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Greta J. Binford - One of the best experts on this subject based on the ideXlab platform.
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Global biogeography of Tetragnatha spiders reveals multiple colonization of the Caribbean
2018Co-Authors: Klemen Candek, Greta J. Binford, Ingi Agnarsson, Matjaz KuntnerAbstract:Organismal variation in dispersal ability can directly affect levels of gene flow amongst populations, therefore importantly shaping species distributions and species richness patterns. The intermediate dispersal model of biogeography (IDM) predicts that in island systems, species diversity of those lineages with an intermediate dispersal potential is the highest. We broadly test this prediction, focusing on "four-jawed spiders" (genus Tetragnatha) of the Caribbean archipelago. First, we report on original sampling of this globally distributed genus with numerous widespread as well as endemic species. We then reconstruct multiple Tetragnatha phylogenies from roughly 300 individuals delineated into 54 putative species. Our results support the monophyly of the four-jawed spiders but reject the monophyly of those lineages that reach the Caribbean, where we find low levels of endemism yet high diversity within Tetragnatha. The chronogram detects a potential early overwater colonization of the Caribbean, and in combination with reconstructed biogeographic history, refutes the possibility of ancient vicariant origins of Caribbean Tetragnatha as well as the GAARlandia land-bridge scenario. Instead, biogeographic results hypothesize multiple colonization events to, and from the Caribbean since mid-Eocene to late-Miocene. Tetragnatha seems unique among the arachnids explored so far in comprising some species that are excellent dispersers, and others that are not, perhaps having secondarily lost this dispersal propensity. A direct test of the IDM would require consideration of three categories of dispersers. However, four-jawed spiders do not fit one of these three a priori definitions, but rather represent a more complex combination of attributes of a "dynamic disperser".
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Sexually dimorphic venom proteins in long-jawed orb-weaving spiders (Tetragnatha) comprise novel gene families.
PeerJ, 2018Co-Authors: Pamela A. Zobel-thropp, Rosemary G. Gillespie, Greta J. Binford, Emily A. Bulger, Matthew H. J. Cordes, Michael S. BrewerAbstract:Venom has been associated with the ecological success of many groups of organisms, most notably reptiles, gastropods, and arachnids. In some cases, diversification has been directly linked to tailoring of venoms for dietary specialization. Spiders in particular are known for their diverse venoms and wide range of predatory behaviors, although there is much to learn about scales of variation in venom composition and function. The current study focuses on venom characteristics in different sexes within a species of spider. We chose the genus Tetragnatha (Tetragnathidae) because of its unusual courtship behavior involving interlocking of the venom delivering chelicerae (i.e., the jaws), and several species in the genus are already known to have sexually dimorphic venoms. Here, we use transcriptome and proteome analyses to identify venom components that are dimorphic in Tetragnatha versicolor. We present cDNA sequences including unique, male-specific high molecular weight proteins that have remote, if any, detectable similarity to known venom components in spiders or other venomous lineages and have no detectable homologs in existing databases. While the function of these proteins is not known, their presence in association with the cheliceral locking mechanism during mating together with the presence of prolonged male-male mating attempts in a related, cheliceral-locking species (Doryonychus raptor) lacking the dimorphism suggests potential for a role in sexual communication.
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Sexually dimorphic venom proteins in long-jawed orb-weaving spiders (Tetragnatha) with potential roles in sexual interactions
2017Co-Authors: Pamela A. Zobel-thropp, Rosemary G. Gillespie, Greta J. Binford, Emily A. Bulger, Matthew H. J. Cordes, Michael S. BrewerAbstract:Venom has been associated with the ecological success of many groups of organisms, most notably reptiles, gastropods, and arachnids. In some cases, diversification has been directly linked to tailoring of venoms for dietary specialization. Spiders in particular are known for their diverse venoms and wide range of predatory behaviors, although there is much to learn about scales of variation in venom composition and function. The current study focuses on venom characteristics in different sexes within a species of spider. We chose the genus Tetragnatha (Tetragnathidae) because of its unusual courtship behavior involving interlocking of the venom delivering chelicerae (i.e., the jaws), and several species in the genus are already known to have sexually dimorphic venoms. Here, we use transcriptome and proteome analyses to identify venom components that are dimorphic in Tetragnatha versicolor. We present cDNA sequences of unique high molecular weight proteins that are only present in males and that have remote, if any, detectable similarity to known venom components in spiders or other venomous lineages and several have no detectable homologs in existing databases. While the function of these proteins is not known, their presence in association with the cheliceral locking mechanism during mating together with the presence of prolonged male-male mating attempts in a related, cheliceral-locking species (Doryonychus raptor) lacking the dimorphism suggests potential for a role in sexual communication.
