Orientador: Nilza Maria Martinelli / Coorientador: Márcio da Silva Araújo / Banca: Francisco Jorge Cividanes / Banca: Nelson Wanderley Perioto / Banca: Edison Ryoiti Sujii / Banca: Douglas Henrique Bottura Maccagnan / Resumo: O objetivo deste estudo foi conhecer a composição de espécies de formigas epigéicas, nas diferentes estações climáticas do ano; do estrato arbustivo-arbóreo, bem como avaliar se existe correlação entre porte das plantas e riqueza de espécies de formigas e comparar a mirmecofauna em três estratos verticais (solo, arbustivo e arbóreo), em duas fitofisionomias de Cerrado goiano, no município de Ipameri, GO. Para a realização das coletas, em cada fitofisionomia, foram selecionados 30 pontos de amostragens no solo e 30 plantas entre arbustos e árvores distribuídos ao longo de um transecto medindo cerca de 100 m de comprimento. Em cada ponto foi colocada uma armadilha do tipo pitfall, enterrada ao nível do solo, contendo álcool 50% e em cada planta foram colocados dois tipos de iscas, que consistiram de um copo plástico com capacidade de 110 mL, contendo sardinha e a outra contendo mel. Foram realizadas duas coletas por mês, durante um ano, no período de julho/2011 a junho/2012. Quanto á composição de formigas epigéicas, foram coletadas 51 espécies de formigas na fitofisionomia Cerradão, distribuídas em sete subfamílias e, 48 espécies em Cerrado sentido restrito, distribuídas em seis subfamílias. Houve diferença significativa nas constâncias entre as espécies de formigas, entre as estações do ano e para a interação constância das espécies versus estação do ano, em ambas as fitofisionomias. Por meio de curvas de acumulação de espécies, observou-se que o esforço amostral realizado foi satisfatório nos dois ambientes. A riqueza média de espécies estimada não indicou diferença significativa entre as estações. Com relação á composição de espécies do estrato arbustivo-arbóreo, foram coletadas 40 espécies de formigas, distribuídas em 13 gêneros e seis subfamílias em Cerradão e destas, 23 foram consideradas acidentais (z), 10 constantes (w) e sete acessórias (y). Em Cerrado sentido ... / Abstract: The aim of this study was to determine the species composition of ants epigaeic, in different seasons of the year; the woody layer, and assess whether there ia a correlation between plant height and species richness of ants and ant fauna compare the three strata vertical (soil, shrubs and trees) in two Cerrado goiano physiognomies, in the municipality of Ipameri, GO. To carry out the collections in each vegetation type, 30 sampling sites and 30 plants in the soil between shrubs and trees distributed along a transect measuring about 100 m in length were selected. At each point a trap was placed pitfall of the type buried ground level, containing 50% alcohol in each plant, and two types of lures, which consisted of a plastic cup with a capacity of 110 ml, containing honey and the other containing sardines were placed. Two samples per month were held for one year, between June/2012 July/2011 to. As to the composition epigaeic ants, were collected 51 species of ants distributed in seven subfamilies in Cerradão and 48 species distributed in six subfamilies in Cerrado sensu stricto. There were significant differences between species in the constancy of ants, between the seasons and the interaction of species constancy versus season in both phytophysiognomies. Through species accumulation curves, it was observed that the sampling effort was achieved in both environments. The species richness values estimated indicated no significant difference between the seasons. With respect to the composition of species of woody layer, were collected 40 ant species, distributed in 13 genera and six subfamilies in Cerradão. Of the 40 species collected, 23 were accidental (z), 10 constants (w) and seven accessory (y). In Cerrado sensu stricto, 36 ant species, distributed in 12 genera and six subfamilies were collected. This phytophysiognomy a larger number of accidental species was also detected (18), followed by 11 species constants and seven accessory ... / Doutor

Ants are fascinating creatures - not so much because they are intelligent on their own, but because as a group they display compelling emergent behaviour (the extent to which one observes features in a swarm which cannot be traced back to the actions of swarm members). What does each swarm member do which allows deliberate engineering of emergent behaviour? We investigate the development of a language for programming swarms of ant agents towards desired emergent behaviour. Five aspects of stigmergic (pheromone sensitive computational devices in which a non-symbolic form of communication that is indirectly mediated via the environment arises) and message passing ant agents (computational devices which rely on implicit communication spaces in which direction vectors are shared one-on-one) are studied. First, we investigate the primitive behaviours which characterize ant agents' discrete actions at individual levels. Ten such primitive behaviours are identified as candidate building blocks of the ant agent language sought. We then study mechanisms in which primitive behaviours are put together into XSets (collection of primitive behaviours, parameter values, and meta information which spells out how and when primitive behaviours are used). Various permutations of XSets are possible which define the search space for best performer XSets for particular tasks. Genetic programming principles are proposed as a