The Experts below are selected from a list of 1674 Experts worldwide ranked by ideXlab platform
Bert Holldobler - One of the best experts on this subject based on the ideXlab platform.
-
Colony and population structure in Pachycondyla cf. inversa, a ponerine ant with primary polygyny
Ethology Ecology & Evolution, 2002Co-Authors: K. Kolmer, Bert Holldobler, Jürgen HeinzeAbstract:Queens of the neotropical ponerine Pachycondyla cf. inversa may found their colonies co-operatively (pleometrosis) and still co-exist when the colony becomes mature (primary polygyny). We investigated the genetic structure of colonies from a Brazilian population by using microsatellites. In both queens and workers, inbreeding coefficients were significantly different from zero. No evidence for a geographical substructuring of the population was found. Heterozygote deficiency can probably be explained by a temporal substructure of the population, i.e. mating in temporally distinct mating swarms. Nestmate queens were typically not related. A comparison of the microsatellite genotypes of queens and workers indicated that some queens were multiply inseminated.
-
Chemical profiles, division of labor and social status in Pachycondyla queens (Hymenoptera: formicidae).
Die Naturwissenschaften, 2001Co-Authors: J. Tentschert, Jacques H C Delabie, Bert Holldobler, Hans‐jürgen Bestmann, K. Kolmer, Jürgen HeinzeAbstract:Queens of the neotropical ponerine ant Pachycondyla cf. 'inversa' may co-operate during colony founding. One of several co-founding queens specializes in foraging, whereas the others remain in the nest and guard the brood. Division of labor is achieved by aggressive interactions, which result in the formation of dominance hierarchies. Gas chromatography and mass spectrometry of cuticular hydrocarbons obtained from live queens by SPME revealed consistent differences between the patterns of cuticular hydrocarbons of queens with high versus low rank: only high-ranking queens showed considerable amounts of cuticular pentadecane (n-C15) and heptadecene (n-C17:1). These two substances presumably originate from the queens' Dufour glands.
-
a trail pheromone component of the african stink ant Pachycondyla paltothyreus tarsata fabricius hymenoptera formicidae ponerinae
Chemoecology, 1999Co-Authors: Edelgard Janssen, Bert Holldobler, H J BestmannAbstract:The African stink ants (Pachycondyla tarsata) lay recruitment trails with secretions from sternal glands. The glandular secretions consist of 10 compounds, 9 of which have been chemically identified. One of the substances, 9-heptadecanone, elicits trail following behavior in P. tarsata workers that have before been stimulated by a sucessful scout ant.
-
Communication in the migratory termite-hunting ant Pachycondyla (= Termitopone) marginata (Formicidae, Ponerinae)
Journal of Comparative Physiology A, 1996Co-Authors: Bert Holldobler, Paulo S. Oliveira, Inara R. Leal, Edelgard Janssen, Hans‐jürgen Bestmann, F. Kern, Wilfried A. KönigAbstract:The Neotropical species Pachycondyla marginata conducts well-organized predatory raids on the termite species Neocapritermes opacus and frequently emigrates to new nest sites. During both activities the ants employ chemical trail communication. The trail pheromone orginates from the pygidial gland. Among the substances identified in the pygidial gland secretions, only citronellal was effective as a trail pheromone. Isopulegol elicited an increase in locomotory activity in the ants and may function as a synergist recruitment signal. The chemical signal is enhanced by a shaking display performed by the recruiting ant.
-
communication in the migratory termite hunting ant Pachycondyla termitopone marginata formicidae ponerinae
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 1996Co-Authors: Bert Holldobler, Paulo S. Oliveira, Inara R. Leal, Edelgard Janssen, H J Bestmann, F. Kern, Wilfried A. KönigAbstract:The Neotropical species Pachycondyla marginata conducts well-organized predatory raids on the termite species Neocapritermes opacus and frequently emigrates to new nest sites. During both activities the ants employ chemical trail communication. The trail pheromone orginates from the pygidial gland. Among the substances identified in the pygidial gland secretions, only citronellal was effective as a trail pheromone. Isopulegol elicited an increase in locomotory activity in the ants and may function as a synergist recruitment signal. The chemical signal is enhanced by a shaking display performed by the recruiting ant.
Inara R. Leal - One of the best experts on this subject based on the ideXlab platform.
