17 research outputs found

    Which Factors Determine Spatial Segregation in the South American Opossums (Didelphis aurita and D. albiventris)? An Ecological Niche Modelling and Geometric Morphometrics Approach

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    Didelphis albiventris and D. aurita are Neotropical marsupials that share a unique evolutionary history and both are largely distributed throughout South America, being primarily allopatric throughout their ranges. In the Araucaria moist forest of Southern Brazil these species are sympatric and they might potentially compete having similar ecology. For this reason, they are ideal biological models to address questions about ecological character displacement and how closely related species might share their geographic space. Little is known about how two morphologically similar species of marsupials may affect each other through competition, if by competitive exclusion and competitive release. We combined ecological niche modeling and geometric morphometrics to explore the possible effects of competition on their distributional ranges and skull morphology. Ecological niche modeling was used to predict their potential distribution and this method enabled us to identify a case of biotic exclusion where the habit generalist D. albiventris is excluded by the presence of the specialist D. aurita. The morphometric analyses show that a degree of shape discrimination occurs between the species, strengthened by allometric differences, which possibly allowed them to occupy marginally different feeding niches supplemented by behavioral shift in contact areas. Overlap in skull morphology is shown between sympatric and allopatric specimens and a significant, but weak, shift in shape occurs only in D. aurita in sympatric areas. This could be a residual evidence of a higher past competition between both species, when contact zones were possibly larger than today. Therefore, the specialist D. aurita acts a biotic barrier to D. albiventris when niche diversity is not available for coexistence. On the other hand, when there is niche diversification (e.g. habitat mosaic), both species are capable to coexist with a minimal competitive effect on the morphology of D. aurita

    Habitar a metrĂłpole: os apartamentos quitinetes de Adolf Franz Heep

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    The restructuring of the housing market and the emergence of a new housing typology in Sao Paulo from the mid-1940s, the kitchenette apartment, coincided with changes in the parameters that guided disciplinary discourse and architectural practice in Brazil. Analyze the moment the new typology was formulated, their initial motivations and subsequent developments, allows not only to recover the trajectory of the German architect Adolf Franz Heep (1902-1978) as investigate the dialogue between European architectural avant-garde, the North-American experiences, the local architectural production and the local demands

    Pervasive gaps in Amazonian ecological research

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    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    A História da Alimentação: balizas historiogråficas

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    Os M. pretenderam traçar um quadro da HistĂłria da Alimentação, nĂŁo como um novo ramo epistemolĂłgico da disciplina, mas como um campo em desenvolvimento de prĂĄticas e atividades especializadas, incluindo pesquisa, formação, publicaçÔes, associaçÔes, encontros acadĂȘmicos, etc. Um breve relato das condiçÔes em que tal campo se assentou faz-se preceder de um panorama dos estudos de alimentação e temas correia tos, em geral, segundo cinco abardagens Ia biolĂłgica, a econĂŽmica, a social, a cultural e a filosĂłfica!, assim como da identificação das contribuiçÔes mais relevantes da Antropologia, Arqueologia, Sociologia e Geografia. A fim de comentar a multiforme e volumosa bibliografia histĂłrica, foi ela organizada segundo critĂ©rios morfolĂłgicos. A seguir, alguns tĂłpicos importantes mereceram tratamento Ă  parte: a fome, o alimento e o domĂ­nio religioso, as descobertas europĂ©ias e a difusĂŁo mundial de alimentos, gosto e gastronomia. O artigo se encerra com um rĂĄpido balanço crĂ­tico da historiografia brasileira sobre o tema

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

    Imagens em trùnsito: as virgens de Lujån e Sumampa e os circuitos coloniais na América Meridional na primeira metade do século XVII

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    This article seeks to analyze the materiality and part of the trajectory of two seventeenth-century terracotta statuettes - one of Nossa Senhora da Conceição and another of Nossa Senhora da Consolação - who respectively became the Virgin of LujĂĄn, patron of Argentina, and Virgen of Sumampa. Both are understood here as intertwined in the various networks and connections between the Portuguese and Spanish America in the contiguous areas of South America in the first half of the seventeenth century. In the text, we discuss a possible "Paulista" origin of these images which, in addition to an apparent coincidence, attests that the great "Peruvian space," articulated by PotosĂ­, also included distinct regions of Portuguese America. Ii is in this expanded space marked by the traffic of people, goods and objects linked to the networks of smuggling that we follow the paths of these two images, trying to visualize how they got peculiar meanings in different contexts and environments.Neste artigo busca-se analisar a materialidade e parte da trajetĂłria de duas imagens seiscentistas em terracota - uma de Nossa Senhora da Conceição e outra de Nossa Senhora da Consolação - que se tornaram, respectivamente, a Virgen de LujĂĄn, padroeira da Argentina, e a Virgen de Sumampa. Ambas sĂŁo compreendidas aqui como entrelaçadas nas variadas redes e conexĂ”es estabelecidas entre a AmĂ©rica portuguesa e espanhola, nos espaços contĂ­guos da AmĂ©rica Meridional na primeira metade do sĂ©culo XVII. No texto, discute-se uma possĂ­vel procedĂȘncia "paulista" dessas imagens, o que, para alĂ©m de uma aparente casualidade, atesta como o grande "espaço peruano", articulado por PotosĂ­, incluĂ­a tambĂ©m distintas regiĂ”es da AmĂ©rica portuguesa. É nesse espaço ampliado, marcado pelo trĂĄfego de pessoas, mercadorias e objetos atrelados Ă s redes comerciais de contrabando, que acompanhamos os percursos dessas duas imagens, buscando visualizar como elas ganharam sentidos peculiares em ambientes e contextos diversos
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