• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 3
  • 1
  • 1
  • Tagged with
  • 5
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 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.
1

Paarungshäufigkeit und Aufteilung der Reproduktion bei Pachycondyla villosa / Mating frequency and partitioning of reproduction in Pachycondyla villosa

Trunzer, Brigitte January 1999 (has links) (PDF)
In Ameisensozietäten treten häufig Konflikte um die Reproduktion auf. Um dabei das soziale Verhalten der beteiligten Individuen und die Koloniestruktur zu verstehen ist es wichtig, die Verwandtschaftsstruktur innerhalb der Kolonien zu kennen. Diese wird durch die Paarungshäufigkeit der Königinnen, die Anzahl der Königinnen im Nest, deren Verwandtschaftsgrad zueinander, sowie der Aufteilung der Reproduktion zwischen ihnen bestimmt. Bei Pachycondyla villosa wurden durch die genetische Analyse dieser Faktoren mittels Multilokus-DNA- Fingerprinting das Paarungssystem und die Koloniestruktur genauer untersucht. Die Bestimmung der Paarungshäufigkeit ergab, daß sich P. villosa-Königinnen nur einmal paaren. Befanden sich mehrere Königinnen in einem Nest, so waren sie nicht miteinander verwandt und die Reproduktion war gleichmäßig zwischen ihnen aufgeteilt. Im Gegensatz zu den polygynen Kolonien von P. villosa traten in königinlosen Arbeiterinnengruppen zwischen den assoziierten Tieren heftige Konflikte um die Reproduktion auf. Diese führten zur Etablierung linearer Dominanzhierarchien und die Alpha-Tiere waren bei der Produktion von Männchen am erfolgreichsten. Betreuer Hölldobler, Berthold; Prof. Dr. Gutachter Hölldobler, Berthold; Prof. Dr. Gutachter Heinze, Jürgen; Prof. Dr. / In ant societies there are often conflicts over reproduction. Therefore, to understand the social behavior and the structure of the colony, it is essential to know the kin structure within the colonies. Kin structure is affected by the mating frequency of queens, the number and relatedness of queens and the allocation of reproduction between them. In Pachycondyla villosa, the mating system and the colony structure was determined by analyzing these factores genetically with multilocus DNA fingerprinting. The examination of the mating frequency showed, that queens of P. villosa only mate once. In the presence of more than one queen in the nest, the associated queens were not related and reproduction was evenly shared. In contrast to the polygynous colonies overt conflicts over reproduction occured in queenless worker groups of P. villosa. By that linear dominance hierarchies were established and the alpha-workers were most successful in producing males.
2

Molecular Phylogenetics and Taxonomic Revision of Ponerine Ants (Hymenoptera: Formicidae: Ponerinae)

Schmidt, Chris Alan January 2009 (has links)
I report the results of the first detailed phylogenetic study of the ant subfamily Ponerinae, a diverse lineage whose properties make it an attractive model system for investigating social and ecological evolution in ants. Molecular sequence data were obtained from seven nuclear genes for 86 ponerine taxa, representing all three ponerine tribes, 22 of the 28 currently recognized genera, and 14 of the 18 informal subgenera of Pachycondyla, a genus strongly suspected to be non-monophyletic. Divergence dates, historical biogeography, and the origin of reproduction by gamergate workers were estimated on the inferred phylogeny. The most important results of this study include: (1) the monophyly of Ponerinae; (2) the paraphyly of Ponerini; (3) the extensive non-monophyly of Pachycondyla; (4) a rapid basal radiation in Ponerini; (5) resolution of many deeper relationships within Ponerini; (6) a rapid and rich basal radiation in the Odontomachus group; (7) an origin for Ponerinae in the upper Cretaceous, with a major burst of diversification near the K/T boundary; (8) a history of rich and continual ponerine diversification during the Cenozoic; (9) a history of regionalized radiations and frequent faunal exchange between major biogeographic provinces; and (10) support for multiple origins of gamergates in Ponerinae. Ponerine taxonomic classification is revised to reflect both these phylogenetic results and a reappraisal of ponerine morphological diversity. The monogeneric tribe Thaumatomyrmecini is newly synonymized under Ponerini, and the diverse genus Pachycondyla is fragmented into 15 genera, largely along the lines of its junior synonyms, though two new genera are erected: Buniapone (gen. nov.) and Mayaponera (gen. nov.). Some junior synonyms of Pachycondyla are transferred to junior synonym status under other genera: Wadeura as a junior synonym of Cryptopone (syn. nov.), Xiphopelta as a junior synonym of Pseudoponera (syn. nov.), and both Termitopone and Syntermitopone as junior synonyms of Neoponera (syn. nov.). Molecular and morphological justifications for these taxonomic changes are given alongside discussions of phylogenetic relationships. Keys to the world genera of Ponerinae are provided, and morphological diagnoses and species lists are given for each genus. Finally, the available information on ponerine ecology and behavior is reviewed and synthesized.
3