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Sexual dimorphism in venom chemistry in Tetragnatha spiders is not easily explained by adult niche differences
Toxicon : official journal of the International Society on Toxinology, 2016Co-Authors: Greta J. Binford, Rosemary G. Gillespie, Wayne P. MaddisonAbstract:Spider venom composition typically differs between sexes. This pattern is anecdotally thought to reflect differences in adult feeding biology. We used a phylogenetic approach to compare intersexual venom dimorphism between species that differ in adult niche dimorphism. Male and female venoms were compared within and between related species of Hawaiian Tetragnatha, a mainland congener, and outgroups. In some species of Hawaiian Tetragnatha adult females spin orb-webs and adult males capture prey while wandering, while in other species both males and females capture prey by wandering. We predicted that, if venom sexual dimorphism is primarily explained by differences in adult feeding biology, species in which both sexes forage by wandering would have monomorphic venoms or venoms with reduced dimorphism relative to species with different adult feeding biology. However, we found striking sexual dimorphism in venoms of both wandering and orb-weaving Tetragnatha species with males having high molecular weight components in their venoms that were absent in females, and a reduced concentration of low molecular weight components relative to females. Intersexual differences in venom composition within Tetragnatha were significantly larger than in non-Tetragnatha species. Diet composition was not different between sexes. This striking venom dimorphism is not easily explained by differences in feeding ecology or behavior. Rather, we hypothesize that the dimorphism reflects male-specific components that play a role in mating biology possibly in sexual stimulation, nuptial gifts and/or mate recognition.
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Resource use within a community of Hawaiian spiders (Araneae: Tetragnathidae)
Annales Zoologici Fennici, 2003Co-Authors: Todd A. Blackledge, Greta J. Binford, Rosemary G. GillespieAbstract:We examined the relationship between web architecture, microhabitat utilization, and prey capture for five sympatric species of spiders (Araneae: Tetragnathidae: Tetragnatha Latreille) in Waikamoi Preserve, East Maui, Hawaiian Islands. We found that each species of spider built webs that differed from its congeners in one or more architectural and microhabitat features, and that each species also differed in the types of insect prey they captured. Although the causal mechanisms remain to be tested, we suggest that species-specific differences in web building behaviors could account for the differences found in utilization of prey and microhabitat resources. Furthermore, the ability to construct webs with different architectures may be related to the extraordinary diversification of endemic web-building Hawaiian Tetragnatha.
Rosemary G. Gillespie - One of the best experts on this subject based on the ideXlab platform.
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Niche conservatism predominates in adaptive radiation: comparing the diversification of Hawaiian arthropods using ecological niche modelling
Biological Journal of the Linnean Society, 2019Co-Authors: Anna E. Hiller, Michelle S. Koo, Kari Roesch Goodman, Kerry L. Shaw, Patrick M. O’grady, Rosemary G. GillespieAbstract:Abstract The role of the environmental niche in fostering ecological divergence during adaptive radiation remains enigmatic. In this study, we examine the interplay between environmental niche divergence and conservatism in the context of adaptive radiation on oceanic islands, by characterizing the niche breadth of four Hawaiian arthropod radiations: Tetragnatha spiders (Tetragnathidae Latreille, 1804), Laupala crickets (Gryllidae Otte, 1994), a clade of Drosophila flies (Drosophilidae Fallén, 1823) and Nesosydne planthoppers (Delphacidae Kirkaldy, 1907). We assembled occurrence datasets for the four lineages, modelled their distributions and quantified niche overlap. All four groups occupy the islands in distinct ways, highlighting the contrasting axes of diversification for different lineages. Laupala and Nesosydne have opposite environmental niche extents (broad and narrow, respectively), whereas Tetragnatha and Drosophila share relatively intermediate tolerances. Temperature constrains the distributions of all four radiations. Tests of phylogenetic signal suggest that, for Tetragnatha and Drosophila, closely related species exhibit similar environmental niches; thus, diversification is associated with niche conservatism. Sister species comparisons also show that populations often retain similar environmental tolerances, although exceptions do occur. Results imply that diversification does not occur through ecological speciation; instead, adaptive radiation occurs largely within a single environment.
