Submitted by (ana.araujo@ufrpe.br) on 2016-08-23T12:05:53Z No. of bitstreams: 1 Joanny Kelly Silva dos Santos Martins.pdf: 1467107 bytes, checksum: 51dc871b39b7f000a36a8445217f21da (MD5) / Made available in DSpace on 2016-08-23T12:05:54Z (GMT). No. of bitstreams: 1 Joanny Kelly Silva dos Santos Martins.pdf: 1467107 bytes, checksum: 51dc871b39b7f000a36a8445217f21da (MD5) Previous issue date: 2015-07-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The objective of this study was to survey the richness and abundance of pollinators, herbivores, ants and other predators associated to Ipomoea carnea subs. fistulosa, addition to assessing the indirect effects of florivory and the influence of patrolling ants associated with extrafloral nectaries on pollinators. The study was conducted durig eight months (August/2014 – March/2015) at the Fazenda Tamanduá, municipality of Santa Terezinha, Paraíba state, Brazil. It was quantified the number of pollinator visits in flowers with and without patrolling ants and flowers with simulated florivory. The number of herbivores per inflorescence and the occurrence of florivory were recorded in an experiment conducted from 5 am to 5 pm. Arthropods were collected monthly to record the richness and abundance. The temporal variation of florivory and production of buds, flowers and fruits were recorded monthly. The results of the effect of the damage and the presence of floral ants showed that both cause a decrease in the total number of visits. This can be explained by the fact that the floral damage was the loss of important floral attributes. Additionally, bees can evaluate the pattern of flower symmetry distance and detect predators corroborating the hypothesis that predators such as ants, remove pollinators of plant-pollinator systems. These effects may be considered risky for Ipomoea carnea subs. fistulosa, since it is a self-incompatible species and depends on the activity of pollinators for its fertilization. The composition of the arthropod fauna associated with plant species under study was represented by five groups: Araneae, Coleoptera, Hymenoptera, Diptera and Hemiptera. The highest abundance of herbivores occurred in months with low rainfall. The florivory rates were high, and more severe in the dry season. The number of ants associated to extrafloral nectaries increased directly with the abundance of herbivores over months. The multitrophic system studied showed complex, featuring a high richness of associated arthropods and various guilds among the trophic levels. During the dry season in the caatinga, Ipomoea carnea subs. fistulosa is one of the few species that persist with leaves and flowers, this enables the populations of I. carnea constitute major indicator spots resources for present herbivores. This may have been one of the main causes for the abundance of herbivores and floral herbivory rate was higher in the months with less precipitation. Overall the data suggest that abundance of herbivores was related to the quality and availability of plant resources, reflecting on other trophic levels as in a bottom-up model of trophic cascade. / O objetivo deste trabalho foi realizar um levantamento da riqueza e abundância dos polinizadores, herbívoros, formigas e predadores de insetos associados a Ipomoea carnea subs. fistulosa, bem como avaliar os efeitos indiretos da florivoria e a influência do patrulhamento de formigas associadas aos nectários extraflorais sobre os polinizadores. Este trabalho foi realizado em oito meses de coleta (agosto de 2014 a março de 2015) na Fazenda Tamanduá, no município de Santa Terezinha, PB. Foi quantificado o numero de visitas de polinizadores em flores com e sem patrulhamento de formigas e em flores com florivoria simulada. O número de herbívoros por inflorescência e a ocorrência de florivoria foi registrado em um experimento realizado das 5h às 17h. Os artrópodes foram coletados mensalmente para registro da riqueza e abundância. E a variação temporal da florivoria e produção de botões, flores e frutos foi registrada mensalmente. Os resultados do efeito do dano floral e presença de formigas mostraram que ambos provocam decréscimo no número de visitas totais. Isso pode ser justificado pelo fato de que o dano floral consistiu na perda de atributos florais importantes. Adicionalmente abelhas podem avaliar o padrão de simetria da flor à distância e detectar predadores corroborando com a hipótese de que predadores, tal como formigas, retiram polinizadores dos sistemas planta-polinizador. Estes efeitos para Ipomoea carnea subs. fistulosa podem ser considerados de risco, uma vez que é um espécie autoincompatível e depende da atividade dos polinizadores para que a sua fecundação ocorra. A composição da fauna de artrópodes associados a espécie vegetal em estudo foi representada por cinco grupos: Araneae, Coleoptera, Hymenoptera, Diptera e Hemiptera. O sistema multitrófico estudado se mostrou complexo, apresentando uma grande riqueza de artrópodes associados e variadas guildas dentre os níveis tróficos. Durante a estação seca na caatinga Ipomoea carnea subs. fistulosa, é uma das poucas espécies que persistem com folhas e flores, fato que faz com que as populações de I. carnea constituam grandes manchas indicadoras de recursos para os herbívoros presentes. Esta pode ter sido uma das principais causas para que a abundância de herbívoros e taxa de herbivoria floral tenha sido mais alta nos meses com menor precipitação. De maneira geral os dados sugerem que abundância de herbívoros respondeu a qualidade e disponibilidade dos recursos vegetais, refletindo nos demais níveis tróficos como em um modelo bottom-up de cascata trófica.

