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Peter Jacklyn - One of the best experts on this subject based on the ideXlab platform.
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Isolated in an ocean of grass: low levels of gene flow between termite subpopulations
Molecular Ecology, 2013Co-Authors: Anna M. Schmidt, Peter Jacklyn, Judith KorbAbstract:: Habitat fragmentation is one of the most important causes of biodiversity loss, but many species are distributed in naturally patchy habitats. Such species are often organized in highly dynamic metapopulations or in patchy populations with high gene flow between subpopulations. Yet, there are also species that exist in stable patchy habitats with small subpopulations and presumably low dispersal rates. Here, we present population genetic data for the 'magnetic' termite Amitermes meridionalis, which show that short distances between subpopulations do not hinder exceptionally strong genetic differentiation (FST : 0.339; RST : 0.636). Despite the strong genetic differentiation between subpopulations, we did not find evidence for genetic impoverishment. We propose that loss of genetic diversity might be counteracted by a long colony life with low colony turnover. Indeed, we found evidence for the inheritance of colonies by so-called 'replacement reproductives'. Inhabiting a mound for several generations might result in loss of gene diversity within a colony but maintenance of gene diversity at the subpopulation level.
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phylogeography of an australian termite Amitermes laurensis isoptera termitidae with special reference to the variety of mound shapes
Molecular Phylogenetics and Evolution, 2007Co-Authors: Masato Ozeki, Peter Jacklyn, Yuji Isagi, Hiromi Tsubota, David M J S BowmanAbstract:In northern Australia, the debris-feeding termite Amitermes laurensis builds tall, wedge-shaped mounds in the northern part of Cape York Peninsula and Arnhem Land, where their habitats are seasonally flooded, and small dome shaped mounds in the southeastern part of Cape York Peninsula, where their habitats are well-drained. Phylogeographic analyses were conducted in 238 individuals from 30 populations using the mitochondrial cytochrome oxidase II (COII) gene. DNA sequences of 50 haplotypes were used to construct NJ, MP and ML trees. Phylogenetic trees for 16 Amitermes species showed monophyly of A. laurensis and the variation of A. laurensis mounds did not strongly correspond to the intraspecific phylogeny. It was observed that mounds with the same shape were constructed by phylogenetically different groups under similar environmental conditions and different mounds shapes were built by phylogenetically closely related groups under the different environmental conditions. Thus, phylogenetically close groups of A. laurensis, in different habitats, may adapt to environmental conditions by constructing different mound shapes. We also investigated the phylogeographic structure of A. laurensis. The significant positive correlation between genetic and geographic distances indicated isolation by distance, reflecting restricted dispersal ability of alates. Although the overall genetic structure of A. laurensis showed isolation by distance, we also identified two exceptions: (i) secondary contacts of genetically divergent lineages in southern Cape York Peninsula, and (ii) low genetic differences between geographically separated populations of Cape York Peninsula and Arnhem Land. Therefore, the phylogeography of A. laurensis may reflect continuous gene flow restricted to short distances and past changes of gene flow associated with the fluctuation of environmental conditions accompanying the changing sea levels in the Quaternary.
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evidence for the use of magnetic cues in mound construction by the termite Amitermes meridionalis isoptera termitinae
Australian Journal of Zoology, 2002Co-Authors: Peter Jacklyn, Ursula MunroAbstract:The termite Amitermes meridionalis builds meridionally elongated mounds. We removed the tops of such mounds and then allowed the termites to repair their mounds in the natural geomagnetic field and in artificial magnetic fields with different magnetic declinations. Cross-sections of repaired mounds were taken and the arrangement of the small, elongated cells that form the basis of mound architecture was assessed. The results suggest that the termites align mound cells along the existing axis of the mound and the cardinal axes of the horizontal component of the applied magnetic field.
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evidence for adaptive variation in the orientation of Amitermes isoptera termitinae mounds from northern australia
Australian Journal of Zoology, 1991Co-Authors: Peter JacklynAbstract:Amitermes meridionalis and Amitermes laurensis construct meridional termite mounds that are endemic to northern Australia. The first comprehensive survey of the orientation of these mounds, involving 68 mound sites across northern Australia, is described. The mean mound orientations of most coastal A. meridonalis sites were significantly (P < 0.05) to the west of those of most inland A. meridionalis sites. The mean orientations of most A. laurensis sites in Cape York Peninsula were significantly (P < 0.05) to the west of those of most A. meridonalis and A. laurensis sites in the Northern Territory. Most shaded mound sites had significantly (P < 0.05) greater variance in mound orientation than nearby open sites. It is suggested that the geographic variation in mound orientation is an adaptive response to differences in local environmental conditions and that such variation provides the key to explaining the adaptive value of meridional orientation.
Rudolf H Scheffrahn - One of the best experts on this subject based on the ideXlab platform.