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Sexually dimorphic venom proteins in long-jawed orb-weaving spiders (Tetragnatha) comprise novel gene families.
PeerJ, 2018Co-Authors: Pamela A. Zobel-thropp, Rosemary G. Gillespie, Greta J. Binford, Emily A. Bulger, Matthew H. J. Cordes, Michael S. BrewerAbstract:Venom has been associated with the ecological success of many groups of organisms, most notably reptiles, gastropods, and arachnids. In some cases, diversification has been directly linked to tailoring of venoms for dietary specialization. Spiders in particular are known for their diverse venoms and wide range of predatory behaviors, although there is much to learn about scales of variation in venom composition and function. The current study focuses on venom characteristics in different sexes within a species of spider. We chose the genus Tetragnatha (Tetragnathidae) because of its unusual courtship behavior involving interlocking of the venom delivering chelicerae (i.e., the jaws), and several species in the genus are already known to have sexually dimorphic venoms. Here, we use transcriptome and proteome analyses to identify venom components that are dimorphic in Tetragnatha versicolor. We present cDNA sequences including unique, male-specific high molecular weight proteins that have remote, if any, detectable similarity to known venom components in spiders or other venomous lineages and have no detectable homologs in existing databases. While the function of these proteins is not known, their presence in association with the cheliceral locking mechanism during mating together with the presence of prolonged male-male mating attempts in a related, cheliceral-locking species (Doryonychus raptor) lacking the dimorphism suggests potential for a role in sexual communication.
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Ancient DNA Resolves the History of Tetragnatha (Araneae, Tetragnathidae) Spiders on Rapa Nui.
Genes, 2017Co-Authors: Darko D. Cotoras, Rosemary G. Gillespie, Gemma G. R. Murray, Joshua D. Kapp, Charles E. Griswold, W. Brian Simison, Richard E. Green, Beth ShapiroAbstract:Rapa Nui is one of the most remote islands in the world. As a young island, its biota is a consequence of both natural dispersals over the last ~1 million years and recent human introductions. It therefore provides an opportunity to study a unique community assemblage. Here, we extract DNA from museum-preserved and newly field-collected spiders from the genus Tetragnatha to explore their history on Rapa Nui. Using an optimized protocol to recover ancient DNA from museum-preserved spiders, we sequence and assemble partial mitochondrial genomes from nine Tetragnatha species, two of which were found on Rapa Nui, and estimate the evolutionary relationships between these and other Tetragnatha species. Our phylogeny shows that the two Rapa Nui species are not closely related. One, the possibly extinct, T. paschae, is nested within a circumtropical species complex (T. nitens), and the other (Tetragnatha sp. Rapa Nui) appears to be a recent human introduction. Our results highlight the power of ancient DNA approaches in identifying cryptic and rare species, which can contribute to our understanding of the global distribution of biodiversity in all taxonomic lineages.