Orientadores: Andre Victor Lucci Freitas, Paulo Sergio Moreira Carvalho de Oliveira / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-15T21:52:40Z (GMT). No. of bitstreams: 1 Kaminski_LucasAugusto_D.pdf: 5366154 bytes, checksum: ed93bc172265e9ea406a60744f12536a (MD5) Previous issue date: 2010 / Resumo: Formigas constituem um dos mais proeminentes grupos de organismos terrestres em termos de diversidade, abundância relativa e biomassa animal. Sua importância se deve principalmente ao comportamento eusocial aliado a complexos sistemas de comunicação. A vegetação de áreas tropicais é rica em fontes de alimentos renováveis que induzem a visitação freqüente de formigas às plantas. Sobre a vegetação, as formigas podem atuar como predadoras e acarretar um forte efeito sobre a comunidade de insetos herbívoros. A presença de formigas sobre plantas pode afetar insetos herbívoros basicamente de duas formas: (1) limitando sua ocorrência na folhagem através de interações antagônicas (ex. agressão, predação) ou (2) propiciando espaços livres de inimigos naturais para herbívoros mirmecófilos (que mantêm associações simbióticas com formigas). Em Lepidoptera, a mirmecofilia é amplamente difundida em apenas duas famílias de borboletas (Lycaenidae e Riodinidae). Devido a grande importância da interação com formigas para a morfologia e biologia destas borboletas, acredita-se que grande parte da história evolutiva desses organismos, incluindo eventos de diversificação seja explicada pela mirmecofilia. No entanto, a maior parte da informação sobre borboletas mirmecófilas é baseada no conhecido para espécies das faunas Paleártica, Oriental e Australiana. Enquanto que a rica fauna de borboletas mirmecófilas Neotropicais permanece praticamente desconhecida. Dentre as cerca de 1.200 espécies de Lycaenidae Neotropicais, Parrhasius polibetes (Stoll) (Lepidoptera: Lycaenidae) foi reportada recentemente co-ocorrendo espaço-temporalmente com hemípteros mirmecófilos em Schefflera vinosa (Araliaceae). Neste trabalho são descritos novos aspectos relacionados à morfologia e história natural dos estágios imaturos de P. polibetes, incluindo custos da mirmecofilia, seleção de planta hospedeira, e benefícios da co-ocorrência com hemípteros trofobiontes. O ciclo de desenvolvimento de ovo a adulto é de aproximadamente 36 dias, e o estágio larval compreende quatro instares. Os ovos são depositados exclusivamente em tecidos reprodutivos (botões florais) das plantas hospedeiras. As larvas são polífagas, sendo registradas em 28 espécies em 16 famílias de plantas. A maioria da plantas hospedeiras de P. polibetes (78.57%) apresenta algum tipo de fonte de alimento líquido que promovem a visitação por formigas, sejam nectários extraflorais e/ou hemípteros produtores de exudatos. A partir do terceiro instar, as larvas são atendidas facultativamente por mais de quinze espécies de formigas em três subfamílias (Formicinae, Myrmicinae e Ectatomminae), principalmente formigas do gênero Camponotus Mayr. Assim como em outros Lycaenidae, as interações entre larvas e formigas são mediadas principalmente por uma glândula especializada (dorsal nectar organ) no sétimo segmento abdominal que produz recompensas calóricas para as formigas. Nesse sentido, é esperado que a produção dessas secreções acarrete em custos para as larvas. Para P. polibetes, é demonstrado que as formigas Camponotus crassus e Camponotus melanoticus apresentam diferentes intensidades de atendimento. C. melanoticus atende mais intensamente as larvas que C. crassus em condições de laboratório. Por sua vez, essa diferença pode acarretar em diferentes custos para as larvas. Por exemplo, quando atendidas por C. melanoticus demoram mais tempo para empupar. No entanto, o peso pupal e o tamanho dos adultos não são afetados pela diferença de atendimento, sugerindo que P. polibetes possui mecanismos compensatórios para minimizar os custos da mirmecofilia. Esta é a primeira demonstração de que diferenças específicas de intensidade de atendimento podem afetar parâmetros de desempenho de um inseto trofobionte. Em campo, é demonstrado através de experimentos pareados que o padrão previamente detectado de co-ocorrência espacial entre larvas de P. polibetes e hemípteros mirmecófilos é provocado por dois fatores: 1) fêmeas são capazes de detectar e ovipositar em plantas com associação membracídeos-formigas; 2) larvas que se desenvolvem perto da associação membracídeos-formigas sobrevivem melhor que larvas em plantas sem associação. Tal efeito ocorre porque a presença da interação entre membracídeos e formigas reduz a abundância de potenciais inimigos naturais das larvas (aranhas e vespas parasitóides). Além disso, as larvas são mais facilmente