-
Seasonal patterns in the orientation system of the migratory ant Pachycondyla marginata
Die Naturwissenschaften, 2001Co-Authors: Daniel Acosta-avalos, Darci M. S. Esquivel, Eliane Wajnberg, Henrique Lins De Barros, Paulo S. Oliveira, Inara R. LealAbstract:Route directions of migrations by the neotropical termite-hunting ant Pachycondyla marginata at a forest reserve in Southeast Brazil were analysed by circular statistic. Colony movement patterns were compared between the rainy/hot and dry/cold seasons. Migrations during the dry/cold season are significantly oriented 13° with the magnetic North–South axis, while rainy/hot migrations do not exhibit a preferred direction. This result is discussed considering the hypothesis that P. marginata ants may use the geomagnetic field as an orientation cue for migrations in the dry/cold season. The presence of magnetic iron oxides in the head and abdomen of P. marginata is consistent with this suggestion.
-
Isolation of magnetic nanoparticles from Pachycondyla marginata ants
The Journal of Experimental Biology, 1999Co-Authors: Daniel Acosta-avalos, Eliane Wajnberg, Paulo S. Oliveira, Inara R. Leal, M. Farina, Darci M. S. EsquivelAbstract:We report on the presence of magnetic iron oxides in the migratory ant Pachycondyla marginata. Magnetic particles were extracted from different parts of the ant (head, thorax and abdomen) using magnetic precipitation methods. Electron spectroscopic images for iron and oxygen were obtained from the extracted particles, and, by using the corresponding electron micrographs, histograms of size distribution were constructed. Selected area diffraction patterns were also obtained from the particles, and analysis of these showed the presence of a mixture of different iron oxides, including the magnetic oxides, magnetite and maghemite. The size distribution of the particles in the abdomen is different from that in the thorax and the head. In accordance with the hypothesis of magnetic orientation based on the presence of magnetic material within the body, two regions of the ant, the head and the abdomen, could be implicated in the detection of the geomagnetic field.
-
Communication in the migratory termite-hunting ant Pachycondyla (= Termitopone) marginata (Formicidae, Ponerinae)
Journal of Comparative Physiology A, 1996Co-Authors: Bert Holldobler, Paulo S. Oliveira, Inara R. Leal, Edelgard Janssen, Hans‐jürgen Bestmann, F. Kern, Wilfried A. KönigAbstract:The Neotropical species Pachycondyla marginata conducts well-organized predatory raids on the termite species Neocapritermes opacus and frequently emigrates to new nest sites. During both activities the ants employ chemical trail communication. The trail pheromone orginates from the pygidial gland. Among the substances identified in the pygidial gland secretions, only citronellal was effective as a trail pheromone. Isopulegol elicited an increase in locomotory activity in the ants and may function as a synergist recruitment signal. The chemical signal is enhanced by a shaking display performed by the recruiting ant.
-
communication in the migratory termite hunting ant Pachycondyla termitopone marginata formicidae ponerinae
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 1996Co-Authors: Bert Holldobler, Paulo S. Oliveira, Inara R. Leal, Edelgard Janssen, H J Bestmann, F. Kern, Wilfried A. KönigAbstract:The Neotropical species Pachycondyla marginata conducts well-organized predatory raids on the termite species Neocapritermes opacus and frequently emigrates to new nest sites. During both activities the ants employ chemical trail communication. The trail pheromone orginates from the pygidial gland. Among the substances identified in the pygidial gland secretions, only citronellal was effective as a trail pheromone. Isopulegol elicited an increase in locomotory activity in the ants and may function as a synergist recruitment signal. The chemical signal is enhanced by a shaking display performed by the recruiting ant.
Paulo S. Oliveira - One of the best experts on this subject based on the ideXlab platform.
-
Structural and ultrastructural characterization of the spermatozoa in Pachycondyla striata and P-marginata
Insectes Sociaux, 2016Co-Authors: Livia Cuquetto-leite, Paulo S. Oliveira, Heidi Dolder, N. B. Espírito Santo, J. Lino-neto, K. ManciniAbstract:This study characterizes the male gametic cells in two ant species (Pachycondyla striata and Pachnoda marginata) by light and transmission electron microscopies. The sperm of both species is composed of head, flagellum, and transition regions. The head consists of the acrosome, tapered and bilayer, and a cylindrical nucleus. In P. marginata, the intranuclear material is homogeneously compacted, and in P. striata, there are translucent inclusions and density variations. In the transition region of both species, centriolar adjunct, nuclear base, and the modified basal body (structure of the spermatozoa equivalent to the spermatids’ centriole) coexist and are progressively replaced by two oval and symmetrical mitochondrial derivatives and an axoneme 9 + 9 + 2, respectively, in addition to two symmetrical triangular accessory bodies. Moreover, cytochemical analysis with Ethanolic Phosphotungstic Acid Method (E-PTA) revealed species-specific features not previously reported in the Formicidae, such as the presence of E-PTA negative acrosomal vesicle, E-PTA positive perforatorium, and E-PTA positive nucleus, all in P. marginata. Mitochondrial derivatives exhibited distinct behavior in its internal composition, with E-PTA negative mitochondrial cristae and E-PTA positive paracrystalline in both species. Sperm morphology in Pachycondyla has marked morphological similarities with other ant groups, and its specific features can be useful tools to understand phylogenetic relationships within the Formicidae and Hymenoptera.