Tomada de decis?o individual e aprendizado em Dinoponera quadr?ceps (Ponerinae, Hymenoptera) forrageando em ambientes din?micos

Silva Neto, Waldemar Alves da 26 August 2014 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-03-02T23:16:56Z No. of bitstreams: 1 WaldemarAlvesDaSilvaNeto_DISSERT.pdf: 468163 bytes, checksum: f08e3ba40bea69faf17f824fa2df41be (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-03-04T23:52:21Z (GMT) No. of bitstreams: 1 WaldemarAlvesDaSilvaNeto_DISSERT.pdf: 468163 bytes, checksum: f08e3ba40bea69faf17f824fa2df41be (MD5) / Made available in DSpace on 2016-03-04T23:52:21Z (GMT). No. of bitstreams: 1 WaldemarAlvesDaSilvaNeto_DISSERT.pdf: 468163 bytes, checksum: f08e3ba40bea69faf17f824fa2df41be (MD5) Previous issue date: 2014-08-26 / No presente trabalho, avaliamos o efeito da dist?ncia do alimento, sucesso de captura e tamanho do alimento e taxa de recompensa nas decis?es de forrageio tomadas por formigas da esp?cie Dinoponera quadriceps. Tamb?m investigamos, medindo o tempo de perman?ncia em cada ?rea, a influ?ncia do aprendizado no desempenho das oper?rias ao longo de sucessivas viagens. Foram simulados quatro cen?rios. Cada oper?ria realizou 10 viagens em cada cen?rio. Cen?rio 1: oper?rias sempre encontravam alimento de alta qualidade; Cen?rio 2: oper?rias encontravam alimento de alta qualidade em somente 50% das viagens; Cen?rio 3: oper?rias encontravam alimento de alta e baixa qualidade com probabilidades de ocorr?ncia de 0,5 para cada tamanho de alimento. Cen?rio 4: oper?rias tinham tr?s possibilidades, encontrar alimento de alta qualidade (33%), encontrar alimento de baixa qualidade (33%) e n?o encontrar alimento. Em todos os cen?rios, havia duas rotas poss?veis de explora??o, uma com 300 cm e outra com 600 cm de comprimento. A pesquisa mostrou que oper?rias da esp?cie D. quadr?ceps tendem a retornar ao mesmo local onde o alimento foi encontrado na viagem anterior, n?o importando a dist?ncia, tamanho do alimento ou taxa de recompensa. Nos casos de viagens sem captura, oper?rias eram mais propensas a trocar de ?rea em busca de alimento. No entanto, no cen?rio 4 essa decis?o de ?troca? foi menos evidente, possivelmente pela maior din?mica do cen?rio. Resultados tamb?m indicaram um processo de aprendizado das rotas de explora??o assim como das condi??es das ?reas de explora??o. Com a repeti??o das viagens, forrageadoras reduziram o tempo de busca nas ?reas nas viagens que n?o capturavam alimento e rapidamente trocavam de ?rea. / When searching for food, animals often make decisions of where to go, how long to stay in a foraging area and whether or not to return to the last visited spot. These decisions can be enhanced by cognitive traits and adjusted based on previous experience. In social insects such as ants, foraging efficiency have an impact on both individual and colony level. The present study investigated, in the laboratory, the effect of distance from food, capture success and food size, and reward rate on decisions of where to forage in Dinoponera quadriceps, a ponerine ant that forage solitarily and individually make their foraging decisions. We also investigated the influence of learning on the performance of workers over successive trips searching for food by measuring the patch residence time in each foraging trip. Four scenarios were created differing in food reward rates, food size offered and distances colony-food site. Our work has shown that as a rule-of-thumb, workers of D. quadriceps return to the place where a prey item was found on the previous trip, regardless of distance, food size and reward rate. When ants did not capture preys, they were more likely to change path to search for food. However, in one of the scenarios, this decision to switch paths when unsuccessful was less evident, possibly due to the greater variation of possible outcomes ants could experience in this scenario and cognitive constraints of D. quadriceps to predict variations of food distribution. Our results also indicated a learning process of routes of exploration as well as the food site conditions for exploration. After repeated trips, foragers reduced the patch residence time in areas that they did not capture food and quickly changed of foraging area, increasing their foraging efficiency.
4