encontradas e atendidas pelas formigas que são recrutadas pelos membracídeos. Ou seja, a presença da associação membracídeos-formigas gera um "espaço livre de inimigos" sobre a planta hospedeira, que é explorado por P. polibetes. Esses resultados mostram que o enfoque tradicional no estudo de mutualismo, baseado em pares de espécies, é inapropriado para entender as pressões seletivas operando em sistemas multitróficos / Abstract: Ants are one of the most prominent groups of terrestrial organisms in terms of diversity, relative abundance and biomass. Their importance is due primarily to eusocial behavior combined with complex communication systems. Tropical foliage is rich in renewable feeding sources that promote ant foraging. As some of the most important predators on plants, ants strongly affect the herbivorous insects. The presence of ants on foliages may affect herbivores by two ways: (1) decreasing herbivore individual numbers due to antagonistic interactions (e.g., aggressiveness, predation); (2) providing an enemy-free space for myrmecophilous herbivores (i.e. those living in close associations with ants). The symbiotic interaction between Lepidoptera and ants is widespread but only among two butterfly families (Lycaenidae and Riodinidae). Due to the great importance of myrmecophily for the morphology and biology of these butterflies, it is supposed that much of the evolutionary history of organisms, including diversification, would be explained by their interactions with ants. However, most of the knowledge about the evolutionary ecology of lycaenids is based on studies of well known Palaearctic, Oriental, and Australian species while little is known about the rich Neotropical fauna, which contains nearly 1,200 species. Larvae of Parrhasius polibetes (Stoll) (Lepidoptera: Lycaenidae) co-occur spatially and temporally with honeydew-producing hemipterans on the host plant Schefflera vinosa (Araliaceae). This study describes new aspects of morphology and natural history of immature stages of P. polibetes, including costs of myrmecophily, host plant selection, and benefits of co-occurrence with hemipteran trophobionts. The development cycle from egg to adult is approximately 36 days, and includes four larval instars. The eggs are laid exclusively on reproductive tissues (flower buds) of the host plants. The larvae are polyphagous, and have already been recorded on 28 plant species from 16 families. Most of the observed host plants of P. polibetes present some kind of liquid reward potentially used by ants (78.57%), either honeydew-producing hemipterans and/or extrafloral nectaries. From the third instar on, the larvae are facultatively tended by more than fifteen ants species in three subfamilies (Formicinae, Myrmicinae, and Ectatomminae), especially ants of the genus Camponotus Mayr. As in other Lycaenidae, interactions between larvae and ants are mediated by a specialized gland (dorsal nectar organ) on the seventh abdominal segment, which produces caloric liquid rewards for ants. Therefore it is expected that the production of these secretions entail costs for the larvae. For P. polibetes, it is shown that Camponotus crassus and Camponotus melanoticus ants differ in the intensity of tending levels to larvae, with C. melanoticus presenting increased tending rates compared to C. crassus. This difference can lead to different costs for the larvae. For instance when tended by C. melanoticus, larvae take longer to pupate. However, the pupal weight and size of adults are not affected by ant tending, suggesting that P. polibetes has compensatory mechanisms to minimize the costs of myrmecophily. This is the first demonstration that specific differences in ant tending may affect performance parameters in an insect trophobiont. In the field, experiments involving the manipulation of ant-treehopper associations on host plants demonstrated that the spatial co-occurrence between P. polibetes caterpillars and honeydew-producing hemipterans is caused by two factors: 1) females are able to detect ant-treehopper associations on foliage before oviposition, and lay eggs in their vicinity; 2) larvae that develop near ant-tended treehoppers survive better than larvae on plants without such association. This effect occurs because the presence of ant-treehopper associations reduces the abundance of potential natural enemies (spiders and parasitoid wasps) of the caterpillars. Moreover, the larvae are more easily found by prospective tending ants that are recruited to nearby honeydew-producing treehoppers. That is, the presence of ant-treehopper associations creates an "enemy-free space" on the host plant, which is exploited by P. polibetes. These results show that a traditional pairwise approach is obviously inappropriate to assess the selective pressures operating within such multi-species systems / Doutorado / Ecologia / Doutor em Ecologia

