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Brian M Wiegmann - One of the best experts on this subject based on the ideXlab platform.
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phylogenetics and temporal diversification of the earliest true flies insecta Diptera based on multiple nuclear genes
Systematic Entomology, 2008Co-Authors: Matthew A Bertone, Gregory W Courtney, Brian M WiegmannAbstract:Relationships among families of the lower Diptera (formerly suborder 'Nematocera') have been exceptionally difficult to resolve. Multiple hypotheses based on morphology have been proposed to identify the earliest lineages of flies and place the phylogenetic origin of the higher flies (Brachycera), but convincing support is limited. Here we resolve relationships among the major groups of lower Diptera using sequence data from four nuclear markers, including both ribosomal (28S rDNA) and protein-coding (CAD, TPI and PGD) genes. Our results support both novel and traditional arrangements. Most unexpectedly, the small, highly-specialized family Deuterophlebiidae appears to be sister to all remaining Diptera. Other results include the resolution of the traditional infra-orders Culicomorpha (including a novel superfamily Simulioidea ¼ Thaumaleidae þ Simuliidae), Tipulomorpha (Tipulidae sensu lato þ Trichoceridae) and Bibionomorpha sensu lato. We find support for a limited Psychodomorpha (Blephariceridae, Tanyderidae and Psycho- didae) and Ptychopteromorpha (Ptychopteridae), whereas the placement of several enigmatic families (Nymphomyiidae, Axymyiidae and Perissommatidae) remains ambiguous. According to genetic data, the infra-order Bibionomorpha is sister to the Brachycera. Much of the phylogenetic signal for major lineages was found in the 28S rDNA gene, whereas protein-coding genes performed variably at different levels. In addition to elucidating relationships, we also estimate the age of major lower Dipteran clades, based on molecular divergence time estimates using relaxed-clock Bayesian methods and fossil calibration points.
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congruence and controversy toward a higher level phylogeny of Diptera
Annual Review of Entomology, 1999Co-Authors: David K Yeates, Brian M WiegmannAbstract:The order Diptera (true flies) is one of the most species-rich and ecologically diverse clades of insects. The order probably arose in the Permian, and the main lineages of flies were present in the Triassic. A novel recent proposal suggests that Strepsiptera are the sister-order to Diptera. Within Diptera, evidence is convincing for the monophyly of Culicomorpha, Blephariceromorpha, and Tipulomorpha but weak for the monophyly of the other basal infraorders and for the relationships among them. The lower Diptera (Nematocera) is paraphyletic with respect to Brachycera, and morphological evidence suggests the sister-group of Brachycera lies in the Psychodomorpha. Recent analyses suggest Tipulomorpha are closer to the base of Brachycera than to the base of Diptera. Brachycera are undoubtedly monophyletic, but relationships between the basal lineages of this group are poorly understood. The monophyly of Stratiomyomorpha, Xylophagomorpha, Tabanomorpha, and Muscomorpha is well supported. Eremoneura, and its constituent clades Empidoidea and Cyclorrhapha, are monophyletic. The sister-group of Eremoneura is likely to be part or all of Asiloidea. Several viewpoints on the homology of the male genitalia of eremoneuran flies are discussed. Phylogenetic analyses suggest that lower Cyclorrhapha (Aschiza) are paraphyletic; however, schizophoran monophyly is well supported. The monophyly of Acalyptratae is not well-founded and the relationships between acalyptrate superfamilies remain obscure. Recent advances document the monophyly of the families of Calyptratae and the relationships among them. Areas critical to future advances in understanding Dipteran phylogeny include the relationships among the basal infraorders of Diptera and Brachycera and the relationships between the superfamilies of acalyptrates. Progress in Dipteran phylogenetics will accelerate with the exploration of novel data sources and the formulation of hypotheses in an explicitly quantitative framework.
Markus Friedrich - One of the best experts on this subject based on the ideXlab platform.
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molecular phylogenetics at the felsenstein zone approaching the strepsiptera problem using 5 8s and 28s rdna sequences
Molecular Phylogenetics and Evolution, 1998Co-Authors: Ui W Hwang, Diethard Tautz, Markus FriedrichAbstract:Abstract Recent efforts to reconstruct the phylogenetic position of the insect order Strepsiptera have elicited a major controversy in molecular phylogenetics. We sequenced the 5.8S rDNA and major parts of the 28S rDNA 5′ region of the strepsipteran speciesStylops melittae.Their evolutionary dynamics were analyzed together with previously published insect rDNA sequences to identify tree estimation bias risks and to explore additional sources of phylogenetic information. Several major secondary structure changes were found as being autapomorphic for the Diptera, the Strepsiptera, or the Archaeognatha. Besides elevated substitution rates a significant AT bias was present in Dipteran and strepsipteran 28S rDNA which, however, was restricted to stem sites in the Diptera while also affecting single-stranded sites in the Strepsiptera. When Dipteran taxa were excluded from tree estimation all methods consistently supported the placement of Strepsiptera to within the Holometabola. When Dipteran taxa were included maximum likelihood continued to favor a sister-group relationship of Strepsiptera with Mecoptera while remaining methods strongly supported a sister-group relationship with Diptera. Parametric bootstrap analysis revealed maximum likelihood as a consistent estimator if rate heterogeneity across sites was taken into account. Though the position of Strepsiptera within Holometabola remains elusive, we conclude that the evolution of Dipteran and strepsipteran rDNA involved similar yet independent changes of substitution parameters.