search strategy for best performer XSets that would allow particular emergent behaviour to occur. XSets in the search space are evolved over various genetic generations and tested for abilities to allow path finding (as proof of concept). XSets are ranked according to the indices of merit (fitness measures which indicate how well XSets allow particular emergent behaviour to occur) they achieve. Best performer XSets for the path finding task are identifed and reported. We validate the results yield when best performer XSets are used with regard to normality, correlation, similarities in variation, and similarities between mean performances over time. Commonly, the simulation results yield pass most statistical tests. The last aspect we study is the application of best performer XSets to different problem tasks. Five experiments are administered in this regard. The first experiment assesses XSets' abilities to allow multiple targets location (ant agents' abilities to locate continuous regions of targets), and found out that best performer XSets are problem independent. However both categories of XSets are sensitive to changes in agent density. We test the influences of individual primitive behaviours and the effects of the sequences of primitive behaviours to the indices of merit of XSets and found out that most primitive behaviours are indispensable, especially when specific sequences are prescribed. The effects of pheromone dissipation to the indices of merit of stigmergic XSets are also scrutinized. Precisely, dissipation is not causal. Rather, it enhances convergence. Overall, this work successfully identify the discrete primitive behaviours of stigmergic and message passing ant-like devices. It successfully put these primitive behaviours together into XSets which characterize a language for programming ant-like devices towards desired emergent behaviour. This XSets approach is a new ant language representation with which a wider domain of emergent tasks can be resolved.

Orientador: Fernando Carlos Pagnocca / Banca: José Eduardo Marcondes de Almeida / Banca: Odair Correa Bueno / Resumo: Os gêneros de formigas-cortadeiras, Atta e Acromyrmex, mantém uma associação mutualística com o basidiomiceto Leucoagaricus gongylophorus, o qual é responsável pela produção de enzimas que degradam o material vegetal transportado para o interior dos ninhos. As formigas-cortadeiras são consideradas pragas devido a enorme quantidade de material vegetal que é cortada, principalmente em ambientes alterados por atividades antrópicas, como os locais de agricultura e reflorestamento. Devido à necessidade de manejo das formigascortadeiras, o controle biológico representa um método promissor e ambientalmente amigável. Nesse contexto, devido a íntima relação entre as formigas e o fungo mutualista, é de grande importância selecionar linhagens de fungos filamentosos que possam interferir negativamente sobre o jardim de fungos. No presente trabalho isolamos fungos filamentosos contaminantes de colônias iniciais da formiga Atta sexdens rubropilosa. Após o isolamento e identificação foram realizados testes para avaliar o crescimento desses fungos utilizando o jardim de fungos como substrato, e também as linhagens consideradas melhores nesse aspecto foram testadas em colônias completas. A combinação de dois fungos (Trichoderma harzianum e Trichoderma virens) mostrou-se promissora para prosseguimento nos testes e futuro uso no controle biológico. Adicionalmente, foi avaliada e secreção de compostos orgânicos voláteis através de análises GC/MS de três linhagens de fungos filamentosos após sete dias de crescimento em culturas individuais e também frente ao fungo mutualista. Ainda, utilizando a microscopia eletrônica de varredura, avaliamos como ocorre a interação do fungo R. variabilis frente ao fungo mutualista, demonstrando que o fungo R. variabilis possui caráter micoparasita ao interagir com o fungo mutualista / Abstract: The leaf-cutting ants, Atta and Acromyrmex, maintain a mutualistic association with the basidiomycete Leucoagaricus gongylophorus, which is responsible for the production of enzymes that degrade the plant material transported to the interior of the nests. The leafcutting ants are considered pests due to an enormous amount of plant material they cut, mainly at areas altered by anthropic activities, such as agricultural and reforestation sites. Due to the need for management of the leaf cutting ants, biological control represents a promising and environmentally friendly method. In this context, due to the close relationship between ants and mutual fungi, it is of great importance to select strains of filamentous fungi that negatively impact the fungus garden. Thus, in the present study, we evaluated lineages of filamentous fungi isolated from the initial colonies of Atta sexdens rubropilosa. After isolation and identification of the contaminants filamentous fungi, assays were carried out in order to determine the fungal growth of the most suitable lineages on the fungus garden of the lab colonies The combination of two fungi (Trichoderma harzianum and Trichoderma virens) was promising for the development of methods aiming at the biological control of leaf-cutting ants. Additionally, the production of volatile organic compounds was evaluated by the GC / MS analysis of three of the filamentous fungal strains after 7 days of growth in individual cultures, and also in the presence of the mutualistic fungus. Images of scanning electron microscopy were taken during the co-culture assays / Mestre

