One of the main challenges in the study of insect communities is to explain what determines species diversity and how it occurs. Many ecological factors have been reported to affect the richness and composition of species in biological communities and different ecological and environmental factors can structure ant communities on different spatial scales (Kaspari & Weiser 1999; Kneitel & Chase 2004). In the wetlands of the Pantanal, Mato Grosso do Sul, Brazil, dry and rainy seasons alternate annually. During the rainy season, a large plain, which includes parts of Paraguay, Bolivia, and Brazil, is covered by the flood (Feener et al. 2008). Floods are the main regulating force of diversity patterns and processes in the area (Adis et al. 2001). Faunal diversity depends on the seasonality of important structural events, which usually leads to the inundation of large areas (Raizer & Amaral 2001). The Pantanal is one of the least known biomes of Brazil, and it has been suggested that the functional role of invertebrates in this ecosystem has a large contribution to its preservation (Lewinsohn et al. 2005). The ant family Formicidae is one of the most successful insect groups, and includes one of the highest species number and biomass among invertebrates, being also omnipresent in a wide range of environments (Santos et al. 2003; Battirola et al. 2005), easy to collect and identify, and responding relatively quickly to habitat changes (Ribas & Shoereder 2007). In addition, a significant correlation between habitat structural characteristics and structural patterns of ant communities has often been found (Samways 1983; Soares et al. 2007). Although some previous studies have demonstrated that the coexistence of arboreal ant species is affected by various abiotic and biotic factors (

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Understanding the mechanisms that determine local patterns of diversity is among the primary goals of ecology. Among these mechanisms, competition is mentioned as the regulatory factor structuring biological communities, despite the fact that the concept is controversial in ecology. Myrmecologists, however, for the most part, view competition as one of the main factors structuring ant communities. Two hypotheses on the mechanisms underlining species coexistence have received support from empirical studies. The first predicts a balance between competition and colonization, which form a continuum along which species are distributed. Species at one extreme are good at competing and bad at colonizing, whereas species on the opposite end are bad competitors and good colonizers. The interactions among various species over time are in a state of constant flux along this continuum. The second hypothesis predicts spatial clustering. According to it, ecologically dominant species have an aggregated spatial distribution, which would increase competition among individuals and the species' coexistence with subordinate species. Beyond these two, there are the trade-off and the mosaic theories, which involve competition and promote coexistence, and also the null models, which are used to determine if competition is responsible for ant community structures. In the Myrmecology, the competition is par excellence as one of the main factors structuring ant communities. Some hypotheses have been supported in empirical studies of natural communities as mechanisms for species coexistence. The first is the balance competition/colonization, species were distributed along a continuum between good and bad contestants competing colonizing up bad and good colonizers, and their interactions over time would allow a state of constant flux along this continuum. The second hypothesis is the spatial clustering, in which ecologically dominant species have an aggregated spatial distribution, which would increase competition among individuals and species coexistence with subordinates. Besides these there are the trade-off theory and the mosaics, which involve competition and promote coexistence, and also the null models, which are used to determine if competition structures communities of ants. However, the objective is to demonstrate the main mechanisms that involve competition in structuring ant communities

Este estudo teve como objetivo a realização de um diagnóstico do processo de ensino e de aprendizagem, tendo como eixo norteador o tema Agrotóxico. A partir desta temática, foram propostas aulas que abordaram conteúdos elencados nos componentes curriculares de história, geografia, biologia, química e língua portuguesa, visando oferecer aos estudantes e professores sugestões de aulas interdisciplinares. Inicialmente, foi realizado um diagnóstico dos conhecimentos prévios que os estudantes têm sobre os agrotóxicos. As demais etapas do projeto foram estruturadas após a análise desses conhecimentos de estudantes do ensino médio em uma escola localizada no distrito de Ipezal, munícipio de Angélica, Mato Grosso do Sul (MS). A referida escola é considerada do campo e possui o eixo temático Terra, Vida e Trabalho (TVT), porém nunca abordou o tema Agrotóxico no âmbito da pesquisa acadêmica entre a comunidade interna. Ademais, os estudantes convivem com o agronegócio intenso na região, uma vez que o município concentra lavouras ao redor e também seis usinas de álcool e açúcar em seu entorno. Por conta de tais fatores, foi realizado o diagnóstico para que, posteriormente, pudessem ser oferecidas sugestões de aplicação de metodologias didáticas que viessem a atender os interesses e os conhecimentos prévios dos estudantes. O trabalho alcançou pontos positivos, principalmente no que se refere aos danos causados por agrotóxicos na população, pois de acordo com as respostas dos estudantes, todos podem ser prejudicados quanto à saúde.