Le microbiote a un impact majeur sur la physiologie de son hôte, cependant notre compréhension des mécanismes régulant la relation hôte/microbiote reste limitée. Nous utilisons un hôte modèle simple, la Drosophile, afin de répondre à ces questions. Durant mon doctorat, je me suis attaché à une étape particulière du cycle de vie de la Drosophile, sa phase larvaire. Celle-ci constitue sa phase de croissance et est influencée par le contexte nutritionnel. Le microbiote influence également cette étape: l’association avec la bactérie Lactobacillus plantarum tempère les effets de la carence alimentaire en soutenant un taux de croissance élevé et une maturation rapide, en modulant chez l’hôte l’activité de l’hormone Ecdysone et de l’insuline. En retour, L.plantarum bénéficie de l’association, les larvesassurant sa persistance dans la niche (la niche étant le substrat nutritif, les larves et les bactéries associées). Pour caractériser les mécanismes mis en jeu dans ce mutualisme nous avons décrit les réponses transcriptomiques et métaboliques de la larve et avons également étudié les perturbations métaboliques de la niche. Nos résultats mettent en avant l’optimisation de l’extraction des acides aminés du substrat comme facteur clef du mutualisme. L.plantarum active l’expression des protéases intestinales de l’hôte via la voie IMD/NF-κB, et bénéficierait en retour d’une quantité d’acides aminés plus importante assurant sa persistance. Ainsi, nos travaux contribuent à l’effort de compréhension desmécanismes régulant l’interaction hôte/microbiote et pourraient conduire à de nombreuses applications thérapeutiques, notamment dans le cadre de déséquilibres nutritionnels. / Symbiotic bacterial populations (also called the “microbiota”) have a dramatic impact on their host’s physiology. However, our understanding of the mechanisms shaping host/microbes mutualism remains limited. We took advantage of Drosophila tractability to characterize the host’s and the microbial factors engaged in mutualism. During my PhD, I focused on the impact of the microbiota during the Drosophila larval phase, which constitutes its juvenile growth period. Drosophila larval phase is influenced by nutrition, but also by symbiotic microbes: specific association with the bacterium Lactobacillus plantarum buffers the deleterious effects of nutrient scarcity on the host’s juvenile growth, by sustaining greater growth rates and hastening maturation. L.plantarum mediate these effects by modulating the activity of the steroid hormone Ecdysone and the Insulin/Insulin-like Signaling pathway in its host. In return, L.plantarum benefits from Drosophila presence, as larvae ensure its long-term persistence in the niche (the niche being the nutritive substrate, the larvae and the bacteria dwelling on it). To characterize the mechanisms engaged in this mutualistic relationship, we described the host’s transcriptomic and metabolic responses to L.plantarum presence and characterized the metabolic perturbations occurring in the niche. Our results put forward the optimization of amino-acids extraction from the nutritive substrate as a cornerstone of mutualism. L.plantarum activates the expression of the host’s digestive proteases via IMD/NF-κB signaling and would benefit in return from an enhanced AA availability, which would help sustaining its long-term persistence. Altogether, our studies contribute to the understanding of the mechanisms regulating host/microbiota interaction and could lead to numerous therapeutic applications, notably aiming at counteracting the deleterious effects of nutritional imbalances.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Syconia of fig trees present a diverse interaction with different groups of organisms. In this study we characterized insect community associated with three fig species in the region of Miranda/Abobral, Pantanal Sul matogrossense, obtaining data about species richness and abundance of these insects. We verified the specificity of these insects in regard to hosts and tested whether the size and number of flowers in the syconium determine species richness and abundance of insects in the syconia. We found 31 morpho-species of insects in the syconia of the three hosts. Syconia of Ficus obtusifolia had the highest richness (N = 18) and highest number of species co-occurring in the same syconia. Seven insect species were found sharing hosts. Mean abundance and species richness of insects in syconia of F. obtusifolia were significantly higher than in F. pertusa and