Neotyphodium are fungal endosymbionts of grasses that reproduce asexually by infecting the hosts seed. This relationship has traditionally been considered mutualistic, with the fungus improving host fitness by alleviating important stresses. To determine the importance of biotic and abiotic stresses in mediating the endophyte-grass interaction, I investigated the relationship between grazing pressure by collared pikas and Neotyphodium sp. infection frequency in the grass Festuca altaica in an alpine meadow. I conducted a factorial design experiment combining endophyte infection, grazing history, fungicide and fertilizer. Leaf demography and herbivory damage were monitored every two weeks. In areas with chronic grazing history, infected plants were significantly less productive than uninfected tussocks, but there was no difference at low grazing history. There was no effect of infection on the likelihood of herbivory. Contrary to predictions of the mutualism theory, the Neotyphodium sp. / F. altaica symbiotum varied from parasitic to neutral across our gradient of interest. / Ecology

Thesis(M.S.)--Auburn University, 2005. / Abstract. Includes bibliographic references.

Thesis (Ph. D.)--Oregon State University, 2008. / Printout. Includes bibliographical references. Also available on the World Wide Web.

Thesis (PhD) - Australian Graduate School of Entrepreneurship, Swinburne University of Technology - 2008. / Submitted for the degree of Doctor of Philosophy, Australian Graduate School of Entrepreneurship, Swinburne University of Technology, 2008. Includes bibliographical references (p. 212-236).

Thesis (Ph. D.)--University of Wyoming, 2007. / Title from PDF title page (viewed Feb. 9, 2009). Includes bibliographical references.

Mutualismos entre plantas e polinizadores estão organizados em redes de interação que envolvem muitas espécies. Em última instância, o que determina a ocorrência das interações entre plantas e polinizadores são as características dos dois grupos de espécies. O comportamento social pode ser uma das caraterísticas chave na organização das interações em sistemas de polinização. Investigamos se a presença de polinizadores com comportamento social em redes de polinização está associada a diferentes padrões estruturais, e se polinizadores com níveis crescentes de complexidade no comportamento social são mais importantes pra estrutura dessas redes. Encontramos que a variação na proporção de espécies sociais não altera a estrutura de redes de polinização. Encontramos também que espécies com comportamento social são, em média, mais importantes para a estrutura de redes de polinização do que espécies solitárias. Nossos resultados corroboram resultados anteriores que sugerem que redes mutualísticas tem estruturas invariantes. Nossos resultados sugerem ainda que o papel estrutural mais proeminente das espécies sociais está associado à sua maior abundância. Incluir aspectos da história natural das espécies e das interações em estudos de redes ecológicas, nos permitirá fazer inferências cada vez mais assertivas sobre a importância funcional das espécies em comunidades / Mutualisms between plants and pollinators are organized in interaction networks that involve many species. Ultimately, what determines the occurrence of interactions among plants and pollinators are the traits of both groups of species. Social behavior can be a key trait on the organization of interactions between plants and pollinators. Here, we investigated if the presence of pollinators with social behavior in pollination networks is associated to different structural patterns, and if pollinators with increasing levels of complexity in social behavior are more important for network structure. We found that the presence of social pollinator species does not affect the structure of pollination networks. We also found that species with social behavior are, on average, more important for network structure than solitary species. Our results reinforce past studies that suggested that the structure of mutualistic networks has invariant structural properties. Our results also suggest that the more prominent role occupied by pollinators with social behavior is associated to these species\' large abundances. Including natural history information about species and about species interactions on the study of ecological networks will allow us to make more assertive inferences on the functional roles species occupy in ecological communities