Estudos citogenéticos de espécies da tribo Ectatommini (Hymenoptera: Formicidae: Ponerinae) / Cytogenetic studies on species of the tribe Ectatommini (Hymenoptera: Formicidae: Ponerinae)

Borges, Davileide de Sousa 21 March 2003 (has links)
Submitted by Reginaldo Soares de Freitas (reginaldo.freitas@ufv.br) on 2017-03-21T19:05:44Z No. of bitstreams: 1 texto completo.pdf: 534718 bytes, checksum: 5457b363ed599b6274f4181bf1465bb8 (MD5) / Made available in DSpace on 2017-03-21T19:05:44Z (GMT). No. of bitstreams: 1 texto completo.pdf: 534718 bytes, checksum: 5457b363ed599b6274f4181bf1465bb8 (MD5) Previous issue date: 2003-03-21 / Fundação de Amparo à Pesquisa do Estado de Minas Gerais / Com o objetivo de contribuir ao conhecimento da citogenética da tribo Ectatommini (Hymenoptera; Formicidae; Ponerinae) na Região Neotropical, foram analisados os cariótipos de formigas dos gêneros Gnamptogenys, Heteroponera e Ectatomma. As colônias foram coletadas nas reservas da Mata do Paraíso e da Mata da Biologia em Viçosa/MG, assim como em áreas experimentais da CEPLAC/CEPEC, em Ilhéus/BA. O uso de técnicas citogenéticas proporcionou a caracterização numérica e morfológica dos cromossomos dos cariótipos estudados. Estes variaram de 2n=24-68: Gnamptogenys striatula 2n=34 (24M+10A); Gnamptogenys sp., n=23 (9M+14A), 2n=46 (18M+28A); G. annulata 2n=68 (6M+62A); Heteroponera dolo 2n=24 (22M+2A); Ectatomma tuberculatum 2n=36 (30M+6A); E. brunneum 2n=44 (22M+22A) e E. edentatum 2n=46. Não foram observadas diferenças entre os cariótipos de duas populações distintas de Gnamptogenys striatula (Viçosa/MG e Ilhéus/BA), mostrando a grande estabilidade cariotípica desta espécie. Uma análise de variância das fórmulas cariotípicas de nove espécies da tribo Ectatommini (incluindo informações sobre duas espécies disponíveis na literatura) demonstrou que a razão de cromossomos metacêntricos (M) para acrocêntricos (A) diminuiu proporcionalmente ao aumento do número de cromossomos (n), sugerindo, portanto, rearranjos do tipo fissão. O método cariográfico demonstrou uma relação entre número cromossômico (n) e o número de braços (AN) levando a hipotetizar que rearranjos do tipo fissão e inversão foram as principais responsáveis pela diferenciação dos cariótipos na tribo Ectatommini, corroborando a Teoria da Interação Mínima. Entretanto, os dados ainda são escassos, necessitando o estudo de um maior número de espécies e a adaptação de técnicas de bandamentos cromossômicos para elucidar os mecanismos de evolução dos cromossomos nessa tribo. / Aiming to contribute to the knowledge of the tribe Ectatommini cytogenetics (Hymenoptera; Formicidae; Ponerinae) in Neotropical Region, the karyotypes of ants of the Gnamptogenys, Heteroponera and Ectatomma genera were analysed. Colonies were collected in the reserves of Mata do Paraíso and Mata da Biologia, at Viçosa/MG; and in CEPLAC/CEPEC experimental areas, at Ilhéus/BA, Brazil. The use of cytogenetic techniques allowed characterising the karyotypes chromosome numbers and morphology. These varied from 2n=24-68: Gnamptogenys striatula 2n=34 (24M + 10A); Gnamptogenys sp., n=23 (9M + 14A), 2n=46 (18M + 28A); G. annulata 2n=68 (6M + 62A); Heteroponera dolo 2n=24 (22M + 2A); Ectatomma tuberculatum 2n=36 (30M + 6A), E. brunneum 2n=44 (22M + 22A) and E. edentatum 2n=46. No difference was observed between the karyotypes of two distinct populations of Gnamptogenys striatula (Viçosa/MG and Ilhéus/BA), showing the great karyotypical stability of this species. A variance analyse of the karyotype formula of nine species of the Ectatommini tribe (including information on more two species available from literature) showed that, the ratio of metacentrics (M) to acrocentrics (A) chromosomes decreased proportionally to the increase of chromosome number (n) suggesting thus fission rearrangements. The kariograph method showed that exists a relation between chromosome (n) and arm numbers (AN), making possible to formulate the hypothesis that fission and inversion rearrangements are the main responsible of karyotype differentiation in the tribe Ectatommini, according the Minimum Interaction Theory. However, data are still scarce and make necessary the study of a larger number of species as well as adaptation of chromosome-banding techniques in the aim to elucidate the mechanisms of chromosome evolution in the tribe. / Não foi localizado o cpf do autor.
5