F. luschnathiana what was related to the higher volume and number of flowers in the syconia of this fig tree. Our data may help in understanding the diversity and distribution of the insects associated with syconia of fig trees in the neotropical region. Papers that study Ficus insects associated system are important to show how these interactions occur in distinct fig trees and in different localities. / Sicônios de figueiras apresentam uma diversificada interação com diferentes grupos de organismos. Neste estudo, nós caracterizamos a comunidade de insetos associados a três espécies de figueiras na região do Miranda/Abobral, Pantanal Sul matogrossense, obtendo dados sobre a riqueza de espécies e a abundância destes insetos. Verificamos a especificidade destes insetos em relação aos hospedeiros e testamos se o volume e o número de flores dentro do sicônio determinam a riqueza de espécies e a abundância de insetos dentro dos sicônios. Foram encontradas 31 morfo-espécies de insetos nos sicônios das três espécies de figueiras analisadas. Sicônios de F. obtusifolia apresentaram a maior riqueza de espécies (S = 18) e maior número de espécies coocorrendo no mesmo sicônio. Sete espécies de insetos compartilharam hospedeiros. A média da abundância e da riqueza de espécies de insetos co-ocorrendo em sicônios de F. obtusifolia foi significativamente maior do que em F. pertusa e F. luschnathiana, fato que está ligado ao maior volume e número de flores nos sicônios desta figueira. Nossos resultados podem auxiliar no entendimento da diversidade e distribuição de insetos associados a sicônios de figueiras na região Neotropical. Trabalhos que abordam o sistema Ficus insetos associados são importantes para responder como estas interações acontecem em espécies de figueiras distintas e em diferentes localidades.

The inadequacy of arbitrarily classifying interactions between species as antagonistic, neutral or mutualistic has become clear in recent years. Both direct and indirect interactions between species can vary between mutualism and antagonism, depending on the intrinsic and extrinsic contexts of the interaction. This study investigated the characteristics of an ant-plant-homopteran interaction in southern Africa. The polyphagous homopteran Hilda patruelis (Tettigometridae) feeds primarily on the trunk-borne fruiting branches and figs of the Cape fig tree, Ficus sur, and produces honeydew which attracts tending ants. Ten of the sixteen ant species/species groups present on F. sur tended H. patruelis, with Pheidole megacephala the most frequent attendant. Ants attracted to F. sur by H. patruelis honeydew or other liquid food sources also preyed on insects on the tree, including adults of the small agaonid fig wasps whose larvae feed on the ovules in the developing figs. One fig wasp species (Ceratosolen capensis) is also the tree's only pollinator. No benefits to H. patruelis from being tended by ants were detected, either in terms of reduced parasitism, or predation by a lycaenid caterpillar. A P. megacephala colony foraging on a F. sur tree was found to receive a high proportion of its likely energy requirements from the tree, mainly in the form of H. patruelis honeydew, during periods when it was bearing fruit. It is probable that the H. patruelis-P. megacephala interaction constitutes a direct mutualism at times, but that benefits to the homopteran are intermittent or weak. Both H. patruelis and ants benefitted from F. sur, directly or indirectly, through the provision of food (and for some ants, nesting sites). The removal of phloem sap by H. patruelis did not detectably reduce the trees' reproductive output, either in terms of pollinator or viable seed production. The indirect effects of ant and H. patruelis presence on the F. sur trees were on average positive, as ants preyed disproportionately heavily on fig wasp species parasitic on or competing with the pollinator, thus increasing pollinator production. Effects of ant presence on seed production were not investigated, but have been demonstrated as beneficial elsewhere. However, there is great varatlon both in the composition of the wasp fauna arriving to oviposit at different crops, and in ant densities per fig, on several temporal and spatial scales. This results in high variability in the effects of ants on the pollinator and, through it, the tree, from positive to zero and potentially even negative. Despite this conditionality of beneficial outcomes for the tree, the mean effect of ants on the F. sur population studied was to increase pollinator production by up to nearly 20%. This study is among the few to have demonstrated an overall benefit to a plant of having homopteran-tending ants present on it.

