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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Behavioral ecology of invasive ant species in Hawaiʻi

Kirschenbaum, Ranit January 2007 (has links)
Thesis (M.S.)--University of Hawaii at Manoa, 2007. / Includes bibliographical references (leaves 51-56). / viii, 56 leaves, bound ill. 29 cm
32

Dynamic territoriality for multi-robot systems /

Richer, Toby. Unknown Date (has links)
This thesis proposes a new method of dividing a task between members of a robot team. This method is dynamic territoriality. Territoriality is an emergent method of distributing resources between animals- each animal independently marks and defends their own area. Territoriality has previously been used on robot teams with varying results; these robot territorial systems did little or no adaptation to the environment or task, unlike natural territorial systems. / A dynamic territorial system adapts the territories to fit the environment, and the task the robot team must perform. The algorithm used to generate the territories is a novel extension of the ant clustering algorithm. Given a topological map of the space, it divides a space into a pre-specified number of territories such that the territories have minimal contact and near-equal area. The dynamic territorial algorithm was tested using hand-generated topological maps, then on physical environments. A robot system was developed to traverse an area and generate a topological map usable by the algorithm. / Dynamic territoriality can be used by simple robot teams to organize tasks such as multi- robot cleaning, monitoring and surveillance. The territories divide a complex environment into several simpler environments; this makes many tasks easier to perform. As the dynamic territorial algorithm is designed to minimize connections between territories, robot surveillance teams can capture or track intruders most easily at the territorial boundaries. Predator-prey and robot simulations were used to demonstrate the effectiveness of this territorial system in multi-robot surveillance. / This thesis extends previous work in territorial robotics and biologically inspired algorithms to create a new multi-robot control system. This control system has been implemented in hardware using a new topological mapping system. The thesis shows that this new multi-robot control system can effectively survey an area. In particular, it can control the movement of large groups of targets, or targets that move faster than the robots. / Thesis (PhD)--University of South Australia, 2005.
33

Revision of the ant genus Crematogaster (Hymenoptera : Formicidae) in North America

Morgan, Cynthia Ellen. January 2009 (has links)
Thesis (Ph. D.)--University of Texas at El Paso, 2009. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.
34

Revision of the ant genus Procryptocerus (Hymenoptera: Formicidae: Myrmicinae: Cephalotini)

Serna-Cardona, Francisco Javier. January 2009 (has links)
Thesis (Ph. D.)--University of Texas at El Paso, 2009. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.
35

The relationship between ants (Hymenoptera: Formicidae), vine mealybug (Hemiptera: Pseudococcidae) and parasitoids in vineyards of the Western Cape Province, South Africa /

Mgocheki, Nyembezi. January 2008 (has links)
Dissertation (PhD(Agric)--University of Stellenbosch, 2008. / Bibliography. Also available via the Internet.
36

Distribution and foraging by the leaf-cutting ant Atta cephalotes L. in coffee plantations with different types of management and landscape contexts and alternatives to insecticides for its control /

Varón Devia, Edgar Herney. January 1900 (has links)
Thesis (Ph. D.)--University of Idaho, 2006. / Abstract. "June 2006." Includes bibliographical references. Also available online in PDF format.
37

Comportamento de cuidado da prole da saúva-limão Atta sexdens rubropilosa Forel, 1908 (Hymenoptera, formicidae)