No amplo domínio da discussão historiográfica que cobre o tema da população livre de cor ou dos pobres livres, o trabalho se propõe a discutir a inserção social de indivíduos oriundos de setores populares na primeira metade do século XIX na Bahia, debruçando-se especialmente sobre a experiência de homens e mulheres de cor preta, livres ou libertos, nascidos na América, responsáveis por fundar e transformar experiências de mutualismo popular na Bahia do século XIX. A investigação se concentra nas conexões entre as tradições religiosa e secular da ajuda mútua popular promovida por negros no Brasil, por meio da ênfase no estudo das decisões e dos modelos institucionais adotados por integrantes de uma irmandade de pretos fundada em 1832 e de uma sociedade mutual de cor (1851). Saída de uma dissidência entre os irmãos, a Sociedade Protetora dos Desvalidos foi, até onde se sabe, a única mutual autorizada a funcionar oficialmente como uma sociedade de cor, num período de não reconhecimento, e de repressão, da identidade racial de pretos pelo Estado brasileiro. / This thesis aims to discuss the experience of free colour people in Bahia nineteenth century, on the vast theme of popular social mobility that recent historians have been facing in Brazilian historiography. These individuals were black, american born, free or freed men and women, and they helped to create and to change patterns of popular mutual aid in Bahia nineteenth century. This research focuses on connexions between religious and secular traditions of mutual aid of black individual associations by analysing institutional models and strategic decisions made by the members of a black lay sodality founded in 1832 and of a black mutual society, created in 1851. The Sociedade Protetora dos Desvalidos (1851) resulted from a dissidence within the sodality and it was the sole mutual black association officially authorized by the government within an age when black racial identity was not likely to be recognized by Brazilian state.

Orientador: Paulo Sérgio Moreira Carvalho de Oliveira / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-26T11:02:39Z (GMT). No. of bitstreams: 1 Mota_LuisaLimae_M.pdf: 2431693 bytes, checksum: af49f66454904ecb2d987348646ea0e0 (MD5) Previous issue date: 2014 / Resumo: A escolha do local de oviposição tem grande influência na aptidão das fêmeas de Lepidoptera, uma vez que as larvas têm mobilidade restrita. Pistas químicas, visuais e/ou táteis provindas da planta hospedeira costumam ser utilizadas, mas também são importantes a presença de inimigos naturais ou parceiros mutualistas. No caso de espécies mirmecófilas, a oviposição pode ser mediada pelas formigas atendentes, mas pouco se sabe sobre como as borboletas percebem as formigas e as utilizam como sinal. Parrhasius polibetes, um licenídeo polífago que apresenta mirmecofilia facultativa, é comumente encontrada em Schefflera vinosa (Araliaceae), uma planta que também pode abrigar agregações do membracídeo Guayaquila xiphias. P. polibetes e G. xiphias podem ser atendidas pelas mesmas formigas, e larvas de P. polibetes tem sua sobrevivência aumentada quando ocorrem próximas às associações G. xiphias + formigas, e as borboletas adultas preferem ovipositar em ramos onde a associação está presente, embora não se conheça qual sinal é utilizado para essa escolha. Este trabalho teve por objetivo investigar se P. polibetes reconhece visualmente a associação e a utiliza como pista para oviposição. Foram feitos experimentos com formigas e membracídeos secos montados em ramos pareados de S. vinosa, entre os quais a borboleta poderia escolher. Fêmeas de P. polibetes preferiram ovipositar em ramos contendo a pista visual de formigas + membracídeos ou apenas de formigas, não havendo preferência quando apenas membracídeos estavam presentes. O número de ovos foi maior apenas quando a pista visual de formigas + membracídeos estava presente. Isso revela a importância da visão para a escolha do local de oviposição por P. polibetes, embora não se descarte o uso de pistas químicas ou táteis. A imagem de formigas deve ser recorrente em muitas espécies de plantas hospedeiras utilizadas por P. polibetes, e fêmeas capazes de utilizá-la na hora da oviposição teriam vantagem dada a importância das formigas para a sobrevivência das larvas. As pistas utilizadas por borboletas com diferentes níveis de mirmecofilia para escolha do local de oviposição representam um campo de estudo pouco explorado, que poderá revelar novos aspectos sobre a interação entre lepidópteros e formigas / Abstract: Because the larvae have restricted mobility, the location chosen for oviposition and immature development may have a crucial effect on Lepidoptera fitness. Chemical, visual and/or tactile cues from the host plant are usually utilized during host plant selection, but the presence of natural enemies or mutualistic partners is also important. In the case of myrmecophilous species, oviposition can be mediated by the tending ants, but little is known about how the female perceive ants, and use them as cues. Parrhasius polibetes, a poliphagous lycaenid that presents facultative myrmecophily, is commonly found in Schefflera vinosa (Araliaceae), a bush commonly hosting aggregations of the treehopper Guayaquila xiphias. P. polibetes and G. xiphias can be tended by the same ants, and P. polibetes larvae have their survivorship increased when they occur close to associations of G. xiphias + ants. Female butterflies prefer to oviposit on branches where the association is present, even though the signal used in this choice is unknown. The objective of this study was to investigate whether P. polibetes visually recognize ant-treehopper associations and use them as clue for oviposition. Behavioral trials consisted of dried ants and treehoppers mounted on paired S. vinosa branches, between which the butterfly could choose. P. polibetes females preferred to oviposit on branches containing ants + treehoppers or only ants, and showed no preference when only treehoppers were present. The number of eggs was greater only when both ants and treehoppers were present on a branch. These results reveal the importance of vision during the oviposition process in P. polibetes, even though chemical and tactile clues may also be used. The image of ants is probably recurrent in many host plant species used by P. polibetes, and females capable of perceiving them during oviposition would have an advantage, given the importance of ants for larval survival in this species. So far, the cues used during egg-laying by butterflies with different levels of myrmecophily have not been explored in detail; and further investigations might reveal new aspects about the behavioral interface of butterfly-ant interactions / Mestrado / Ecologia / Mestra em Ecologia