Made available in DSpace on 2015-03-26T13:30:25Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1105450 bytes, checksum: 163c50636e0eaab0ec624fc7342a1a43 (MD5) Previous issue date: 2009-07-23 / Fundação de Amparo a Pesquisa do Estado de Minas Gerais / The Brazilian coast presents approximately 9,200 kilometers, which 5.000 km of them are occupied by the Restinga ecosystems. This ecosystem is a set of vegetation formations that develop in sandy plains dating from the Quaternary, within the Atlantic Forest domain. The plant species that occur in Restinga have high plasticity, presenting adaptations for their development under the influence of various biotic and abiotic factors such as drought stress, wind, topography and salinity. These factors influence the occurrence and distribution of plant communities in the Restinga, and similarly, should influence the distribution and diversity of animals. The aim of this dissertation was to test the assumption that the species richness of ants increases with distance from the ocean, as well as the following hypotheses: (1) ant species richness increases with plant species richness, which in turn increases with distance from the sea, (2) ant species richness is proportional to soil cover by plants and litter; (3) ant species richness increases with soil organic matter concentration, (4) ant species richness decreases with soil salinity, and (5) the species richness of ants responds positively to spatial heterogeneity of the environment. Moreover, we tested a second assumption that the distinct Restinga phytophysiognomies have different ant species composition. The ants were sampled in herbaceous and shrubby Restinga of the Morro dos Conventos in Araranguá (SC) using pitfall traps. Sixty-five pitfall traps were placed 10 meters away from each other in transects disposed from the ocean to the continent. At each sampling point, were collected the following explanatory variables: plant species richness, percentage of vegetation cover and litter, concentration of organic matter and salt in soil. In total, we collected 71 species of ants. Our results have confirmed both assumptions. Ant species richness was related to distance from the sea, plant species richness, soil cover by plant and litter. Moreover, we observed that different vegetation types within Restinga have specific communities of ants, where habitats near or with similar environmental conditions had higher similarity among them. These results indicate that the vegetation and environmental factors affected by them are the main factors determining the ant species richness and composition in Restinga. / O litoral brasileiro apresenta aproximadamente 9.200 quilômetros de extensão, das quais 5.000 km são ocupados por ecossistema de Restinga. Este ecossistema é um conjunto de formações vegetacionais que se desenvolvem em dunas e cordões arenosos do período Quaternário dentro do domínio da Floresta Atlântica. As espécies de plantas que ocorrem em Restinga possuem elevada plasticidade, apresentando adaptações para seu desenvolvimento sob influência de vários fatores abióticos como: estresse hídrico, ventos, topografia e salinidade. Tais fatores condicionam a ocorrência e a distribuição das comunidades vegetais em ambientes de Restinga, e similarmente, devem influenciar a distribuição e a diversidade da fauna animal. O presente estudo teve por objetivo testar o pressuposto de que a riqueza de espécies de formigas aumenta com o aumento da distância em que se encontram em relação ao oceano e as seguintes hipóteses explicativas: (1) a riqueza de espécies de formigas aumenta com a riqueza de espécies de plantas, que por sua vez aumenta com a distância do mar; (2) a riqueza de espécies de formigas é diretamente proporcional a cobertura do solo por plantas e serapilheira; (3) a riqueza de espécies de formigas aumenta com a concentração de matéria orgânica no solo; (4) a riqueza de espécies de formigas diminui com o aumento da concentração de sal no solo; e (5) a riqueza de espécies de formigas responde positivamente à heterogeneidade espacial do ambiente. Além disso, nós testamos um segundo pressuposto de que diferentes fitofisionomias de Restinga possuem composição de espécies de formigas específicas. As coletas de formigas foram realizadas na Restinga herbáceo-arbustiva do Morro dos Conventos, em Araranguá (SC) utilizando armadilhas de solo. Foram instaladas 65 armadilhas distantes 10 metros entre si, em dois transectos do oceano para o continente. Em cada ponto amostral, foram coletadas as seguintes variáveis explicativas: riqueza de espécies de plantas, percentagem de cobertura vegetal e de serapilheira, concentração de matéria orgânica e sal no solo. No total, foram coletadas 71 espécies de formigas. Os resultados obtidos permitiram confirmar nossos dois pressupostos. Observamos que a riqueza de espécies de formigas está positivamente relacionada com a distância em que se encontram do mar, com a riqueza de espécies de plantas, cobertura vegetal e cobertura por serapilheira do solo. Além disso, observamos que diferentes fitofisionomias dentro da Restinga apresentam comunidades de formigas específicas, e que em geral, habitats próximos ou com condições ambientais semelhantes apresentaram maior similaridade quanto à composição de espécies. Esses resultados sugerem que a vegetação e os fatores ambientais condicionados por ela, podem ser os principais fatores determinando a riqueza e composição de espécies de formigas em Restinga.