Schneider, Marcelo de Oliveira [UNESP] 13 February 2004 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2004-02-13Bitstream added on 2014-06-13T18:50:42Z : No. of bitstreams: 1 schneider_mo_me_rcla.pdf: 1516192 bytes, checksum: ee654217928eadac803cf99e821d36f0 (MD5) / Um conjunto de microcâmeras e aparelhos para gravação e análise de imagens foi usado para observar, descrever e quantificar os comportamentos de cuidado da prole por parte das operárias adultas da saúva-limão Atta sexdens rubropilosa. Para isso foram utilizadas colônias de laboratório com câmaras especialmente projetadas para a observação do ambiente interior do formigueiro, o jardim de fungo. As microcâmeras utilizadas permitiram que os comportamentos fossem vistos com grande riqueza de detalhes, mostrando-se bastante adequadas para observar pequenos objetos como as menores operárias do formigueiro, e comportamentos que ocorrem em uma pequena área como os propostos neste trabalho. A análise do material filmado em fitas de vídeo possibilitou que comportamentos rápidos fossem facilmente observados e que comportamentos que aconteciam simultaneamente fossem analisados independentemente. Foram descritos diversos comportamentos que ocorrem na área da cria, com suas respectivas freqüências, discutindo-se o papel do tamanho e da idade das operárias na divisão de trabalho. As principais categorias de comportamentos de cuidado da prole observados foram: limpeza dos estágios imaturos pelas operárias adultas, o aprovisionamento das larvas e a ocorrência de trofalaxia no interior do formigueiro. Além disso, uma nova forma de transferência de alimento das larvas para as operárias adultas, denominada trofalaxia proctodeal, foi descrita para Atta. / A set of microcameras and other equipment for recording and image analyses were used to observe, describe and quantify the brood care behaviors of the adult workers of the Lemon Leaf-Cutting Ant Atta sexdens rubropilosa. In order to observe the fungus garden inside the ant colony, laboratory colonies with especially designed observation chambers were used. The microcameras enabled the behaviors to be observed in great detail, proving themselves to be very adequate for the observation of small objects such as the smallest workers, as well as behaviors occurring on a small area as the ones proposed in this work. The analyses of the material recorded on videotapes made it easier to follow fast behaviors and to independently analyze distinct behaviors happening simultaneously. Several behaviors occurring around the brood are described with their respective frequencies. The role of worker age and size on the division of labor are discussed. The main categories of brood care behavior observed were: grooming of the immature stages by the adult workers, larval feeding and the occurrence of trophalaxis in the colony. A new means of food transfer from the larvae to the adult workers, named proctodeal trophalaxis was also described.
38

Microbioma de formigas com ênfase em Camponotini (Hymenoptera, Formicidae) /

Ramalho-Sanchez, Manuela de Oliveira. January 2017 (has links)
Título original: Comunidades de bactérias de dois gêneros de formigas Polyrhachis (Spiny ants) e camponotus (Carpenter ants) / Orientador: Odair Correa Bueno / Coorientadora: Corrie Saux Moreau / Banca: Fernando Carlos Pagnocca / Banca: Cíntia Martins Perinotto / Banca: James Montoya Lerme / Banca: Priscila Cintra Socolowski / Resumo: A interação simbiótica tem sido uma das responsáveis pela evolução e a biodiversidade de espécies existentes no planeta. Mais estudos abordando diferentes hospedeiros mostram-se necessários para aumentar o conhecimento do significado evolutivo desta associação na natureza. As formigas pertencentes aos gêneros Polyrhachis e Camponotus estão contidas na tribo Camponotini e são estreitamente relacionadas além de possuírem ampla distribuição, hábitos diversificados, e estão frequentemente associadas à endossimbiontes. Entretanto existem poucos estudos nesta área, permanecendo então muitas questões a respeito destas associações. Desta maneira, por meio da técnica de Sequenciamento de Nova Geração (NGS) Illumina MiSeq2000, o presente estudo teve como objetivo: I. explorar a comunidade microbiana de diversas espécies de Polyrhachis distribuídas em toda sua extensão e verificar os fatores que a influenciam. II. caracterizar a comunidade bacteriana associada aos gêneros Colobopsis e Camponotus, e analisar se há diferenças na composição da comunidade bacteriana quando comparada entre os diferentes gêneros, colônias e em todos os estágios de desenvolvimento; III. averiguar como se dá a distribuição da comunidade bacteriana nas diferentes partes do corpo (cabeça, mesossoma e gáster) de Camponotus, e se esta diversidade está associada ao ambiente onde estas Camponotus foram coletadas; IV. caracterizar o ovário de Camponotus textor, utilizando técnicas de histologia (HE), documentar a ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Symbiotic interaction has been one of the factors responsible for the evolution and biodiversity of species on the planet. More studies addressing different hosts are necessary to increase the knowledge of the evolutionary meaning of this association in nature. The ants belonging to the genera Polyrhachis and Camponotus are contained in the Camponotini tribe and they are closely related in addition to having wide distribution, diversified habits, and are often associated with endosymbionts. However, there are few studies in this area, and many questions remain about these associations. In this way, through the New Generation Sequencing technique (NGS) Illumina MiSeq2000, the present study aimed: I. To explore the microbial community of several species of Polyrhachis distributed throughout its range and to verify the factors that influence it. II. Characterize the bacterial community associated with the genus Colobopsis and Camponotus, and analyze if there are differences in the composition of the bacterial community when compared between different genera, colonies and at all stages of development; III. To determine how the distribution of the bacterial community occurs in the different parts of the body (head, mesosome and gaster) of Camponotus, and if this diversity is associated with the environment where these Camponotus were collected; IV. To characterize the ovary of Camponotus textor using histology techniques (HE), to document the location of Blochmannia and Wolbachia in oogenesis by fluorescence in situ hybridization (FISH), and to suggest the mechanism of development that these bacteria use to reach the egg . These studies have demonstrated that there are several factors that can influence the ant-associated bacterial community, such as host phylogeny, genera, colony, ontogeny, different body parts, and the environment the ant was ... (Complete abstract click electronic access below) / Doutor
39

