Brasil, Amazonas), O. brasiliensis sp. nov. (Brasil, Goiás, Mato Grosso, Pará), O. cylindrophallus sp. nov. (Brasil, Mato Grosso), O. curvipenis sp. nov. (Costa Rica, La Suiza, San Mateo), O. hadrophallus sp. nov. (Brasil, Amazonas), O. hypandriociliaris sp. nov. (Brasil, Pará), O. megalophallus sp. nov. (Costa Rica, San Mateo, Guanacaste), O. mourai sp. nov. (Brasil, Amazonas), O. nhamunda sp. nov. (Brasil, Pará), O. smithi sp.nov. (Brasil, Amazonas), O. spinipenis sp. nov. (Brasil, Amazonas), O. tanimboca sp. nov. (Colômbia, Amazonas; Brasil, Amazonas) e O. zuleideae sp. nov. (Brasil, Amazonas). São apresentados uma chave dicotômica ilustrada e o mapa com os registros geográficos das espécies. A análise filogenética comprovou a monofilia do gênero e é apresentada uma hipótese de relacionamento filogenético entre as espécies.

Les montagnes sont des hotspots de biodiversité dont les réseaux plantes-pollinisateurs constituent un élément central, et où les conséquences du réchauffement climatique sont déjà avérées. Malgré le nombre colossal d’espèces potentiellement affectées par la destructuration du mutualisme entre les angiospermes et leurs pollinisateurs dans ces écosystèmes, les patrons spatio-temporels des communautés de pollinisateurs le long des gradients altitudinaux sont toujours méconnus. La première partie de ce travail propose une analyse des effets de l’altitude et de la phénologie sur l’abondance et la diversité des insectes anthophiles le long d’un gradient altitudinal de 1700 m. Nous montrons qu’il existe une structuration altitudinale et trophique entre les principaux ordres de pollinisateurs (hyménoptères, diptères, coléoptères), avec une nette prédominance des diptères dès 1500 m d’altitude qui s’amplifie jusqu’à la limite supérieure du gradient (2700 m). Ces diptères appartiennent principalement à trois familles (Anthomyiidae, Empididae, Muscidae) qui se structurent également le long du gradient par l’altitude, la phénologie et le choix des plantes visitées. Leur biologie, efficacité pollinisatrice comprise, est encore largement méconnue. Dans un second temps, nous étudions l’écologie de la pollinisation et les causes évolutives du succès d’un groupe central de ces communautés anthophiles, les Empidinae. Nous avons mesuré 1) leur importance relative dans un réseau plantes-visiteurs à l’étage subalpin et 2) leur efficacité pollinisatrice par rapport à celles des autres visiteurs pour une plante de ce réseau (Geranium sylvaticum L.). Nous montrons que les visites d’une grosse espèce d’Empis produisent le même nombre de graines que celles de l’abeille domestique (Apis mellifera L.), pollinisatrice réputée très efficace. Ces résultats suggèrent un rôle majeur des gros Empidinae dans la pollinisation des plantes alpines. Pour comprendre le rôle de la floricolie dans la diversification des Empidinae et l’origine de leur abondance en altitude, nous avons construit une phylogénie moléculaire mondiale sur la base de 4 marqueurs et pour plus de 210 espèces. La plupart des clades d’Empidinae contiennent des espèces qui occupent diverses altitudes, indiquant qu’il n’y a pas de conservatisme de niche impliqué dans leur distribution le long du gradient. L’association angiospermes-Empidinae remonte à la période de fin de radiation des angiospermes et semble, par l’intermédiaire de l’allongement de la trompe, avoir favorisé la radiation évolutive de certains clades en parallèle avec celles des plantes à fleurs. Leur large distribution altitudinale et leur capacité à visiter des morphotypes floraux inaccessibles à d’autres floricoles pourraient leur conférer une importante résistance aux changements globaux. / Mountains are biodiversity hotspots, where the effects of global warming have already been demonstrated in numerous studies. Plant-pollinator networks are a central element of these ecosystems, but, despite the tremendous number of species potentially affected by the disruption of this mutualism, spatial and temporal patterns of pollinator communities along altitudinal gradients are still poorly known. The first part of this work analyses the effects of elevation and phenology on the abundance and diversity of anthophilous insects along a 1700 m altitudinal gradient. I show that the main orders of pollinators (Diptera, Hymenoptera, Coleoptera) are structured by elevation and foraging preferences, with an increasing predominance of flies from 1500 m altitude up to 2700 m, the upper limit of the gradient. Most of these fly species belong to four families (Anthomyiidae, Empididae, Muscidae and Syrphidae) which also segregate along the gradient according to altitude, phenology and the choice of flowering plants they visit. The systematics and biology of these taxa, including their pollination efficiency, are still