In this thesis we study a mathematical model that describes task partitioning in a colony of ants. This process of self-organization is modeled by a nonlinear coupled system of rst order autonomous ordinary dierential equations. We discuss how this system of equations can be derived based on the behavior of ants in a colony. We use GNU Octave (a high-level programming language) to solve the system of equations numerically for dierent sets of parameters and show how the solutions respond to changes in the parameter values. Finally, we prove that the model is well-posed locally in time. We rewrite the system of ordinary dierential equations in terms of a system of coupled Volterra integral equations and look at the right-hand side of the system as a nonlinear operator on a Banach space. By doing so, we have transformed the problem of showing existence and uniqueness of solutions to a system of ordinary dierential equations into a problem of showing existence and uniqueness of a xed point to the corresponding integral operator. Additionally, we use Gronwall's inequality to prove the stability of solutions with respect to data and parameters.

Made available in DSpace on 2014-06-11T19:35:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2002-04Bitstream added on 2014-06-13T20:45:45Z : No. of bitstreams: 1 rando_jss_dr_botfca.pdf: 3081622 bytes, checksum: ace02e72737d4f6ac3d78fb6c3f7e0fa (MD5) / Este trabalho é o resultado de coletas realizadas pelo profo Dr. Luiz Carlos Forti nos anos de 1993 e 1994 em vários municípios dos Estados de Santa Catarina, Paraná, São Paulo, Mato Grosso do Sul, Minas Gerais, Goiás, Mato Grosso, Rondônia, Acre, Amapá, Amazonas e também Guiana Francesa e Paraguai, com o objetivo de atualizar a distribuição geográfica das formigas cortadeiras de folhas dos gêneros Atta Fabricius, 1804 e Acromyrmex Mayr, 1865. Nos diversos municípios foram feitos transectos localizados ao acaso e, sempre que possível, coletou-se dados sobre densidade de colônias, tipos de vegetação e exemplares de formigas dos dois gêneros para posterior exame no laboratório de Insetos Sociais-Praga da FCA/UNESP, Botucatu-SP. Além dos dados relativos aos 11 Estados do Brasil, incluiu-se o resultado das identificações de exemplares recebidos de diversos locais e datas para o referido laboratório. Concluiu-se que A. laevigata e A. capiguara foram as espécies encontradas em maior número de municípios amostrados do Brasil. A. sexdens piriventris somente foi encontrada na região sul do Brasil, com grande predomínio nos Estados de Santa Catarina e Rio Grande do Sul. A região Sudeste se caracterizou pela ocorrência de A. capiguara e A. laevigata, nesta ordem, sendo que em Minas Gerais, a espécie de maior ocorrência foi A. laevigata. A. capiguara também se destacou no Estado do Paraná. A. capiguara predominou em áreas cobertas por gramíneas e A. laevigata não apresentou preferência destacada quanto a cobertura vegetal. A. laevigata ocorreu de forma generalizada nas regiões Centro-Oeste e Norte do Brasil. A. sexdens rubropilosa esteve presente em todas as regiões do Brasil, com predominância nos Estados do Paraná e Minas Gerais..... / This work is the result of collects, done by professor Luiz Carlos Forti between years 1993 and 1994, in many cities on States of Santa Catarina, Paraná, São Paulo, Mato Grosso do Sul, Minas Gerais, Goiás, Mato Grosso, Rondônia, Acre, Amapá, Amazonas in Brazil and also Guiana Francesa and Paraguay, with the purpose to obtain an up-to-date geographical distribution of leaf cutting ants from genus Atta Fabricius, 1804 and Acromyrmex Mayr, 1865. Among cities it were done, on randomized areas, when it was possible, data collections as: colony densities, kind of vegetation and ants specimens from both genus for later laboratory tests at Insetos Sociais-Praga da FCA/UNESP, Botucatu-São Paulo State. Beyond data, related to eleven states of Brazil, it were include yet, in this work, results of specimens identification from different places and dates, received for identifications to mentioned laboratory. It was conclude that A. laevigata Smith, 1858 e A. capiguara Gonçalves, 1944 were species found on higher number of randomized cities in Brasil. A. sexdens piriventris Santschi, 1919 was found only at South region in Brazil, in States of Santa Catarina and Rio Grande do Sul. In Southwest region were found A. capiguara and A. laevigata, by this order but, in Minas Gerais State, higher frequency was of A. laevigata. A. capiguara had detached in Paraná State too, higher on areas of grassland. A. laevigata had no detached preference of vegetal covering and occurred, as general way, at regions of Middle-West and North of Brazil. A. sexdens rubropilosa Forel, 1908 was found at all regions of Brasil, with supremacy at States of Paraná and Minas Gerais. It were observed at first time occurrences of A. laevigata in States of Amapá and Rio Grande do Sul. It was registered, at first time too, occurrence of A. opaciceps Borgmeier, 1939 in State of Alagoas...(Complete abstract, click electronic address below).