Determinação de cepas de Wolbachia em populações naturais de Solenopsis spp. (Hymenoptera: Formicidae) analisadas via Multilocus Sequence Typing (MLST): diversidade genética, coevolução e recombinação

Martins, Cíntia [UNESP] 02 July 2014 (has links) (PDF)
Made available in DSpace on 2016-02-05T18:30:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-07-02. Added 1 bitstream(s) on 2016-02-05T18:34:13Z : No. of bitstreams: 1 000857534.pdf: 1229333 bytes, checksum: 4a0683950d7b91d5ae07474bfd3e39ef (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo a Pesquisa do Estado do Piauí (FAPEPI) / Interações insetos/micro-organismos são amplas e ocorrem das mais diversas maneiras, com as bactérias simbiontes de insetos desempenhando vários papéis, na maioria desconhecidos, na biologia do hospedeiro. O que se considerava apenas um único organismo eucariótico é na verdade um agregado de vários diferentes organismos, o que levou a uma mudança na maneira de se estudar esses organismos, culminando em uma abordagem mais holística. Dentro desse vasto mundo, relativamente pouco conhecido dos micro-organismos em associação com insetos, estão as bactérias do gênero Wolbachia (Classe Alphaproteobacteria, Ordem Rickettsiales), amplamente distribuídas nos artrópodes e transmitidas maternalmente, causadoras de diversas alterações reprodutivas no hospedeiro, sendo que sua ocorrência em populações naturais pode ser de grande interesse no controle biológico. A distribuição dessas bactérias em formigas é pouco explorada e existe carência de informações sobre a interação com formigas do gênero Solenopsis, que inclui espécies nativas da América do Sul. Este gênero possui espécies distribuídas de forma cosmopolita e no Brasil estão amplamente disseminadas, associadas preferencialmente a áreas de atividade humana. Este trabalho teve como objetivo analisar a diversidade genética da Wolbachia de amostras de ninhos de populações nativas de espécies do gênero Solenopsis, através do sequenciamento de cinco genes que compõe o multilocus de Wolbachia, além do gene wsp, a fim de caracterizar as cepas e estabelecer inferências filogenéticas entre elas. Além disso, testar as hipóteses de coevolução entre as cepas e as formigas e de recombinação entre as cepas encontradas. Com o sequenciamento e análises dos cinco genes que compõem o multilocus de Wolbachia (gatB, coxA, hcpA, ftsZ e fbpA), totalizando 2079 pb, destacam-se os seguintes resultados: i. o registro de 15 novas cepas; ii. o registro de 11 alelos... / Insects/microorganisms interactions are broad and occurs in many different ways with symbiont bacteria of insects playing many roles, most unknown, on the biology if its host. What was considered a single eukaryotic organism is actually an aggregate of many different organisms which lead to a change in the way we study organisms, leading to a more holistic approach. Within this vast but relatively unknown world of microorganisms in association with insects are the bacteria of the genus Wolbachia (Class Alphaproteobacteria, Order Rickettsiales) widely distributed in arthropods and maternally transmitted, causing several reproductive alterations in the host, and their occurrence in natural populations being of great interest in the biological control of insects. Its distribution in ants is poorly explored and little is known about the interaction with the Solenopsis genus which includes native species from South America. This genus includes species cosmopolitan distributed and in Brazil they are widely distributed being preferentially associated with areas of human activity. This study aimed to analyze the genetic diversity of samples of nests from native populations of Solenopsis species infected by Wolbachia by sequencing the five genes comprising the Wolbachia multilocus, and also the wsp gene in order to characterize the strains and establish phylogenetic inferences between them. Furthermore test the hypothesis of coevolution between ants and its Wolbachia strains and recombination between found strains. With the sequencing and analysis of five genes comprising the Wolbachia multilocus (gatB, coxA, hcpA, ftsZ e fbpA) totaling 2079 bp the following results are highlighted: i. the record of 15 previously unknown new strains, ii. the record of 11 previously unknown new alleles, iii. phylogenetic relationship between the strains found here presents a polyphyletic pattern, indicative of the complexity of the evolutionary history of strains ...
40