largely under-investigated. Second, I studied the pollination ecology and the evolutionary causes of the success of empidine dance flies (Empidinae), a central group in these anthophilous communities. I measured 1) their relative importance in the plant-visitor network of a subalpine meadow; and 2) the pollinating effectiveness of their visits to Geranium sylvaticum L. relative to the other visitors. Visits by large species of Empis produced the same number of seeds as those by the domestic bee (Apis mellifera L.), a highly effective pollinator. Such results suggest a major role of large empidines in the pollination of alpine plants. To understand the role of anthophily in Empidinae diversification and the origins of their abundance at altitude, I built a worldwide molecular phylogeny for the subfamily. The resulting cladogram includes 212 species for which four molecular markers were sequenced (28S D1-D2, D4-D5, 16S mtDNA, COI). Most clades of Empidinae contain species occupying various altitudes, indicating that there is no phylogenetic niche conservatism involved in their distribution along the gradient. The association between Empidinae and Angiosperms dates back to the end of the angiosperm radiation and seems, through the lengthening of the proboscis, to have favoured the evolutionary radiation of several clades in parallel with flowering plants. Their wide altitudinal distribution, combined with their ability to visit floral morphotypes inaccessible to other anthophilous insects, could confer them a strong resistance to global changes.

Elaborate morphological ornaments can evolve if they increase the reproductive success of the bearer during competition for mates. However, ornament evolution is incredibly rare in females, and the type and intensity of selection required to develop female-specific ornamentation is poorly understood. The main goals of my thesis are to clarify the relationship between the type and intensity of sexual selection that drives the evolution of female ornamentation, and investigate alternative hypotheses that might be limiting or contributing to the development of female ornaments. I investigated the ecology and evolution of female-specific ornaments within and between species of dance flies from the subfamily Empidinae (Diptera: Empididae). The dance flies display incredible mating system diversity including those with elaborate female-specific ornaments, lek-like mating swarms, aerial copulation and nuptial gift giving. To elucidate the form of sexual selection involved in female-ornament evolution, I experimentally investigated the role of sexual conflict in the evolution of multiple female- specific ornaments in the species Rhamphomyia longicauda. Through manipulative field experiments, I found that variation in the attractiveness of two ornaments displayed by females indicates that sexual conflict, causing a coevolutionary arms race, is an important force in the evolution of multiple extravagant female ornaments. Using R. longicauda again, I tested for a role of functional load-lifting constraints on the aerial mating ability of males who paired with females displaying multiple large ornaments. I found no evidence of functional constraints influencing the mating opportunities of elaborately ornate females, but instead discovered a relationship consistent with positive assortative mating for mass. Biased sex ratios are predicted to increase the intensity of sexual selection in a population, which in turn, is predicted to influence the evolution of ornamentation. I measured the incidence and prevalence of vertically transmitted symbiotic bacteria that has been observed to distort the sex ratio in other Dipteran hosts. While my survey revealed that symbionts occur at high incidence and variable prevalence across dance fly hosts, I found no effect of symbiont infection levels on population sex ratios, or female- specific ornament evolution. Further investigation into the relationship between sex ratios and female-ornament evolution using the comparative method revealed that the operational sex ratio (OSR) of a population did not predict continuous measures of female ornamentation across species. However, female-ornament evolution did predict male relative testis investment across species indicating that female ornaments likely indicate increased levels of polyandry. My thesis reveals that sexual selection theory developed to describe male-specific ornament evolution cannot readily be translated to apply to females. I show that male mate choice, rather than functional constraints or ecological associations with bacteria, is likely driving the evolution of female-specific ornaments. I also identify sexual conflict as an important selective force in the evolution of female-specific ornaments.