Made available in DSpace on 2015-04-09T12:28:14Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-06-16Bitstream added on 2015-04-09T12:47:55Z : No. of bitstreams: 1 000812481.pdf: 3478089 bytes, checksum: 5f47c3b03ce4abf5fc80a8887c11eccf (MD5) / As formigas ocupam dosséis de árvores e arbustos, com muitas espécies utilizando a interface solo/serapilheira para forrageamento e outras com hábito residente nos solos. Nesse trabalho se propôs identificar espécies de formigas em um domínio de Cerrado à Nordeste do Estado do Maranhão e correlacionar a ocorrência das formigas com atributos dos solos, da vegetação, da umidade e temperatura ao nível do solo. O trabalho foi realizado no município de Chapadinha – MA em seis ambientes: A1 e A2 LATOSSOLO AMARELO Distrófico típico, A3 NEOSSOLO FLÚVICO Distrófico típico, A4 LATOSSOLO AMARELO Distrófico petroplíntico, A5 ARGISSOLO ACINZENTADO Distrófico arênico e A6 PLINTOSSOLO PÉTRICO Litoplíntico êndico. A caracterização da cobertura vegetal foi realizada a partir levantamento fitossociológico em parcelas de 40 x 40 m. Nessas parcelas foram coletadas amostras de solo deformadas e com estrutura preservada nas camadas 0,0 – 0,1 m, 0,1 – 0,2 m e 0,2 – 0,3 m para caracterização física e química. As formigas foram coletadas em cada ambiente com auxílio de iscas proteicas e carboidráticas (sardinha e mel). Nove conjuntos de iscas foram distribuídas em uma malha amostral quadrada (40 x 40 m) e a distância entre as iscas foi de dez metros uma da outra. Cada isca foi monitorada individualmente, por um período de 1 hora, entre 08:00 às 11:00 horas. As formigas que acessaram as iscas foram acompanhadas e coletadas diretamente na entrada dos respectivos formigueiros. A biomassa seca de serapilheira foi obtida em parcelas de 1 m2 distribuídas aleatoriamente nas parcelas de 40 x 40 m. As medidas de umidade e temperatura foram obtidas com auxílio de termohigrômetro posicionado diretamente na superfície do solo dos ambientes de amostragem. Os atributos físicos e químicos do solo receberam tratamento estatístico descritivo e foram usados nas correlações multivariadas, utilizando análise de componentes ... / Ants live in tree tops and shrubs, with many species using the soil/litter interface for foraging and other are resident in the soils. In this study proposes to identify species of ants in an area of the Cerrado Northeastern State of Maranhao and correlate the occurrence of ants with attributes of soils, vegetation, moisture and temperature at ground level. The study was conducted in the municipality of Chapadinha-MA in six environments: E1 and E2 Typical Dystrophic Oxisol, E3 Entisol Typical Dystrophic, E4 Petroplíntico Dystrophic Oxisol, E5 Paludalf Dystrophic Ultisol and E6 Plinthosol Petrico Êndico Litoplíntico. The characterization of the vegetation was carried out by phytosociological survey in 40 x 40 m plots. To evaluate the physical and chemical properties of the soils we collected disturbed soil samples and preserved structure in 0,0 - 0,1 m, 0,1 - 0,2 m and 0,2 - 0.3 m layers. The ants were collected with protein and a carbohydrate baits (sardines and honey) using nine pairs of baits distributed in the 40 x 40 m plots from six environments. To collect the ants in each plot the baits were observed individually for one hour (08:00 and 11:00 am) and the ants who accessed the baits were monitored and collected directly at the entrance of their nests. The dry biomass of litter was obtained in 1 m2 plots randomly distributed in 40 x 40 m plots. Humidity and temperature were obtained with hygrometer placed directly on the soil surface from the sampling environments. Descriptive statistical analysis and Principal Component Analysis (PCA) was carried out in the physical and chemical soil attributes. Ten ant species with higher importance value (HIV) were used in the PCA analysis. These species were correlated with soil attributes, litter biomass, basal area, humidity and temperature at ground level. Forty eight species from 7 subfamilies and 24 genera have been found. Nine species were restricted to records environments: E1 and ...

