03969nas a2200217   4500008004100000245007600041210006900117260010400186300001200290490000700302520319100309653001703500653001403517653001403531653002103545653002003566653002003586653002103606100001503627856010903642       2006                        eng d00aPhylogeny of Taenia: Species definitions and origins of human parasites0 aPhylogeny of Taenia Species definitions and origins of human par  aELSEVIER HOUSE, BROOKVALE PLAZA, EAST PARK SHANNON, CO, CLARE, 00000, IRELANDbELSEVIER IRELAND LTD  aS23-S300 v553 aPhylogeny is fundamental as it constrains explanations about history and forms our foundation for recognizing and diagnosing species. In the absence of such a framework taxonomists historically relied on intuitive processes, personal judgment and authority, often embracing a typological view of species that disregarded otherwise unequivocal historical and biological criteria. Species of Taenia are among the most characteristic tapeworms infecting carnivores and humans as definitive hosts and indeed Taemidae is unique among the Eucestoda in requiring 2 obligate mammalian hosts for transmission; a high percentage (>80%) of life cycles have been completely elucidated among the approximately 45 species and nominal subspecies of Taenia. Until recently there had been no comprehensive attempts at reconstruction of a phylogeny among these important parasites. Such analyses have allowed us to explore the origins and evolution of those independent species of Taenia that occur in humans (T saginata, T asiatica, and T solium) and to understand the ecological and historical processes serving as determinants of biogeography and host-association. These studies supported the status of T asiatica as a valid species and diagnosed a relationship as the sister-species of T saginata. These conclusions contrasted with a diversity of opinions that would subsume T asiatica as a subspecies. Recognition of a species constitutes a specific and testable hypothesis, is not an arbitrary decision and is most appropriately assessed in the context of phylogenetic or historical data. Considering macrospecies, a process has been outlined by Brooks and McLennan [Brooks DR, McLennan DA. The nature of diversity: an evolutionary voyage of discovery. University of Chicago Press: Chicago; 2002] as follows: (1) Discovery: a systematist describes the species; (2) Phylogenetic reconstruction; (3) Evaluation I: do sister-species show geographical overlap-are they sympatric or allopatric (use phylogeny+geographical distributions)? (4) Evaluation II: are sister-species reproductively isolated based on information from natural history, ecology and reproductive biology? Species may be viewed in the context of microevolutionary and macroevolutionary processes. For instance, microspecies are defined in ecological time and involve populations and contemporary process that are potentially reversible (reticulate). In contrast, macrospecies as exemplified by T saginata and T asiatica are divergent lineages resulting from processes in evolutionary time where an ancestor has undergone a permanent split that is non-reversible (non-reticulate). Applying these criteria in evaluation of T saginata and T asiatica, it becomes clear that in evolutionary time these represent historical lineages with independent spatial and temporal trajectories, having separated from a common ancestor near 0.78 to 1.71 MYBP in Africa, or Eurasia. In ecological time, sympatry, reproductive isolation, and differences in life history evident for T saginata and T asiatica as observed in China, and perhaps other regions of Southeast Asia, further serve to validate these taeniids. Published by Elsevier Ireland Ltd.10abiogeography10aevolution10aphylogeny10aspecies concepts10aTaenia asiatica10aTaenia saginata10aTaenia tapeworms1 aHoberg, EP  uhttps://nematoda.myspecies.info/content/phylogeny-taenia-species-definitions-and-origins-human-parasites02370nas a2200193   4500008004100000245008600041210006900127260008500196300001200281490000700293520163900300653001301939653002101952653001401973653002101987653002002008100002502028856012302053       2006                        eng d00aGenetic variability and adaptive evolution in parthenogenetic root-knot nematodes0 aGenetic variability and adaptive evolution in parthenogenetic ro  aMACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLANDbNATURE PUBLISHING GROUP  a282-2890 