Diversidade e composição de formigas Ponerines (Hymenoptera, Formicidae, Ponerinae) de Serapilheira na Estação Científica Ferreira Penna, Caxiuanã, Melgaço, Pará, Brasil

BASTOS, Alexandro Herbert dos Santos 21 May 2009 (has links)
Submitted by Edisangela Bastos (edisangela@ufpa.br) on 2013-03-05T19:30:03Z No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_DiversidadeComposicaoFormigas.pdf: 650256 bytes, checksum: 8698d3a03ce23cda2e3f69d8195c68d4 (MD5) / Approved for entry into archive by Ana Rosa Silva(arosa@ufpa.br) on 2013-03-07T16:32:53Z (GMT) No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_DiversidadeComposicaoFormigas.pdf: 650256 bytes, checksum: 8698d3a03ce23cda2e3f69d8195c68d4 (MD5) / Made available in DSpace on 2013-03-07T16:32:53Z (GMT). No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_DiversidadeComposicaoFormigas.pdf: 650256 bytes, checksum: 8698d3a03ce23cda2e3f69d8195c68d4 (MD5) Previous issue date: 2009 / Inventários da mesofauna de solo e serapilheira em florestas tropicais apresentam a subfamíliaC (Hymenoptera, Formicidae) como uma das mais conspícuas e a segunda com maior riqueza e abundância, depois da subfamília Myrmicinae. Nestes ambientes, as ponerines constituem componentes ecologicamente importantes, onde são notáveis predadoras de outros invertebrados e podem nidificar nos troncos em decomposição ou na serapilheira. Este estudo foi realizado com a intenção de investigar a distribuição espacial das espécies de formigas da subfamília Ponerinae associadas à serapilheira, considerando sua abundância, riqueza, diversidade e composição, em seis áreas de floresta primária (Áreas I, II, III, IV, V e VI) na Estação Científica Ferreira Penna (ECFPn), Caxiuanã, Melgaço, Pará; e como a quantidade de serapilheira influencia nessa distribuição. Este estudo resulta de três coletas realizadas pelo Protocolo de Monitoramento de Formigas do Projeto TEAM/Caxiuanã entre abril de 2003 e janeiro de 2004. Coletaram-se 720 sub-amostras de 1 m² de serapilheira, distribuídas em 72 transectos de 100 m (unidade amostral) entre as seis áreas durante as coletas (quatro transectos por área em cada coleta), utilizando extratores de mini-Winkler. Identificaram-se 4.031 exemplares, pertencentes às três tribos, oito gêneros e 60 espécies de Ponerinae em 470 registros, sendo que o número médio de espécies por amostra foi de 6,52, e estimou-se encontrar 81 espécies (Jackknife 1). Hypoponera foi o gênero com maior abundância (268 registros) e riqueza de espécies (22), compreendendo junto com Pachycondyla mais de 70% das espécies. A Área V apresentou maior diversidade (H= 3,30), abundância (121) e riqueza (38) em espécies, além de maior volume de serapilheira (ANOVA; p<0,05 entre a Área V e as demais). A quantidade de serapilheira afetou positivamente a abundância e a riqueza de espécies, e também influenciou na composição de espécies. As espécies mais freqüentes (abundantes) nas amostras foram Hypoponera sp#1, Hypoponera sp#2, Hypoponera sp#6, Hypoponera sp#7, dontomachus scalptus e Pachycondyla constricta, que juntas representaram mais de 50% da abundância total. No geral, as ponerines