James F. Wallman - One of the best experts on this subject based on the ideXlab platform.
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The Blow Fly Waltz: Field and Laboratory Observations of Novel and Complex Dipteran Courtship Behavior
Journal of Insect Behavior, 2019Co-Authors: Nathan J. Butterworth, Phillip G. Byrne, James F. WallmanAbstract:Complex courtship has been well documented in the Diptera. However, studies have focused on a limited number of taxa and mostly using lab populations, where behavior can differ substantially compared to nature. To broaden our understanding of Dipteran courtship, studies are required in a wider range of species, across both wild and captive populations. The blow flies (Diptera: Calliphoridae) include some of the most commonly encountered flies, yet courtship has been documented in less than 1% of species and is reported to be brief and simple throughout the family. To further investigate blow fly courtship, and to assess the effect of captivity on behavior, this study aimed to document the courtship of a habitat specialist that is endemic to Australasia, Chrysomya flavifrons . Video footage of wild and captive groups was recorded and analyzed using behavioral analysis software. The specific aims were 1) to quantify the behavioral sequences that constitute courtship and 2) to compare courtship between wild and captive flies. We found that the courtship behavior of Ch. flavifrons was complex and stereotyped, consisting of five discrete behaviors, which starkly contrasts with the simple courtship observed in most calliphorids. All of these stereotyped behaviors were observed in both wild and captive groups. However, the proportion of time males spent on these behaviors differed substantially. These findings highlight that blow fly courtship behavior may be more complex than currently perceived, and that careful consideration should be given to the influence of the laboratory environment in future studies of fly behavior.
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the evolution of myiasis in humans and other animals in the old and new worlds part ii biological and life history studies
Trends in Parasitology, 2006Co-Authors: Jamie R Stevens, James F. Wallman, Domenico Otranto, Richard Wall, Thomas PapeAbstract:Myiasis, which is the Dipteran parasitism of living vertebrates, occurs in several forms – ranging from benign to fatal, opportunistic to obligate – and seems to have evolved through two distinct routes: saprophagous and sanguinivorous. However, the convergent evolution of morphological and life-history traits seems to have had a major role in confusing the overall picture of how myiasis evolved and this simplistic division is further complicated by the existence of both ectoparasitic and endoparasitic species of myiasis-causing Diptera, the evolutionary affinities of which remain to be resolved. As discussed in part I of this review, if we are to elucidate how the different forms of parasitism arose, it is essential to separate the evolution of the various groups of myiasis-causing flies from the evolution of the myiasis habit per se . Accordingly, whereas we focused on recent landmark phylogenetics studies in part I, we use this framework to analyse relevant biochemical, immunological, behavioural, biogeographical and fossil evidence to elucidate the evolution of myiasis in part II.
Jan Kwiatowski - One of the best experts on this subject based on the ideXlab platform.
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structure and sequence of the cu zn sod gene in the mediterranean fruit fly ceratitis capitata intron insertion deletion and evolution of the gene
Molecular Phylogenetics and Evolution, 1992Co-Authors: Jan Kwiatowski, Douglas Skarecky, Francisco J AyalaAbstract:We have cloned a 4-kb region encompassing the Cu,Zn superoxide dismutase (Sod) gene from a genomic library of the Mediterranean fruit fly, Ceratitis capitata, using a cDNA probe from Drosophila melanogaster. The coding sequence of 462 bases is equally as long as that in Drosophila species. The rate of amino acid replacement over the past 100 million years is approximately the same in the Diptera and in mammals, thus excluding the hypothesis (proposed to account for an apparent acceleration in rate of evolution of Sod over geological time) that the evolution of the SOD protein is much higher in the mammals than in other organisms. The coding region is interrupted by two introns in Ceratitis, whereas only one occurs in Drosophila. Phylogenetic comparisons indicate that the second intron was present in the common Dipteran ancestor, but was lost shortly after the divergence of the Drosophila lineage from other Diptera. Analysis of the exon/intron structure of Sod in various animal phyla, plants, and fungi indicates that intron insertions as well as deletions have occurred in the evolution of the Sod gene.
Gregory W Courtney - One of the best experts on this subject based on the ideXlab platform.