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comparative metagenomic and metatranscriptomic analysis of hindgut paunch microbiota in wood and dung feeding higher termites
PLOS ONE, 2013Co-Authors: Rudolf H Scheffrahn, Shaomei He, Natalia Ivanova, Edward Kirton, Martin Allgaier, Claudia Bergin, Nikos C KyrpidesAbstract:Termites effectively feed on many types of lignocellulose assisted by their gut microbial symbionts. To better understand the microbial decomposition of biomass with varied chemical profiles, it is important to determine whether termites harbor different microbial symbionts with specialized functionalities geared toward different feeding regimens. In this study, we compared the microbiota in the hindgut paunch of Amitermes wheeleri collected from cow dung and Nasutitermes corniger feeding on sound wood by 16S rRNA pyrotag, comparative metagenomic and metatranscriptomic analyses. We found that Firmicutes and Spirochaetes were the most abundant phyla in A. wheeleri, in contrast to N. corniger where Spirochaetes and Fibrobacteres dominated. Despite this community divergence, a convergence was observed for functions essential to termite biology including hydrolytic enzymes, homoacetogenesis and cell motility and chemotaxis. Overrepresented functions in A. wheeleri relative to N. corniger microbiota included hemicellulose breakdown and fixed-nitrogen utilization. By contrast, glycoside hydrolases attacking celluloses and nitrogen fixation genes were overrepresented in N. corniger microbiota. These observations are consistent with dietary differences in carbohydrate composition and nutrient contents, but may also reflect the phylogenetic difference between the hosts.
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a new termite species isoptera termitidae termitinae Amitermes and first record of a subterranean termite from the coastal desert of south america
Zootaxa, 2010Co-Authors: Rudolf H Scheffrahn, Jeanbernard HuchetAbstract:At about one hundred species, Amitermes, is the second largest genus after Microcerotermes in the subfamily Termitinae. This cosmopolitan genus is found in a wide variety of habitats from rainforests e.g., Amitermes excellens (Silvestri) from Guyana and Amitermes dentatus (Haviland) from Sumatra to deserts, e.g. Amitermes emersoni Light from Coachella, California and Amitermes desertorum Desneux from Egypt. Only eight species of Amitermes are known from the Neotropics and only five occur across mainland South America. Soldiers of Amitermes are characterized by a bulbous head capsule and sickle-shaped mandibles, each with a single tooth of various shapes on their inner margins. Soldiers of all species have a large cephalic gland opening to a circular fontanelle on the frons. When confronted by an agonist, the soldier emits a terpenoid secretion which oozes onto setae around and below the fontanelle. Herein, is described a new Amitermes from Peru and the first record of a subterranean termite along the Pacific coastal desert of South America.
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Amitermes amicki a new subterranean termite isoptera termitidae termitinae from aruba
Florida Entomologist, 1999Co-Authors: Rudolf H Scheffrahn, Nanyao Su, Timothy G MylesAbstract:Amitermes amicki n. sp. is described from soldiers collected on Aruba. For comparison, the soldier of A. beaumonti is redescribed from specimens collected in Mexico, Belize, and Cuba. Amitermes amicki is the eighth congener thus far described from the Neotropical Region. A technique is reported to enhance the visual clarity of digitized scanning electron micrographs.
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Keys to Soldier and Winged Adult Termites (Isoptera) of Florida
Florida Entomologist, 1994Co-Authors: Rudolf H Scheffrahn, Nanyao SuAbstract:Illustrated identification keys are presented for soldiers and winged adults of the following 17 termite species known from Florida: Calcaritermes nearcticus Snyder, Neotermes castaneus (Burmeister), N. jouteli (Banks), N. luykxi Nickle and Collins, Kalotermes approximatus Snyder, Incisitermes milleri (Emerson), I. minor (Hagen), I. schwarzi (Banks), I. snyderi (Light), Cryptotermes brevis (Walker), and C. cavifrons Banks, Family Kalotermitidae; Coptotermes formosanus Shiraki, Reticulitermes flavipes (Kollar), R. hageni Banks, R. virginicus (Banks), and Prorhinotermes simplex (Hagen), Family Rhinotermitidae; and Amitermes floridensis Scheffrahn, Mangold, & Su, Family Termitidae.
David M J S Bowman - One of the best experts on this subject based on the ideXlab platform.