Made available in DSpace on 2014-11-10T11:09:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-09-03Bitstream added on 2014-11-10T11:58:44Z : No. of bitstreams: 1 000729311.pdf: 1030989 bytes, checksum: eaab2165bdf2127142b441d6bab8557d (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / As formigas da tribo Attini são conhecidas pelo hábito de cultivar fungos mutualistas (Basidiomycota) em uma variedade de materiais coletados para formar o que é chamado de jardim de fungo. Este hábito teve início há cerca de 50 milhões de anos na América do Sul e deu origem a cinco tipos de agricultura, que diferem no tipo de fungo e material coletado. As attíneas utilizam os jardins de fungos como fonte de nutrientes e enzimas, os quais são produzidos não somente pelo fungo mutualista, mas também por outros microrganismos presentes no ninho. Portanto, para as formigas e fungos terem acesso a nutrientes são necessárias associações com outros microrganismos. Estudos das comunidades microbianas associadas às formigas Attini, na maioria das vezes, estão relacionados aos jardins de fungo e objetivam explorar os mecanismos de degradação da biomassa vegetal. Informações sobre a microbiota associada ao corpo das formigas e sua função ainda são insuficientes. As attíneas dependem dos simbiontes para sua nutrição e proteção contra parasitas. Mas alguns desses microrganismos são ameaças às formigas e outros parecem ser apenas comensais. No presente trabalho, as bactérias associadas às formigas Attini Atta laevigata, Trachymyrmex urichi eMycocepurus goeldii foram identificadas por métodos independentes de cultivo e um cenário no qual a evolução das formigas Attini é moldada pela interação com estes microrganismos foi proposto. Além disso, foi desenvolvido um protocolo de lavagem das formigas para eliminar bactérias externas e ser utilizado para amostrar os microrganismos do interior das formigas. Os resultados mostraram diferenças entre as comunidades bacterianas abrigadas pelas formigas Attini estudadas. A discriminação de bactérias internas e externas ao corpo das formigas foi possível devido à padronização e aplicação do protocolo de lavagem desenvolvido. Foi descoberto que nos intestinos da Attini mais basal M. goeldii predomina uma única espécie de Spiroplasma. No entanto, durante a evolução, esta bactéria foi progressivamente substituída por duas espécies de Rhizobiales no intestino da attínea filogeneticamente intermediária T. urichi, e finalmente uma única espécie de Rhizobiales prevaleceu como a espécie bacteriana única nos intestinos da formiga cortadeira mais derivada A. laevigata. As cortadeiras também carregam em suas cutículas, quantidades consideráveis de Acetobacter. Rhizobiales e Acetobacter pertencem a grupos de bactérias fixadoras de nitrogênio. Assim, é concebível que a especialização em mutualistas fixadores de nitrogênio possa ter desempenhado um papel no aumento do tamanho da população e do tamanho do corpo ao longo da evolução das formigas Attini. O aumento da população pode estar associado com o aumento nas taxas de infecção, mas esta tendência foi aparentemente compensada pela alta complexidade social das cortadeiras e pela manutenção de espécies de Burkholderiales e Actinomycetales, encontradas na sua cutícula. Estas bactérias produtoras de antibióticos podem ter assumido o papel protetor que está atribuído a Pseudonocardiaceae nas demais espécies de Attini. Também foi detectada uma associação com espécies de Wolbachia que parecem ser mutualistas e externas ao corpo das attíneas, provavelmente nas cutículas. Esta associação pode ter iniciado na Attini mais basal, se especializado na intermediária, mas foi perdida na mais derivada. As associações mutualistas parecem ser recentes e ter se originado a partir de uma única aquisição das fixadoras de nitrogênio e múltiplas aquisições de bactérias que produzem antibióticos. / Ants of the Attini tribe are known for the habit of cultivating mutualistic fungi (Basidiomycota) on a variety of harvested materials to form what is called the fungus garden. This habit originated approximately 50 million years ago in South America and gave rise to five agricultural systems, which differ in the type of fungus and collected material. Attine ants utilize the fungus garden as a source of nutrients and enzymes, which are not only produced by the mutualistic fungus, but also by other microbes present in the garden. Therefore, for ants and fungi have access to these nutrients associations with other microorganisms became necessary. Studies of microbial community associated with attine ants are mostly related to the fungus gardens and aim to explore