The fig–fig wasp interaction is a classic example of obligate mutualism and coevolution. It is also a nursery pollination mutualism and supports a diversity of exploiter/parasite/non-pollinating fig wasp species. Mutualists and exploiters comprise the fig wasp community. All the wasp community members are obligately dependent on the fig syconium (a globular closed structure comprising of hundreds to thousands of uniovulate florets) for completing their life cycle. The fig florets can be sessile (without a stalk) or pedicellate (stalked) and can support a community comprising 3–30 wasp species. Fig wasps can access the floral resources for oviposition directly by entering into the syconium (internal oviposition) or by penetration of the syconium surface (external oviposition). Most studies on the fig–fig wasp interaction have investigated the stability of the interaction, pollination biology, pollen dispersal, co-evolution or the effect of exploiters on this mutualism. However, studies dealing with community ecology and species coexistence mechanisms in these communities are rare. Factors contributing to coexistence of mutualists and exploiters in a fig wasp community were studied using a reasonably speciose fig wasp community associated with Ficus racemosa in south India. The wasp community of Ficus racemosa comprises a single species of pollinator and six species of exploiters; together they represent three genera of fig wasp species. The community members show differences in their feeding habit; they could be 1) gallers (feed on floral tissue after pollination and/or after inducing abnormal tissue development of the floret that is also called the gall), 2) inquilines (feed on gall tissue but cannot induce galling; survive by feeding on gall tissue and starving the host larva to death), or 3) parasitoids (lay eggs in or on developing offspring of a galler or inquiline species; develop by feeding on host tissue). Resource partitioning across temporal and spatial axes on this fig wasp community have been quantified. Ovipositor traits of each community member were also investigated since variation in ovipositor traits might facilitate resource partitioning. Finally, the role of life-history traits in species coexistence in this community was also explored. Temporal resource partitioning among members of the fig wasp community was studied (1) across the resource phenology, i.e. over the development phases of the fig syconium, and (2) on a diel scale. The seven members of the wasp community were found to partition their oviposition periods across fig syconium development phenology; some species used very young syconia (soft and smaller in size) for oviposition whereas others used mature (hard and bigger in size) syconia for oviposition. The first species to colonise the syconia were gallers and these were followed by parasitoids in a definite oviposition sequence. Pollinators arrived concurrently with an exploiter galler species and had the shortest oviposition window in terms of days. Although fig wasps are known to be largely diurnal, night oviposition in several fig wasp species was documented for the first time. Wasp species showed a peak in their activity period across the diel cycle and phenology. This is probably the first study to simultaneously investigate temporal partitioning across the syconium phenology as well as the diel scale in a fig wasp community. Partitioning of syconium space was investigated by quantifying the quality (type of floret—sessile or pedicellate) of floral resources. The number of individuals of each species developing in a syconium was quantified along with host accessibility during oviposition by each wasp species. The association between community members developing within a syconium was also tested. The differential occupancy of florets by each species based on their distance from the base of the syconium was evaluated. For the first time the relative distribution of males and females of the entire fig wasp community was quantified. The wasp community members used similar types of florets for oviposition. Seeds were found mostly in sessile florets and wasps were present in large numbers in pedicellate florets. Except for one wasp species, all others occurred uniformly within the syconium with respect to the distance from the base of the syconium. Species distribution models revealed higher prediction ability for the location of mutualists (seed and pollinator) within the syconium compared