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phylogeography of an australian termite Amitermes laurensis isoptera termitidae with special reference to the variety of mound shapes
Molecular Phylogenetics and Evolution, 2007Co-Authors: Masato Ozeki, Peter Jacklyn, Yuji Isagi, Hiromi Tsubota, David M J S BowmanAbstract:In northern Australia, the debris-feeding termite Amitermes laurensis builds tall, wedge-shaped mounds in the northern part of Cape York Peninsula and Arnhem Land, where their habitats are seasonally flooded, and small dome shaped mounds in the southeastern part of Cape York Peninsula, where their habitats are well-drained. Phylogeographic analyses were conducted in 238 individuals from 30 populations using the mitochondrial cytochrome oxidase II (COII) gene. DNA sequences of 50 haplotypes were used to construct NJ, MP and ML trees. Phylogenetic trees for 16 Amitermes species showed monophyly of A. laurensis and the variation of A. laurensis mounds did not strongly correspond to the intraspecific phylogeny. It was observed that mounds with the same shape were constructed by phylogenetically different groups under similar environmental conditions and different mounds shapes were built by phylogenetically closely related groups under the different environmental conditions. Thus, phylogenetically close groups of A. laurensis, in different habitats, may adapt to environmental conditions by constructing different mound shapes. We also investigated the phylogeographic structure of A. laurensis. The significant positive correlation between genetic and geographic distances indicated isolation by distance, reflecting restricted dispersal ability of alates. Although the overall genetic structure of A. laurensis showed isolation by distance, we also identified two exceptions: (i) secondary contacts of genetically divergent lineages in southern Cape York Peninsula, and (ii) low genetic differences between geographically separated populations of Cape York Peninsula and Arnhem Land. Therefore, the phylogeography of A. laurensis may reflect continuous gene flow restricted to short distances and past changes of gene flow associated with the fluctuation of environmental conditions accompanying the changing sea levels in the Quaternary.
Judith Korb - One of the best experts on this subject based on the ideXlab platform.
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Isolated in an ocean of grass: low levels of gene flow between termite subpopulations
Molecular Ecology, 2013Co-Authors: Anna M. Schmidt, Peter Jacklyn, Judith KorbAbstract:: Habitat fragmentation is one of the most important causes of biodiversity loss, but many species are distributed in naturally patchy habitats. Such species are often organized in highly dynamic metapopulations or in patchy populations with high gene flow between subpopulations. Yet, there are also species that exist in stable patchy habitats with small subpopulations and presumably low dispersal rates. Here, we present population genetic data for the 'magnetic' termite Amitermes meridionalis, which show that short distances between subpopulations do not hinder exceptionally strong genetic differentiation (FST : 0.339; RST : 0.636). Despite the strong genetic differentiation between subpopulations, we did not find evidence for genetic impoverishment. We propose that loss of genetic diversity might be counteracted by a long colony life with low colony turnover. Indeed, we found evidence for the inheritance of colonies by so-called 'replacement reproductives'. Inhabiting a mound for several generations might result in loss of gene diversity within a colony but maintenance of gene diversity at the subpopulation level.
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isolation and characterization of 10 microsatellite loci in the magnetic termite Amitermes meridionalis isoptera termitidae
Molecular Ecology Notes, 2007Co-Authors: A M Schmidt, A Trindl, Judith KorbAbstract:The elongated mounds of the ‘magnetic termite’, Amitermes meridionalis are a prominent feature of the Northern Territory in Australia. They are restricted to habitat patches of seasonally flooded plains which are largely isolated from each other. To investigate the population structure of A. meridionalis, we developed 10 polymorphic microsatellite loci. We tested the variability of the markers on at least 20 individuals from two populations. We found three to 12 alleles per locus with a level of heterozygosity at each locus ranging from 0.05 to 0.74.
A M Schmidt - One of the best experts on this subject based on the ideXlab platform.
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‘Magnetic’ termite mounds: is their unique shape an adaptation to facilitate gas exchange and improve food storage?
Insectes Sociaux, 2014Co-Authors: A M Schmidt, P. Jacklyn, J. KorbAbstract:Social insects can build impressive nest mounds but the functional significance of their architecture is rarely studied in experiments. The ‘magnetic’ termite mounds of monsoonal northern Australia built by Amitermes meridionalis are notable for their elongated wedge shape and north–south axial orientation. We tested whether the shape is an adaptation to facilitate gas exchange and the preservation of food stores by two experimental manipulations of mounds in situ covering all seasons. First, mounds were shaded to limit drying after rain and second, mound shape was amended from wedge to (approximate) sphere. Food storage, fungal contamination, and internal CO_2 concentration were unaffected by manipulation, but showed a distinct seasonal dynamic, with storage peaking towards the onset of rains and fungal load towards the end of the rainy season. Internal CO_2 concentrations were subject to a diurnal cycle, but also showed elevation during rains. We propose that one advantage of the wedge shape is the efficient use of building effort to achieve good passive ventilation for the food storage areas.
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isolation and characterization of 10 microsatellite loci in the magnetic termite Amitermes meridionalis isoptera termitidae
Molecular Ecology Notes, 2007Co-Authors: A M Schmidt, A Trindl, Judith KorbAbstract:The elongated mounds of the ‘magnetic termite’, Amitermes meridionalis are a prominent feature of the Northern Territory in Australia. They are restricted to habitat patches of seasonally flooded plains which are largely isolated from each other. To investigate the population structure of A. meridionalis, we developed 10 polymorphic microsatellite loci. We tested the variability of the markers on at least 20 individuals from two populations. We found three to 12 alleles per locus with a level of heterozygosity at each locus ranging from 0.05 to 0.74.