apresentaram ampla distribuição na serapilheira de floresta primária na ECFPn, sendo numericamente influenciadas pela quantidade de serapilheira; as áreas apresentaram diferenças na diversidade, abundância e riqueza das espécies encontradas; e, como efeito do elevado número de espécies raras, encontrou-se baixa similaridade na composição de espécies entre amostras próximas; logo, mesmo em pequena escala, a heterogeneidade da camada de serapilheira na floresta amazônica tem importante papel na distribuição das espécies. / The ponerines, after myrmicines, are the most conspicuous, rich and abundant ground-dwelling ants from tropical rain forests. In this ecosystem the ponerines are ecologically important, since they prey many kinds of invertebrates and nest among leaf litter and rotten logs. In this work the range of leaf litter Ponerinae ants was studied, as well their abundance, richness, diversity, and species composition. In addition, how the litter quantity affect the ponerines range was analyzed. This study was carried out in six primary Amazonian forest areas of 1 Km² (Area I, II, III, IV, V, and VI) at Ferreira Penna Scientific Station (ECFPn), Caxiuanã, Melgaço, Pará state, Brazil. The material was collected at April and October of 2003, and January of 2004, following the Ants Monitoring Protocol of TEAM Iniciative/Caxiuanã Project for the study of leaf litter ants. In each sampled site four transects lines of 100 m (sample units) with 10 samplings points were established. At each sampling point of 1 m², the leaf litter samples were sifted and then placed in mini-Winkler sacks. A total of 4,031 specimens were collected, belonging to three tribes, eight genera, and 60 species of Ponerinae in 470 records. In average 6.52 species were collected per sample. The total richness was estimated in 81 species using first order Jackkinife method. Hypoponera was the most abundant and rich genus, with 22 species in 268 records. The genus Hypoponera plus Pachycondyla showed a strong numerical dominance, with more than 70% of collected species. The Area V was the most diverse (H=3.30), with the highest species richness (38) and abundance (121 records), as well as with the largest amount of leaf litter (ANOVA; p<0,05 between Area V and the other sites). The quantity of leaf litter affected positively the ponerines ants species abundance and richness, and also influenced the species composition. The most common species were: Hypoponera sp#1, Hypoponera sp#2, Hypoponera sp#6, Hypoponera sp#7, Odontomachus scalptus and Pachycondyla constricta. These few species (10%) yielded more than half of total abundance. In short, the ponerines were widely spread in the leaf litter of ECFPn primary forests, being numerically affected by leaf litter volume. The sites showed differences in species diversity, abundance and richness. Furthermore, the species composition of ponerines ants at nearby samples often presented low similarity once high number of species was rare. Thus, the leaf litter availability of Amazonian forest is a key role on species distribution, even at small scales.

Page generated in 0.0764 seconds