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Sexually dimorphic venom proteins in long-jawed orb-weaving spiders (Tetragnatha) with potential roles in sexual interactions
2017Co-Authors: Pamela A. Zobel-thropp, Rosemary G. Gillespie, Greta J. Binford, Emily A. Bulger, Matthew H. J. Cordes, Michael S. BrewerAbstract:Venom has been associated with the ecological success of many groups of organisms, most notably reptiles, gastropods, and arachnids. In some cases, diversification has been directly linked to tailoring of venoms for dietary specialization. Spiders in particular are known for their diverse venoms and wide range of predatory behaviors, although there is much to learn about scales of variation in venom composition and function. The current study focuses on venom characteristics in different sexes within a species of spider. We chose the genus Tetragnatha (Tetragnathidae) because of its unusual courtship behavior involving interlocking of the venom delivering chelicerae (i.e., the jaws), and several species in the genus are already known to have sexually dimorphic venoms. Here, we use transcriptome and proteome analyses to identify venom components that are dimorphic in Tetragnatha versicolor. We present cDNA sequences of unique high molecular weight proteins that are only present in males and that have remote, if any, detectable similarity to known venom components in spiders or other venomous lineages and several have no detectable homologs in existing databases. While the function of these proteins is not known, their presence in association with the cheliceral locking mechanism during mating together with the presence of prolonged male-male mating attempts in a related, cheliceral-locking species (Doryonychus raptor) lacking the dimorphism suggests potential for a role in sexual communication.
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Sexual dimorphism in venom chemistry in Tetragnatha spiders is not easily explained by adult niche differences
Toxicon : official journal of the International Society on Toxinology, 2016Co-Authors: Greta J. Binford, Rosemary G. Gillespie, Wayne P. MaddisonAbstract:Spider venom composition typically differs between sexes. This pattern is anecdotally thought to reflect differences in adult feeding biology. We used a phylogenetic approach to compare intersexual venom dimorphism between species that differ in adult niche dimorphism. Male and female venoms were compared within and between related species of Hawaiian Tetragnatha, a mainland congener, and outgroups. In some species of Hawaiian Tetragnatha adult females spin orb-webs and adult males capture prey while wandering, while in other species both males and females capture prey by wandering. We predicted that, if venom sexual dimorphism is primarily explained by differences in adult feeding biology, species in which both sexes forage by wandering would have monomorphic venoms or venoms with reduced dimorphism relative to species with different adult feeding biology. However, we found striking sexual dimorphism in venoms of both wandering and orb-weaving Tetragnatha species with males having high molecular weight components in their venoms that were absent in females, and a reduced concentration of low molecular weight components relative to females. Intersexual differences in venom composition within Tetragnatha were significantly larger than in non-Tetragnatha species. Diet composition was not different between sexes. This striking venom dimorphism is not easily explained by differences in feeding ecology or behavior. Rather, we hypothesize that the dimorphism reflects male-specific components that play a role in mating biology possibly in sexual stimulation, nuptial gifts and/or mate recognition.
Joo-pil Kim - One of the best experts on this subject based on the ideXlab platform.
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Predation Efficiency of the Spider Tetragnatha squamata(Araneae: Tetragnathidae) to Tea Leat\fhopper Empoasca vitis (Insecta: Homoptera)
Animal Systematics Evolution and Diversity, 1998Co-Authors: Heng-mai Yan, Man-yuan Liu, Joo-pil KimAbstract:The spider, Tetragnatha squamata and its prey Empoasca vitis, the tea leafhopper, were investigated in laboratory on the prey-predator relationship. The predator spider showed a significant response to the increase of the prey. The predation effiency and the response of predator to its density were examined as well. The result of the experiments are give as questions.
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predation efficiency of the spider Tetragnatha squamata araneae tetragnathidae to tea leat fhopper empoasca vitis insecta homoptera
Animal Systematics Evolution and Diversity, 1998Co-Authors: Heng-mai Yan, Man-yuan Liu, Joo-pil KimAbstract:The spider, Tetragnatha squamata and its prey Empoasca vitis, the tea leafhopper, were investigated in laboratory on the prey-predator relationship. The predator spider showed a significant response to the increase of the prey. The predation effiency and the response of predator to its density were examined as well. The result of the experiments are give as questions.
Michael S. Brewer - One of the best experts on this subject based on the ideXlab platform.
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Sexually dimorphic venom proteins in long-jawed orb-weaving spiders (Tetragnatha) comprise novel gene families.