to exploiters. Within a syconium, all species pairs exhibited positive associations indicating either an absence of or low competitive exclusion. Some florets were modified by their gall occupants such that they were longer in length indicating the possibility of creation of an enemy-free zone by the gall occupant. Yet, most florets were accessible to ovipositing wasps based on ovipositor lengths and flexibility. The probability of finding a male decreased with increase in floret length when all wasp species were grouped together; however, this trend did not hold true when males and females of species were tested individually. Based on these results, the fig wasps of F. racemosa could be grouped into—(1) Early-arriving galler species which used immature florets, inducing large galls that protruded into the cavity, and with fewer individuals per syconium, (2) Galler species arriving concurrently with the pollinator, inducing galls that were morphologically indistinguishable from those of the pollinator, and with many individuals developing per fig syconium, and (3) Parasitoids and/or inquilines of the galler species, with variable abundance per syconium. Thus, these results show that the wasp species do not clearly partition floral resources between syconia and within syconium but they can modify their oviposition sites and also differ in the proportion of florets within a syconium used for oviposition. Oviposition sites of the fig wasps can be reached only by using their ovipositor. The resources for oviposition are hidden and hence might require tools for resource location and utilisation. The frequency and diversity of sensilla on the ovipositor, as well as ovipositor structure (morphology and sclerotisation of the tip) was documented for the entire wasp community. The internally-ovipositing pollinator had the simplest ovipositor, negligible sclerotisation and only one type of sensillum on its ovipositor; the externally ovipositing exploiter species had teeth on their ovipositors, sclerotisation and various types of ovipositor sensilla. Ovipositor sclerotisation and lateness of arrival for oviposition in syconium development were positively correlated. Ovipositor teeth height increased from gallers to parasitoids. Presence of different types of sensilla was noted which included mechano- and chemosensilla, as well as combined mechano-chemosensilla. Chemosensilla were most concentrated at ovipositor tips while mechanoreceptors were more widely distributed. Ovipositor traits of one putative parasitoid/inquiline species differed from those of its syntopic galler congeners and clustered with those of parasitoids within a different wasp subfamily. Thus ovipositor tools show lability based on adaptive necessity, and are not constrained by phylogeny. Life-history traits such as fecundity, pre-adult and adult lifespan were studied for each wasp member of the community. Trade-offs in life-history traits were also investigated. Interspecific variation in life-history traits was observed. Gallers were pro-ovigenic (all eggs were mature upon adult emergence) whereas parasitoids were synovigenic (eggs matured progressively during adult lifespan). Initial egg load was correlated with body size for some species, and there was a trade-off between egg number and egg size across all species. Although all species completed their development and left the syconium concurrently, they differed in their adult and preadult lifespans. Providing sucrose solutions increased parasitoid lifespan but had no effect on the longevity of some galler species. While feeding regimes and body size affected longevity in most species, an interaction effect between these variables was detected for only one species. Life-history traits of wasp species exhibited a continuum in relation to their arrival sequence at syconia for oviposition during syconium development, and therefore reflected their ecology. The largest number of eggs, smallest egg sizes, and shortest longevities were characteristic of the earliest-arriving galling wasps at the smallest, immature syconia; the converse characterised the later-arriving parasitoids at the larger, already exploited syconia. Thus life-history is an important correlate of community resource partitioning and can be used to understand community structure. The comparative approach revealed constraints and flexibility in trait evolution. This is probably the first comprehensive study of life-history traits in a fig wasp community.