Streptomyces associados a formigas da tribo Attini e seus efeitos sobre os fungos Escovopsis weberi e outros microrganismos

Favarin, Etienne Cristina [UNESP] 15 December 2005 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-12-15Bitstream added on 2014-06-13T19:14:52Z : No. of bitstreams: 1 favarin_ec_me_rcla.pdf: 436560 bytes, checksum: 985e56580dc75e41c059cd89ca7f4655 (MD5) / A simbiose entre as formigas cortadeiras e seu fungo originou-se a aproximadamente 50 milhões de anos. A diversidade biótica dos formigueiros, no entanto, não se restringe apenas à formiga e ao fungo simbionte. Recentemente foi descoberto um terceiro mutualista, uma bactéria filamentosa do grupo dos actinomicetos, cuja principal função seria a inibição do crescimento de parasitas do jardim de fungos, especialmente o fungo conhecido como Escovopsis sp, através da produção de antibióticos. O presente trabalho teve como objetivos verificar o potencial das linhagens de Streptomyces, que foram isoladas de Attini, como produtoras de substâncias antimicrobianas frente aos fungos Escovopsis weberi e outros microrganismos e também a caracterização dessas linhagens através de técnicas de biologia molecular. Foram selecionadas nove linhagens de Streptomyces, que foram cultivadas em meio SCN líquido, para a obtenção dos filtrados. Para os ensaios de antibiose envolvendo os fungos Escovopsis weberi, foram testadas diferentes concentrações de filtrados adicionadas ao meio A sólido e foi verificada a porcentagem de germinação dos conídios em cada concentração. Para a determinar a atividade dos filtrados frente as bactérias e leveduras, os testes foram realizados pelo método de difusão em agar. Os resultados mostraram que, mesmo variando os filtrados obtidos das linhagens de Streptomyces, a inibição da germinação dos conídios foram muito semelhantes, e todas as linhagens do fungo Escovopsis weberi apresentaram uma inibição homogênea frente a mesma concentração de filtrado. Com relação as bactérias e leveduras, os resultados mostraram que houve diferenças na intensidade da resposta. Algumas linhagens inibiram o crescimento de todas as bactérias e leveduras testadas, outras não inibiram apenas algumas culturas e teve linhagens que não inibiram nenhuma das... / The symbiotic relationship between leaf-cutting ants (Tribe Attini) and their mutualistic fungus probably arose fifty million years ago. However, these two organisms are at least, part of the biological diversity found in nests of these insects. Recently, it was discovered a third mutualist, an antibioticproducing actinomycete, which is used by the ants to control the development of garden parasites, specially within the microfungus genus Escovopsis sp. In order to determine which isolates of this actinomycete could affect the growth of Escovopsis weberi and other microorganisms; nine strains of Streptomyces sp. were grown in liquid SCN and the resultant media (extract) were filtered and used in the experiments. Also, all actinomycete strains were characterized by molecular sequencing of the 16 rDNA region. In the assays involving E. weberi, different extract amounts were added into solid medium (Meio A) and the conidial germination rate were determined after incubation. Disk-difusion method were used to verify the antimicrobial activity of these extracts over a large range of bacteria and yeasts. In spite of the concentration used in E. weberi assays, inhibiton of spore germination was achieved and this response was similiar among E. weberi isolates. On the other hand, bacteria and yeasts demostrated a high degree variability in this response. Some Streptomyces sp. strains inhibited all bacteria and yeasts tested, but other just inhibited a few of them. The molecular sequencing of the 16S rDNA region have shown that all actinomycete strains used in this work were grouped with other Streptomyces species found in GenBank. In spite of phylogenetic analyses have grouped Attini isolates in different clades, the activity of the antimicrobial compounds produced by these bacteria had a high degree of homogenicity over E. weberi... (Complete abstract, click electronic address below)

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