the mechanisms of plant biomass degradation. Information on the microbiota associated with the body of ants and its function are still lacking. Attine ants rely on microbial symbionts for nutrition and protection against parasites. On the other hand, some microbes threatens these ants and others appear to be only commensals. In this work, the bacteria associated with the attine ants Atta laevigata, Trachymyrmex urichi and Mycocepurus goeldii were identified by culture-independent methods and a scenario in which the evolution of attine ants is shaped by the interaction with these microorganisms has been proposed. In the present study a washing protocol was also developed to remove external bacteria, and used to sample microorganisms living inside the ants and possibly other insects. The results showed differences between the bacterial communities harbored by the attine ants studied. Discrimination of internal and external ants’ body bacteria was possible due to the standardization and application of the developed washing protocol. It was observed that the intestines of most basal attine M. goeldii are dominated by a single species of Spiroplasma. However, during the attine ants’ evolution, this bacterium was progressively replaced by two Rhizobiales species in the gut of the phylogenetically intermediate T. urichi, and finally a single species of Rhizobiales prevailed as the unique bacterial species in the gut of the most derived leaf-cutter ant A. laevigata. Leaf-cutters also harbor on their cuticles considerable amounts of Acetobacter sp. Both Rhizobiales and Acetobactersp. species are in the group of nitrogen-fixing bacteria. Thus, it is conceivable that specialization in nitrogen-fixing mutualists may have played a role in increasing population and body size during Attini evolution. A larger population is thought to be associated with increases in infection rates, but this tendency was apparently counterbalanced by high social complexity of leaf-cutters and by the maintenance of Burkholderiales and Actinomycetales species, which we only found in the cuticle of ants. These antibiotic-producing bacteria may have assumed the protective role that is currently attributed to Pseudonocardiaceae in the remaining Attini species. We also detected an association with cuticular Wolbachia mutualists, which may have begun in the more primitive Attini, then specialized in the intermediate ones, and finally being lost in the more derived leaf-cutters. Mutualistic associations appear to be recent and originated from a single acquisition of nitrogen-fixing bacteria and multiple acquisitions of antibiotic producing microbes. / FAPESP: 09/09258-5

Made available in DSpace on 2015-03-03T11:52:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-01-17Bitstream added on 2015-03-03T12:06:24Z : No. of bitstreams: 1 000807225.pdf: 1367113 bytes, checksum: 1b8558d3a715a24a26f71a4de68c3b29 (MD5) / O objetivo deste estudo foi conhecer a composição de espécies de formigas epigéicas, nas diferentes estações climáticas do ano; do estrato arbustivo-arbóreo, bem como avaliar se existe correlação entre porte das plantas e riqueza de espécies de formigas e comparar a mirmecofauna em três estratos verticais (solo, arbustivo e arbóreo), em duas fitofisionomias de Cerrado goiano, no município de Ipameri, GO. Para a realização das coletas, em cada fitofisionomia, foram selecionados 30 pontos de amostragens no solo e 30 plantas entre arbustos e árvores distribuídos ao longo de um transecto medindo cerca de 100 m de comprimento. Em cada ponto foi colocada uma armadilha do tipo pitfall, enterrada ao nível do solo, contendo álcool 50% e em cada planta foram colocados dois tipos de iscas, que consistiram de um copo plástico com capacidade de 110 mL, contendo sardinha e a outra contendo mel. Foram realizadas duas coletas por mês, durante um ano, no período de julho/2011 a junho/2012. Quanto á composição de formigas epigéicas, foram coletadas 51 espécies de formigas na fitofisionomia Cerradão, distribuídas em sete subfamílias e, 48 espécies em Cerrado sentido restrito, distribuídas em seis subfamílias. Houve diferença significativa nas constâncias entre as espécies de formigas, entre as estações do ano e para a interação constância das espécies versus estação do ano, em ambas as fitofisionomias. Por meio de curvas de acumulação de espécies, observou-se que o esforço amostral realizado foi satisfatório nos dois ambientes. A riqueza média de espécies estimada não indicou diferença significativa entre as estações. Com relação á composição de espécies do estrato arbustivo-arbóreo, foram coletadas 40 espécies de formigas, distribuídas