Long-term studies are important for understanding the intricacies of population dynamics over time. Self-recruitment and social hierarchy are valuable tools to quantify the rates at which populations change. In mutualistic symbiosis, where two species benefit from the relationship, different selective pressures and life histories can have unintended consequences on the population dynamics of both species. Anemonefish live in a sized-based hierarchy where individuals queue to be part of the breeding pair (ranks 1 and 2). They have a mutualistic association with their host anemone; the identity of the anemone can impact their growth and fecundity. However, there is limited knowledge on the anemone lifespan and its site persistence over time. Here, we investigate rank changes and self-recruitment in Amphiprion percula and persistence in a common host anemone, Stichodactyla gigantea, on the remote island of Kimbe Island in Papua New Guinea. The populations of A. percula (n = 1,530) and their local host anemones, S. gigantea (n = 290) and Heteractis magnifica (n = 174), were sampled exhaustively in 2011 and 2019. Using DNA profiling, I determined the fate of individuals between years. We found that 21% of the A. percula population survived over the eight-year time gap compared to the 69% survival of the associated S. gigantea population in a six-year time gap. Half of the surviving A. percula individuals increased in rank and exhibited faster growth rates living on S. gigantea compared to H. magnifica. Self-recruitment was high in both years, 47% in 2011 and 39% in 2019, with one individual returning to its natal anemone. Our findings provide rare insights into one of the most charismatic symbiotic relationships in the marine environment such as the first documentation of longevity in a host anemone.

Algal blooms and the reduction of the seabed’s oxygen have a particularly negative impact on the Baltic Sea, caused by the eutrophication process. The process of eutrophication involves the gradual enrichment of a body of water, or portions of it, with minerals and nutrients, especially nitrogen and phosphorus. In Sweden, agriculture is the source of almost half of the nitrogen and phosphorus released into the environment. (Swedish Board of Agriculture 2013) As a result of eutrophication catalysed by climate change, marine biodiversity and fish stocks suffer also reducing the welfare of citizens. Around 30% of the total nitrogen inputs come from atmospheric sources, mostly combustion operations connected to shipping, road traffic, energy generation, and agriculture. (HELCOM 2017) Despite the fact that nutrient leakage has decreased in recent years, 97% of the surface of the Baltic Sea is still affected by eutrophication (HELCOM 2017). Taking this as an emergency call, research aims to investigate on how architecture can become a catalyst for environmental regeneration, resulting in a net positive outcome. The research refers to the theory of regenerative design, which has received particular attention in recent years in addressing constraints of sustainability. The design proposal aims to spatialize regenerative processes operating on different scales, from bio-material development to an urban masterplan. The research envisions a regenerative approach to the Baltic Sea by introducing a network of interventions operating on the transitional zone between agricultural fields and rivers transmitting nutrient pollution to the sea as part of its catchment basin. The design proposal integrates regenerative strategies learned from case studies and a literature review. Research speculates on how to reduce excessive nutrient enrichment in soil, water and decrease anthropogenic nutrient loading, while engaging with the local community through eco-recreation. Enlisting nature as a guide and referring to biomimicry as the model, the network of various functional zones suggests bioremediation of polluted agricultural fields. At the same time proposal providide alternative platforms for cultivation and recreational infrastructures closely related to an adjusted urban fabric applied in the territory of Umeå in Sweden.