-
Seasonal patterns in the orientation system of the migratory ant Pachycondyla marginata
Die Naturwissenschaften, 2001Co-Authors: Daniel Acosta-avalos, Darci M. S. Esquivel, Eliane Wajnberg, Henrique Lins De Barros, Paulo S. Oliveira, Inara R. LealAbstract:Route directions of migrations by the neotropical termite-hunting ant Pachycondyla marginata at a forest reserve in Southeast Brazil were analysed by circular statistic. Colony movement patterns were compared between the rainy/hot and dry/cold seasons. Migrations during the dry/cold season are significantly oriented 13° with the magnetic North–South axis, while rainy/hot migrations do not exhibit a preferred direction. This result is discussed considering the hypothesis that P. marginata ants may use the geomagnetic field as an orientation cue for migrations in the dry/cold season. The presence of magnetic iron oxides in the head and abdomen of P. marginata is consistent with this suggestion.
-
Isolation of magnetic nanoparticles from Pachycondyla marginata ants
The Journal of Experimental Biology, 1999Co-Authors: Daniel Acosta-avalos, Eliane Wajnberg, Paulo S. Oliveira, Inara R. Leal, M. Farina, Darci M. S. EsquivelAbstract:We report on the presence of magnetic iron oxides in the migratory ant Pachycondyla marginata. Magnetic particles were extracted from different parts of the ant (head, thorax and abdomen) using magnetic precipitation methods. Electron spectroscopic images for iron and oxygen were obtained from the extracted particles, and, by using the corresponding electron micrographs, histograms of size distribution were constructed. Selected area diffraction patterns were also obtained from the particles, and analysis of these showed the presence of a mixture of different iron oxides, including the magnetic oxides, magnetite and maghemite. The size distribution of the particles in the abdomen is different from that in the thorax and the head. In accordance with the hypothesis of magnetic orientation based on the presence of magnetic material within the body, two regions of the ant, the head and the abdomen, could be implicated in the detection of the geomagnetic field.
-
Communication in the migratory termite-hunting ant Pachycondyla (= Termitopone) marginata (Formicidae, Ponerinae)
Journal of Comparative Physiology A, 1996Co-Authors: Bert Holldobler, Paulo S. Oliveira, Inara R. Leal, Edelgard Janssen, Hans‐jürgen Bestmann, F. Kern, Wilfried A. KönigAbstract:The Neotropical species Pachycondyla marginata conducts well-organized predatory raids on the termite species Neocapritermes opacus and frequently emigrates to new nest sites. During both activities the ants employ chemical trail communication. The trail pheromone orginates from the pygidial gland. Among the substances identified in the pygidial gland secretions, only citronellal was effective as a trail pheromone. Isopulegol elicited an increase in locomotory activity in the ants and may function as a synergist recruitment signal. The chemical signal is enhanced by a shaking display performed by the recruiting ant.
-
communication in the migratory termite hunting ant Pachycondyla termitopone marginata formicidae ponerinae
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 1996Co-Authors: Bert Holldobler, Paulo S. Oliveira, Inara R. Leal, Edelgard Janssen, H J Bestmann, F. Kern, Wilfried A. KönigAbstract:The Neotropical species Pachycondyla marginata conducts well-organized predatory raids on the termite species Neocapritermes opacus and frequently emigrates to new nest sites. During both activities the ants employ chemical trail communication. The trail pheromone orginates from the pygidial gland. Among the substances identified in the pygidial gland secretions, only citronellal was effective as a trail pheromone. Isopulegol elicited an increase in locomotory activity in the ants and may function as a synergist recruitment signal. The chemical signal is enhanced by a shaking display performed by the recruiting ant.
Patrizia D'ettorre - One of the best experts on this subject based on the ideXlab platform.