em 13 gêneros e seis subfamílias em Cerradão e destas, 23 foram consideradas acidentais (z), 10 constantes (w) e sete acessórias (y). Em Cerrado sentido ... / The aim of this study was to determine the species composition of ants epigaeic, in different seasons of the year; the woody layer, and assess whether there ia a correlation between plant height and species richness of ants and ant fauna compare the three strata vertical (soil, shrubs and trees) in two Cerrado goiano physiognomies, in the municipality of Ipameri, GO. To carry out the collections in each vegetation type, 30 sampling sites and 30 plants in the soil between shrubs and trees distributed along a transect measuring about 100 m in length were selected. At each point a trap was placed pitfall of the type buried ground level, containing 50% alcohol in each plant, and two types of lures, which consisted of a plastic cup with a capacity of 110 ml, containing honey and the other containing sardines were placed. Two samples per month were held for one year, between June/2012 July/2011 to. As to the composition epigaeic ants, were collected 51 species of ants distributed in seven subfamilies in Cerradão and 48 species distributed in six subfamilies in Cerrado sensu stricto. There were significant differences between species in the constancy of ants, between the seasons and the interaction of species constancy versus season in both phytophysiognomies. Through species accumulation curves, it was observed that the sampling effort was achieved in both environments. The species richness values estimated indicated no significant difference between the seasons. With respect to the composition of species of woody layer, were collected 40 ant species, distributed in 13 genera and six subfamilies in Cerradão. Of the 40 species collected, 23 were accidental (z), 10 constants (w) and seven accessory (y). In Cerrado sensu stricto, 36 ant species, distributed in 12 genera and six subfamilies were collected. This phytophysiognomy a larger number of accidental species was also detected (18), followed by 11 species constants and seven accessory ...

abstract: The most abundantly studied societies, with the exception of humans, are those of the eusocial insects, which include all ants. Eusocial insect societies are typically composed of many dozens to millions of individuals, referred to as nestmates, which require some form of communication to maintain colony cohesion and coordinate the activities within them. Nestmate recognition is the process of distinguishing between nestmates and non-nestmates, and embodies the first line of defense for social insect colonies. In ants, nestmate recognition is widely thought to occur through olfactory cues found on the exterior surfaces of individuals. These cues, called cuticular hydrocarbons (CHCs), comprise the overwhelming majority of ant nestmate profiles and help maintain colony identity. In this dissertation, I investigate how nestmate recognition is influenced by evolutionary, ontogenetic, and environmental factors. First, I contributed to the sequencing and description of three ant genomes including the red harvester ant, Pogonomyrmex barbatus, presented in detail here. Next, I studied how variation in nestmate cues may be shaped through evolution by comparatively studying a family of genes involved in fatty acid and hydrocarbon biosynthesis, i.e., the acyl-CoA desaturases, across seven ant species in comparison with other social and solitary insects. Then, I tested how genetic, developmental, and social factors influence CHC profile variation in P. barbatus, through a three-part study. (1) I conducted a descriptive, correlative study of desaturase gene expression and CHC variation in P. barbatus workers and queens; (2) I explored how larger-scale genetic variation in the P. barbatus species complex influences CHC variation across two genetically isolated lineages (J1/J2 genetic caste determining lineages); and (3) I experimentally examined how CHC development is influenced by an individual’s social environment. In the final part of my work, I resolved discrepancies between previous findings of nestmate recognition behavior in P. barbatus by studying how factors of territorial experience, i.e., spatiotemporal relationships, affect aggressive behaviors among red harvester ant colonies. Through this research, I was able to identify promising methodological approaches and candidate genes, which both broadens our understanding of P. barbatus nestmate recognition systems and supports future functional genetic studies of CHCs in ants. / Dissertation/Thesis / Doctoral Dissertation Biology 2016