Orientadores: Sergio Furtado dos Reis, Marcus A. M. de Aguiar / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-07T21:09:47Z (GMT). No. of bitstreams: 1 GuimaraesJunior_PauloRoberto_D.pdf: 2044862 bytes, checksum: c00f35ae5e3827324339e695a7aa0624 (MD5) Previous issue date: 2006 / Resumo: INTRODUÇÃO: mutualismos são interações entre espécies diferentes que beneficiam os indivíduos envolvidos. Em uma comunidade ecológica, mutualismos tais como interações entre plantas e polinizadores e entre plantas e dispersores de sementes podem ser descritas como uma rede. O estudo dessas redes de interações levou à descrição de duas propriedades estruturais gerais: (1) a probabilidade de se encontrar uma espécie com k interações decai seguindo uma lei de potência com truncamento exponencial e (2) aninhamento. Essas duas propriedades estão, aparentemente, ausentes em interações entre predadores e presas, as chamadas teias tróficas. OBJETIVOS: contribuir para a compreensão dos processos subjacentes aos padrões observados em redes mutualísticas e investigar o grau de generalização desses padrões. PRINCIPAIS RESULTADOS: ¿ A lei de potência truncada que caracteriza a distribuição do grau de redes mutualísticas pode ser explicada por condições iniciais aleatórias e por processos associados à diferença de riqueza entre plantas e animais. ¿ A estrutura aninhada de uma rede mutualística é parcialmente explicada por diferenças entre as abundâncias das espécies. ¿ Problemas de resolução taxonômica característica de estudos sobre teias tróficas, mas pouco comuns no estudo de mutualismos, explicam as diferenças nas distribuições do grau desses dois tipos de redes ecológicas. A ausência de aninhamento, todavia, não é explicada por este problema de resolução. ¿ As redes que descrevem outros dois mutualismos, as interações entre limpadores e clientes em recifes de corais e entre formigas e plantas produtoras de néctar extrafloral, são aninhadas. PRINCIPAIS CONCLUSÕES: a forma da distribuição do grau observada em mutualismos é esperada por processos simples e gerais. O aninhamento é uma propriedade geral de mutualismos em comunidades ricas de espécies / Abstract: Not informed. / Doutorado / Doutor em Ecologia

The Johannesburg, Cottesloe, Gas Works is located within the Witwatersrand zone of integration, between the University of Johannesburg and Witwatersrand. According to the Johannesburg Metropolitan Open Space System (JMOSS), there is a high priority to link secondary open spaces such as the educational premises. The Johannesburg Gas Works forms part of Jozi’s cityscape and the three remaining 45meter high gas cylinders represents a visual iconic landmark in the city. The site is currently inaccessible. The aim of this dissertation will be to determine the manner in which a user experience can be created as a palimpsest of meaning between the tangible and intangible elements on site. This implies a dialogue between the polluted areas of industrial waste, the layers of historical significance and the remnants of nature. The dissertation specifically focuses on awareness creation through the landscape experience on a post-industrial site of the associated social exploitation and environmental contamination. The Open Narrative approach will be used as part of the methodology which implies multiple interpretations by users and recognizes the presence of embedded narratives inscribed by past and future cultural practices and natural processes. A new narrative is inscribed onto the site and provides multiple experiences with each visit to the site through a phased intervention that opens up areas and processes for experience as they become decontaminated. To facilitate the palimpsest of tangible and intangible meaning, the user experience is proposed to consist of three realities: a lower, in-between and upper reality with increasing elements of transience. The essence of the design and its programme becomes mutualistic (as opposed to exploitative), based on the principles outlined by Klein (2014) namely, “interdependence, reciprocity and cooperation”. The goal of the design intervention is to foster a renewed community identity and social and environmental health through the range of active and passive activities proposed but also through the particular experiences that open up the site for renewed interpretation to all users. The dissertation demonstrates that new meanings can be applied to spaces that once posed a cultural limitation. A mutualistic relationship between the site and the people can and should co-exist. / Mini Dissertation ML(Prof)--University of Pretoria, 2018. / Architecture / ML(Prof) / Unrestricted

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京都大学 / 0048 / 新制・課程博士 / 博士(人間・環境学) / 甲第19070号 / 人博第723号 / 新制||人||173(附属図書館) / 26||人博||723(吉田南総合図書館) / 32021 / 京都大学大学院人間・環境学研究科相関環境学専攻 / (主査)教授 市岡 孝朗, 教授 加藤 眞, 教授 瀬戸口 浩彰 / 学位規則第4条第1項該当 / Doctor of Human and Environmental Studies / Kyoto University / DGAM