Elaborate sexual ornaments evolve because mate choice exerts strong sexual selection favouring individuals with high levels of ornament expression. Consequently, even at evolutionary equilibrium, life history theory predicts that ornamental traits should be under directional sexual selection that opposes contrasting selection to reduce the costs associated with their maintenance. Otherwise, the resources used to maintain ornaments should be used to improve other life history functions. Elaborate female ornaments have only evolved in a few species, despite females commonly experiencing strong sexual selection. One explanation for this rarity is that male preferences for female ornaments may be self-limiting: females with higher mating success become less attractive because of the lower paternity share they provide to mates with every additional sperm competitor. The unusual species in which female ornaments do occur can provide rare insight into how selection can favour the expression of expensive characters in females despite their costs. The main goal of my thesis was to determine how sexual selection acts on exaggerated sexual ornaments, and give new insight into how these ornaments may have evolved, in spite of the self-limiting nature of selection on male preferences. To determine the strength of sexual selection acting on female ornamentation in dance flies, we developed new microsatellite markers to assess polyandry rates by genotyping stored sperm in wild female dance flies. We first used polyandry rates to determine whether ornament expression was associated with higher mating success in female Rhamphomyia longicauda, a species that has evolved two distinct and exaggerated female ornaments. Contrary to our predictions, we found no evidence that females with larger ornaments enjoy higher mating success. We then compared polyandry rates in R. longicauda to those of two other species of dance fly, one (Empis aestiva) that has i independently evolved female ornaments on its legs, and another (E. tessellata) that does not possess any discernable female ornaments. We also estimated the opportunity for sexual selection, which we found to be similar and relatively low in all three species. Moreover, the standardized sexual selection gradients for ornaments were weak and non-significant in all three species. Females with more elaborate ornaments, in both within- and cross-species comparisons, therefore did not enjoy higher mating success. Overall, these results suggested that sexual selection operates rather differently in females compared to males, potentially explaining the general rarity of female ornaments. Our amplifications of stored sperm were able to reveal more than just mate numbers. We developed new methods to study patterns of sperm storage in wild female dance flies. We investigated how the skew in sperm genotypes from mixed sperm stores changed with varying levels of polyandry. Our data suggested that sperm stores were dominated by a single male in R. longicauda, and that the proportion of sperm contributed by this dominant male was largely independent of the number of rival males’ sperm present in the spermatheca. These results were consistent with the expectation of males using sperm ‘offence strategies’ in sperm competition and that the most successful male is likely to be the female’s last partner before oviposition. As a whole, my thesis contributed new molecular resources for an understudied and fascinating group of organisms. It exploited these new resources to provide the first estimates of lifetime mating success in several related species, and suggested that the general prediction that ornament expression should covary with sexual selection intensity does not seem to hold in this group. Instead, both the unusual prevalence of ii ornaments and the inconsistent evidence for sexual selection that sustains them in dance flies may owe their existence to the confluence of two important factors. First, the conditions under which sperm competition occurs: as last male precedence is likely, males are selected to prefer the most gravid females to secure a high fraction of her offspring’s paternity as they are unlikely to mate again before oviposition. Second, potent sexually antagonistic coevolution between hungry females and discerning males: females have evolved ornaments to disguise their stage of egg maturity to receive the benefits of nuptial gifts, while males face the challenge of distinguishing between gravidity and ornamentation in females.