-
RSBL-2013-0125-Chemistry
2016Co-Authors: Heikki Helanterä, Oliver Aehle, Maurice Roux, Jürgen Heinze, Patrizia D'ettorreAbstract:GC-MS profiles of Pachycondyla inversa worker
-
RSBL-2013-0125-Behaviour
2016Co-Authors: Heikki Helanterä, Oliver Aehle, Maurice Roux, Jürgen Heinze, Patrizia D'ettorreAbstract:Behavioural profiles of Pachycondyla inversa workers obtained through scan samplin
-
RSBL-2013-0125-Genotypes
2016Co-Authors: Heikki Helanterä, Oliver Aehle, Maurice Roux, Jürgen Heinze, Patrizia D'ettorreAbstract:Genotypes of Pachycondyla inversa workers and queens on 5 microsatellite loc
-
Family-based guilds in the ant Pachycondyla inversa.
Biology letters, 2013Co-Authors: Heikki Helanterä, Oliver Aehle, Maurice Roux, Jürgen Heinze, Patrizia D'ettorreAbstract:High relatedness promotes the evolution of sociality because potentially costly cooperative behaviours are directed towards kin. However, societies, such as those of social insects, also benefit from genetic diversity, e.g. through enhanced disease resistance and division of labour. Effects of genetic diversity have been investigated in a few complex eusocial species. Here, we show that genetically based division of labour may also be important in ‘simple societies’, with fewer individuals and limited morphological caste differentiation. The ponerine ant Pachycondyla inversa has small colonies, headed by several unrelated queens. We show that nest-mate workers from different matrilines engage in different tasks, have distinct chemical profiles and associate preferentially with kin in the nest, while queens and brood stay together. This suggests that genetically based division of labour may precede the evolution of complex eusociality and facilitate the existence of low relatedness societies functioning as associations of distinct families that mutually benefit from group living.
-
Chemical Signature and Reproductive Status in the Facultatively Polygynous ant Pachycondyla Verenae
Journal of chemical ecology, 2012Co-Authors: Sophie E. F. Evison, Patrizia D'ettorre, Ronara Souza Ferreira, Dominique Fresneau, Chantal PoteauxAbstract:In insects, cuticular hydrocarbons (CHCs) generally are used as cues and signals for within colony processes, such as signaling reproductive status, and between colony processes, such as colony membership. We examined CHC profiles of the facultatively polygynous ant Pachycondyla verenae in order to identify chemical signals of reproductive queens within colonies containing many gynes. Colonies of P. verenae, belonging to two different members of a complex of morphospecies, were collected from three geographic localities within South America. We also tested whether CHC profiles differed between geographic localities and morphospecies. We found three alkenes, two isomers of pentacosene and heptacosene, which were more abundant in CHC profiles of reproductive queens of this morphospecies complex. When we tested whether these differences were consistent across geographic localities, we found the abundance of these alkenes differed according to morphospecies, with the isomers of pentacosene being more abundant in queens from morph one, and heptacosene being more abundant in queens from morph two. Our study has given further insight into the mechanisms behind maintenance of reproductive dominance, and has demonstrated that chemical signatures associated with reproductive status in Pachycondyla verenae are not conserved within this species complex.
Jacques H C Delabie - One of the best experts on this subject based on the ideXlab platform.
-
Studies on the Karyotype of the Ant Pachycondyla harpax (Formicidae: Ponerinae: Ponerini) in Southern Bahia, Brazil
Florida Entomologist, 2014Co-Authors: Yamid Arley Mera Velasco, Sebastien Lacau, Jacques H C Delabie, Marco Antonio Costa, Cléa Dos Santos Ferreira MarianoAbstract:Abstract Cytogenetic analyzes were carried out on populations of Pachycondyla harpax (Fabricius, 1804) (Hymenoptera: Formicidae: Ponerini) in southern Bahia, Brazil. The chromosome number was variable with 2n = 90–92, and the chromosomes, predominantly acrocentric, were characterized by being small in size. The karyotype formulas of the studied populations were: Ilheus 2K = 16M + 76A, Una 2K = 16M + 74A and Belmonte 2K = 16M + 76A. The karyotype of a fourth population (Igrapiuna) was undetermined. Fluorochrome banding shows the presence of heterochromatic blocks rich in GC in the pericentromeric region of one of the metacentric pairs, indicating the nucleolus organizer regions. The first case of a diploid male in the genus Pachycondyla is reported.