v963 aRoot-knot nematodes (RKN) of the genus Meloidogyne are biotrophic plant parasites of major agricultural importance, which exhibit very variable modes of reproduction, from classical amphimixis to mitotic parthenogenesis. This review focuses on those RKN species that reproduce exclusively by mitotic parthenogenesis ( apomixis), in contrast to those that have meiotic/ amphimitic events in their life cycle. Although populations of clonal organisms are often represented as being ecologically isolated and evolutionary inert, a considerable volume of literature provides evidence that asexual RKN are neither: they are widely distributed, extremely polyphagous, and amenable to selection and adaptive variation. The ancestors of the genus are unknown, but it is assumed that the parthenogenetic RKN have evolved from amphimictic species through hybridization and subsequent aneuploidization and polyploidization events. Molecular studies have indeed confirmed that the phylogenetic divergence between meiotic and mitotic RKN lineages occurred early, and have revealed an unexpected level of clonal diversity among populations within apomictic species. Laboratory experiments have shown that asexual RKN can rapidly adapt to new environmental constraints (eg host resistance), although with some fitness costs. Lastly, the molecular and chromosomal mechanisms that could contribute to genome plasticity leading to persistent genetic variation and adaptive evolution in apomictic RKN are discussed. It is concluded that RKN provide an excellent model system in which to study the dynamic nature and adaptive potential of clonal genomes.10aapomixis10aclonal diversity10aevolution10aMeloidogyne spp.10aparthenogenesis1 aCastagnone-Sereno, P  uhttps://nematoda.myspecies.info/content/genetic-variability-and-adaptive-evolution-parthenogenetic-root-knot-nematodes01897nas a2200205   4500008004100000245005900041210005900100260006700159300001200226490000700238520124600245653001201491653001401503653001801517653001201535653002001547100001401567700001501581856009501596       2004                        eng d00aMolecular clocks do not support the Cambrian explosion0 aMolecular clocks do not support the Cambrian explosion  aGREAT CLARENDON ST, OXFORD OX2 6DP, ENGLANDbOXFORD UNIV PRESS  a387-3900 v223 aThe fossil record has long supported the view that most animal phyla originated during a brief period approximately 520 MYA known as the Cambrian explosion. However, molecular data analyses over the past 3 decades have found deeper divergences among animals (similar to800 to 1,200 MYA), with and without the assumption of a global molecular clock. Recently, two studies have instead reported time estimates apparently consistent with the fossil record. Here, we demonstrate that methodological problems in these studies cast doubt on the accuracy and interpretations of the results obtained. In the study by Peterson et al., young time estimates were obtained because fossil calibrations were used as maximum limits rather than as minimum limits, and not because invertebrate calibrations were used. In the study by Aris-Brosou and Yang, young time estimates were obtained because of problems with rate models and other methods specific to the study, and not because Bayesian methods were used. This also led to many anomalous findings in their study, including a primate-rodent divergence at 320 MYA. With these results aside, molecular clocks continue to support a long period of animal evolution before the Cambrian explosion of fossils.10aanimals10aevolution10afossil record10aMetazoa10atime estimation1 aBlair, JE1 aHedges, SB  uhttps://nematoda.myspecies.info/content/molecular-clocks-do-not-support-cambrian-explosion03474nas a2200469   4500008004100000245008900041210006900130260009000199300001200289490000700301520201200308653001602320653002302336653001602359653001202375653001402387653002602401653002102427653001302448653001402461653003202475653001502507653001602522653001302538653001602551653001302567100002602580700002502606700001702631700002802648700002902676700002602705700001402731700002102745700001502766700002002781700002402801700002202825700002102847700002502868856011102893       2007                        eng d00aAn improved molecular phylogeny of the Nematoda with special emphasis on marine taxa0 aimproved molecular phylogeny of the Nematoda with special emphas  