PeerJ, 2018Co-Authors: Pamela A. Zobel-thropp, Rosemary G. Gillespie, Greta J. Binford, Emily A. Bulger, Matthew H. J. Cordes, Michael S. BrewerAbstract:Venom has been associated with the ecological success of many groups of organisms, most notably reptiles, gastropods, and arachnids. In some cases, diversification has been directly linked to tailoring of venoms for dietary specialization. Spiders in particular are known for their diverse venoms and wide range of predatory behaviors, although there is much to learn about scales of variation in venom composition and function. The current study focuses on venom characteristics in different sexes within a species of spider. We chose the genus Tetragnatha (Tetragnathidae) because of its unusual courtship behavior involving interlocking of the venom delivering chelicerae (i.e., the jaws), and several species in the genus are already known to have sexually dimorphic venoms. Here, we use transcriptome and proteome analyses to identify venom components that are dimorphic in Tetragnatha versicolor. We present cDNA sequences including unique, male-specific high molecular weight proteins that have remote, if any, detectable similarity to known venom components in spiders or other venomous lineages and have no detectable homologs in existing databases. While the function of these proteins is not known, their presence in association with the cheliceral locking mechanism during mating together with the presence of prolonged male-male mating attempts in a related, cheliceral-locking species (Doryonychus raptor) lacking the dimorphism suggests potential for a role in sexual communication.
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Sexually dimorphic venom proteins in long-jawed orb-weaving spiders (Tetragnatha) with potential roles in sexual interactions
2017Co-Authors: Pamela A. Zobel-thropp, Rosemary G. Gillespie, Greta J. Binford, Emily A. Bulger, Matthew H. J. Cordes, Michael S. BrewerAbstract:Venom has been associated with the ecological success of many groups of organisms, most notably reptiles, gastropods, and arachnids. In some cases, diversification has been directly linked to tailoring of venoms for dietary specialization. Spiders in particular are known for their diverse venoms and wide range of predatory behaviors, although there is much to learn about scales of variation in venom composition and function. The current study focuses on venom characteristics in different sexes within a species of spider. We chose the genus Tetragnatha (Tetragnathidae) because of its unusual courtship behavior involving interlocking of the venom delivering chelicerae (i.e., the jaws), and several species in the genus are already known to have sexually dimorphic venoms. Here, we use transcriptome and proteome analyses to identify venom components that are dimorphic in Tetragnatha versicolor. We present cDNA sequences of unique high molecular weight proteins that are only present in males and that have remote, if any, detectable similarity to known venom components in spiders or other venomous lineages and several have no detectable homologs in existing databases. While the function of these proteins is not known, their presence in association with the cheliceral locking mechanism during mating together with the presence of prolonged male-male mating attempts in a related, cheliceral-locking species (Doryonychus raptor) lacking the dimorphism suggests potential for a role in sexual communication.
Heng-mai Yan - One of the best experts on this subject based on the ideXlab platform.
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Predation Efficiency of the Spider Tetragnatha squamata(Araneae: Tetragnathidae) to Tea Leat\fhopper Empoasca vitis (Insecta: Homoptera)
Animal Systematics Evolution and Diversity, 1998Co-Authors: Heng-mai Yan, Man-yuan Liu, Joo-pil KimAbstract:The spider, Tetragnatha squamata and its prey Empoasca vitis, the tea leafhopper, were investigated in laboratory on the prey-predator relationship. The predator spider showed a significant response to the increase of the prey. The predation effiency and the response of predator to its density were examined as well. The result of the experiments are give as questions.
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predation efficiency of the spider Tetragnatha squamata araneae tetragnathidae to tea leat fhopper empoasca vitis insecta homoptera
Animal Systematics Evolution and Diversity, 1998Co-Authors: Heng-mai Yan, Man-yuan Liu, Joo-pil KimAbstract:The spider, Tetragnatha squamata and its prey Empoasca vitis, the tea leafhopper, were investigated in laboratory on the prey-predator relationship. The predator spider showed a significant response to the increase of the prey. The predation effiency and the response of predator to its density were examined as well. The result of the experiments are give as questions.