-
Notes on biology of Brazilian populations of ants of the Pachycondyla foetida species complex (Formicidae: Ponerinae)
Sociobiology, 2013Co-Authors: Itanna Oliveira Fernandes, Marcio Luiz De Oliveira, Jacques H C DelabieAbstract:In ants, biology studies are especially important to complete the information aiming to identify species belonging to unresolved or confused taxa in taxonomy. Such observations allow the inclusion of biological data with other characteristics of determined group, something that preserved specimens in collections do not reveal, such as nesting site, foraging time, nuptial flight and especially the relationship between castes, supporting taxonomic analysis and descriptions. Here, nests of three species of the complex foetida of the genus Pachycondyla were observed and collected in three Brazilian localities. Pleometrosis, secondary monogyny and cannibalism were observed for the ant P. inversa . In many ant species, queens newly mated are associated with other queens to establish new colonies, independent of parenthood. In the ant genus Pachycondyla , the reproductive structure varies broadly and aggressiveness seems to be an important factor in structuring the organization and reproductive division in the colony. The occurrence of males in nests of P. inversa and P. curvinodis allowed the description of males. The nuptial flight period was estimated to of P. inversa (August), P. villosa (October) and P. curvinodis (November).
-
Contribution of Cytogenetics to the Debate on the Paraphyly of Pachycondyla spp. (Hymenoptera, Formicidae, Ponerinae)
Psyche: A Journal of Entomology, 2012Co-Authors: Cléa Dos Santos Ferreira Mariano, Silvia Das Gracas Pompolo, Janisete G. Silva, Jacques H C DelabieAbstract:We present evidence of the paraphyly of the ant genus Pachycondyla resulting from our cytogenetic studies on 29 populations in 18 species from Brazil and French Guyana. It is likely that karyotypes with a large number of chromosomes and comprising mostly small acrocentric chromosomes in species within the Pachycondyla stricto sensu group resulted from a succession of centric fission events. On the other hand, karyotypes with a small chromosome number comprising mostly metacentric chromosomes are also interpreted as little derived and tend to undergo centric fission. The karyotypes of the group Neoponera are more heterogeneous and probably undergo successive cycles of rearrangements tending to increase the chromosome number by centric fission. The apicalis and verenae complexes form two probable sister groups that evolved independently due to centric fissions (verenae) and pericentric inversions (apicalis). Our results reveal the karyotype diversity in the genus and reinforce the hypothesis on the paraphyly of Pachycondyla.
-
questions sur la monophylie du taxon Pachycondyla smith 1858 approche cytogenetique sur le sous genre Pachycondyla sensu emery 1901 hymenoptera formicidae ponerinae
Bulletin de la Société entomologique de France, 2006Co-Authors: Clea S F Mariano, Silvia Das Gracas Pompolo, Sebastien Lacau, Jacques H C DelabieAbstract:Les chromosomes metaphasiques de trois especes de Fourmis neotropicales du genre Pachycondyla (Formicidae : Ponerinae) sont etudies pour la premiere fois. Toutes trois possedent un nombre singulierement eleve de chromosomes, tous extremement petits. Cette caracteristique est convergente avec ce qui est connu d'etudes similaires realisees sur des especes indo-australiennes de Pachycondyla appartenant a l'ancien genre Bothroponera. Nos donnees suggerent que les especes neotropicales terricoles de Pachycondyla (Pachycondyla) sensu Emery, 1901, qui possedent un grand nombre de chromosomes de petite taille et majoritairement acrocentriques, representent une lignee evolutive independante des autres fourmis du genre.
-
A multidisciplinary approach to discriminating different taxa in the species complex Pachycondyla villosa (Formicidae)
Biological Journal of the Linnean Society, 2002Co-Authors: Christophe Lucas, Jacques H C Delabie, Jürgen Heinze, Dominique Fresneau, Kerstin Kolmer, Dang B. PhoAbstract:A multidisciplinary approach provides new evidence that strongly supports the differentiation of three taxa previously confounded in a single species, Pachycondyla villosa. All specimens studied were collected in the same location at Ilheus, Bahia, Brazil. Bivariate plots of petiole heights vs. petiole lengths and isozyme patterns clearly differentiate the three taxa. Chain lengths and chemical structures of cuticular hydrocarbons are characteristic of each taxon. This congruent evidence shows that there are three different valid species. Ecological hypotheses are discussed to explain the benefits of these species remaining sympatric. © 2002 The Linnean Society of London, Biological Journal of the Linnean Society, 2002, 75, 249–259.