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Ecological and Societal Services of Aquatic Diptera
MDPI AG, 2019Co-Authors: Peter H Adler, Gregory W CourtneyAbstract:More than any other group of macro-organisms, true flies (Diptera) dominate the freshwater environment. Nearly one-third of all flies—roughly 46,000 species—have some developmental connection with an aquatic environment. Their abundance, ubiquity, and diversity of adaptations to the aquatic environment position them as major drivers of ecosystem processes and as sources of products and bioinspiration for the benefit of human society. Larval flies are well represented as ecosystem engineers and keystone species that alter the abiotic and biotic environments through activities such as burrowing, grazing, suspension feeding, and predation. The enormous populations sometimes achieved by aquatic flies can provide the sole or major dietary component for other organisms. Harnessing the services of aquatic Diptera for human benefit depends on the ingenuity of the scientific community. Aquatic flies have played a role as indicators of water quality from the earliest years of bioassessment. They serve as indicators of historical and future ecological and climate change. As predators and herbivores, they can serve as biological control agents. The association of flies with animal carcasses in aquatic environments provides an additional set of tools for forensic science. The extremophilic attributes of numerous species of Diptera offer solutions for human adaptation to harsh terrestrial and extraterrestrial environments. The potential pharmaceutical and industrial applications of the symbiotic microbial community in extremophilic Diptera are better explored than are those of Dipteran chemistry. Many flies provide valuable ecological and human services as aquatic immatures, but are also pests and vectors of disease agents as terrestrial adults. The scientific community, thus, is challenged with balancing the benefits and costs of aquatic Diptera, while maintaining sustainable populations as more species face extinction
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first μ ct based 3d reconstruction of a Dipteran larva the head morphology of protanyderus tanyderidae and its phylogenetic implications
Journal of Morphology, 2012Co-Authors: Benjamin Wipfler, Gregory W Courtney, Douglas A Craig, Rolf G BeutelAbstract:The larval head of Protanyderus was exam- ined and documented using innovative techniques, with emphasis on internal structures. A chart listing all head muscles of Dipteran larvae and other holometabolan groups is presented in the Supporting Information. The results are compared to conditions found in other nematoceran line- ages. The larval head of Protanyderus is characterized mainly by plesiomorphic character states such as the com- plete and largely exposed head capsule, the long coronal suture, V-shaped frontal sutures, lateral antennal insertion areas, a transverse labrum, a nearly horizontal plane of mandibular movements, mandibles lacking a movable dis- tal part, a mesal hook and mesal or distal combs, separated maxillary endite lobes, a comparatively complete array of muscles, and a brain only partly located within the head capsule. An anteriorly toothed hypostomal plate and dense labral brushes of microtrichiae are also likely groundplan features of Diptera. The pharyngeal filter is a possible apo- morphy of Diptera excl. Deuterophlebiidae (or Deutero- phlebiidae 1 Nymphomyiidae). The messors have also likely evolved early in the Dipteran crown group but are absent in the groundplan. The phylogenetic interpretation of externolateral plates with growth lines is ambiguous. Autapomorphies of Tanyderidae are differences between the third and fourth instar larvae, the roof-like extension above the antennal insertion area, the dorsal endocarina, and the posterodorsal internal ridge. The phylogenetic posi- tion of Tanyderidae is controversial, but features of the larval head do not support a proposed sistergroup relation- ship between Tanyderidae and Psychodidae. Both groups differ in many features of the larval head, and we did not identify a single potential synapomorphy. Larval charac- ters alone are insufficient for a reliable phylogenetic recon- struction, though they vary greatly and apparently contain phylogenetic information. The evaluation of these features in the context of robust molecular phylogenies will be a sound basis for the reconstruction of complex evolutionary scenarios for the megadiverse Diptera. J. Morphol.
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phylogenetics and temporal diversification of the earliest true flies insecta Diptera based on multiple nuclear genes
Systematic Entomology, 2008Co-Authors: Matthew A Bertone, Gregory W Courtney, Brian M WiegmannAbstract:Relationships among families of the lower Diptera (formerly suborder 'Nematocera') have been exceptionally difficult to resolve. Multiple hypotheses based on morphology have been proposed to identify the earliest lineages of flies and place the phylogenetic origin of the higher flies (Brachycera), but convincing support is limited. Here we resolve relationships among the major groups of lower Diptera using sequence data from four nuclear markers, including both ribosomal (28S rDNA) and protein-coding (CAD, TPI and PGD) genes. Our results support both novel and traditional arrangements. Most unexpectedly, the small, highly-specialized family Deuterophlebiidae appears to be sister to all remaining Diptera. Other results include the resolution of the traditional infra-orders Culicomorpha (including a novel superfamily Simulioidea ¼ Thaumaleidae þ Simuliidae), Tipulomorpha (Tipulidae sensu lato þ Trichoceridae) and Bibionomorpha sensu lato. We find support for a limited Psychodomorpha (Blephariceridae, Tanyderidae and Psycho- didae) and Ptychopteromorpha (Ptychopteridae), whereas the placement of several enigmatic families (Nymphomyiidae, Axymyiidae and Perissommatidae) remains ambiguous. According to genetic data, the infra-order Bibionomorpha is sister to the Brachycera. Much of the phylogenetic signal for major lineages was found in the 28S rDNA gene, whereas protein-coding genes performed variably at different levels. In addition to elucidating relationships, we also estimate the age of major lower Dipteran clades, based on molecular divergence time estimates using relaxed-clock Bayesian methods and fossil calibration points.