a525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USAbACADEMIC PRESS INC ELSEVIER SCIENCE  a622-6360 v423 aPhylogenetic reconstructions of relations within the phylum Nematoda are inherently difficult but have been advanced with the introduction of large-scale molecular-based techniques. However, the most recent revisions were heavily biased towards terrestrial and parasitic species and greater representation of clades containing marine species (e.g. Araeolaimida, Chromadorida, Desmodorida, Desmoscolecida, Enoplida, and Monhysterida) is needed for accurate coverage of known taxonomic diversity. We now add small subunit ribosomal DNA (SSU rDNA) sequences for 100 previously un-sequenced species of nematodes, including 46 marine taxa. SSU rDNA sequences for > 200 taxa have been analysed based on Bayesian inference and LogDet-transformed distances. The resulting phylogenies provide support for (i) the re-classification of the Secernentea as the order Rhabditida that derived from a common ancestor of chromadorean orders Araeolaimida, Chromadorida, Desmodorida, Desmoscolecida, and Monhysterida and (ii) the position of Bunonema close to the Diplogasteroidea in the Rhabditina. Other, previously controversial relationships can now be resolved more clearly: (a) Alaimus, Campydora, and Trischistoma belong in the Enoplida, (b) Isolaimium is placed basally to a big clade containing the Axonolaimidae, Plectidae, and Rhabditida, (c) Xyzzors belongs in the Desmodoridae, (d) Comesomatidae and Cyartonema belongs in the Monhysterida, (e) Globodera belongs in the Hoplolaimidae and (0 Paratylenchus dianeae belongs in the Criconematoidea. However, the SSU gene did not provide significant support for the class Chromadoria or clear evidence for the relationship between the three classes, Enoplia, Dorylaimia, and Chromadoria. Furthermore, across the whole phylum, the phylogenetically informative characters of the SSU gene are not informative in a parsimony analysis, highlighting the short-comings of the parsimony method for large-scale phylogenetic modelling. (c) 2006 Elsevier Inc. All rights reserved.10aAdenophorea10aBayesian inference10aChromadorea10aEnoplea10aevolution10aLogDet transformation10aMarine nematodes10aNematoda10aparsimony10aphylogenetic reconstruction10aRhabditida10aSecernentea10aSSU rDNA10asystematics10ataxonomy1 aMeldal, Birgit, H. M.1 aDebenham, Nicola, J.1 aDe Ley, Paul1 aDe Ley, Irma, Tandingan1 aVanfleteren, Jacques, R.1 aVierstraete, Andy, R.1 aBert, Wim1 aBorgonie, Gaetan1 aMoens, Tom1 aTyler, Paul, A.1 aAusten, Melanie, C.1 aBlaxter, Mark, L.1 aRogers, Alex, D.1 aLambshead, P., J. D.  uhttps://nematoda.myspecies.info/content/improved-molecular-phylogeny-nematoda-special-emphasis-marine-taxa01723nas a2200265   4500008004100000245015000041210006900191260007600260300001200336490000700348520075700355653001801112653001401130653001401144653001401158653001501172653001701187100002101204700002201225700001501247700001601262700001901278700002301297856013701320       2008                        eng d00aNew data from an enigmatic phylum: evidence from molecular sequence data supports a sister-group relationship between Loricifera and Nematomorpha0 aNew data from an enigmatic phylum evidence from molecular sequen  a9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLANDbBLACKWELL PUBLISHING  a231-2390 v463 aLoricifera is one of the most recently discovered animal phyla. So far, the group has been considered closely related to Kinorhyncha and Priapulida, and assigned to the ecdysozoan clade Cycloneuralia. Using Bayesian inference, we present the first phylogeny that includes 18S rRNA and Histone 3 sequences from two species of Loricifera. Intriguingly, we find support for a sister-group relationship between Loricifera and Nematomorpha. Such relationship has not been suggested previously and the results imply that a revision of our conception of early ecdysozoan evolution is required. Additionally, the data suggest that evolution through progenesis (sexual maturation of larvae) may have played an important role among the ancestral cycloneuralians.10aCycloneuralia10aEcdysozoa10aevolution10aphylogeny10aprogenesis10aScalidophora1 aSorensen, M., V.1 aHebsgaard, M., B.1 aHeiner, I.1 aGlenner, H.1 aWillerslev, E.1 aKristensen, R., M.  uhttps://nematoda.myspecies.info/content/new-data-enigmatic-phylum-evidence-molecular-sequence-data-supports-sister-group-relationshi