approximately doubled and the amplitude of lateral bending increased approximately threefold. Lag... more approximately doubled and the amplitude of lateral bending increased approximately threefold. Lag times (in seconds) indicating the propagation of kinematic and EMG events along the length of the centipede decreased significantly with speed. Phase lags among longitudinal sites decreased significantly with increased speed, indicating that the kinematic and EMG wavelengths increased with increased speed. EMG duration approximated 50 % of
Robust resolution of controversial higher-level groupings within Arthropoda requires additional s... more Robust resolution of controversial higher-level groupings within Arthropoda requires additional sources of characters. Toward this end, elongation factor-2 sequences (1899 nucleotides) were generated from 17 arthropod taxa (5 chelicerates, 6 crustaceans, 3 hexapods, 3 myriapods) plus an onychophoran and a tardigrade as outgroups. Likelihood and parsimony analyses of nucleotide and amino acid data sets consistently recovered Myriapoda and major chelicerate groups with high bootstrap support. Crustacea + Hexapoda (= Pancrustacea) was recovered with moderate support, whereas the conflicting group Myriapoda + Hexapoda (= Atelocerata) was never recovered and bootstrap values were always <5%. With additional nonarthropod sequences included, one indel supports monophyly of Tardigrada, Onychophora, and Arthropoda relative to molluscan, annelidan, and mammalian outgroups. New and previously published sequences from RNA polymerase II (1038 nucleotides) and elongation factor-1alpha (1092 nu...
We assessed the ability of three nuclear protein-encoding genes-elongation factor-1alpha (EF-1alp... more We assessed the ability of three nuclear protein-encoding genes-elongation factor-1alpha (EF-1alpha), RNA polymerase II (Pol II), and elongation factor-2 (EF-2)-from 59 myriapod and 12 non-myriapod species to resolve phylogenetic relationships among myriapod classes and orders. In a previous study using EF-1alpha and Pol II (2134 nt combined) from 34 myriapod taxa, Regier and Shultz recovered widely accepted classes, orders, and families but failed to resolve interclass and interordinal relationships. The result was attributed to heterogenous rates of cladogenesis (specifically, the inability of the slowly evolving sequences to capture phylogenetic signal during rapid phylogenetic diversification) but the possibility of inadequate taxon sampling or limited sequence information could not be excluded. In the present study, the myriapod taxon sample was increased by 25 taxa (73%) and sequence length per taxon was effectively doubled through addition of EF-2 (4318 nt combined). Parsimon...
... JEFFREY W. SHULTZ ... The results of this analysis reaffirmed the utility of EF-la and Pol I1... more ... JEFFREY W. SHULTZ ... The results of this analysis reaffirmed the utility of EF-la and Pol I1 for resolving higher-level arthropod relationships but also revealed limitations in the abil-ity of these genes to resolve important questions in myriapod phylogeny. ...
... Proceedings of the Royal Society of London B 267:10111019. CrossRef, PubMed, CSA. ilhavý, V... more ... Proceedings of the Royal Society of London B 267:10111019. CrossRef, PubMed, CSA. ilhavý, V. 1961. ... Cladistics Online publication date: 1-Nov-2009. Victor R. Townsend, Nouman J. Rana,Daniel N. Proud, Michael K. Moore, Philip Rock, Bruce E. Felgenhauer. ...
... Ballard et al. ... the construction of fossil-based pairwise difference curves, which estimat... more ... Ballard et al. ... the construction of fossil-based pairwise difference curves, which estimate the rate of potentially informative character change during the geological interval when a clade underwent phylogenetic diversification (eg, Mindell and Honeycutt, 1990; Gray-beal, 1994). ...
approximately doubled and the amplitude of lateral bending increased approximately threefold. Lag... more approximately doubled and the amplitude of lateral bending increased approximately threefold. Lag times (in seconds) indicating the propagation of kinematic and EMG events along the length of the centipede decreased significantly with speed. Phase lags among longitudinal sites decreased significantly with increased speed, indicating that the kinematic and EMG wavelengths increased with increased speed. EMG duration approximated 50 % of
Robust resolution of controversial higher-level groupings within Arthropoda requires additional s... more Robust resolution of controversial higher-level groupings within Arthropoda requires additional sources of characters. Toward this end, elongation factor-2 sequences (1899 nucleotides) were generated from 17 arthropod taxa (5 chelicerates, 6 crustaceans, 3 hexapods, 3 myriapods) plus an onychophoran and a tardigrade as outgroups. Likelihood and parsimony analyses of nucleotide and amino acid data sets consistently recovered Myriapoda and major chelicerate groups with high bootstrap support. Crustacea + Hexapoda (= Pancrustacea) was recovered with moderate support, whereas the conflicting group Myriapoda + Hexapoda (= Atelocerata) was never recovered and bootstrap values were always <5%. With additional nonarthropod sequences included, one indel supports monophyly of Tardigrada, Onychophora, and Arthropoda relative to molluscan, annelidan, and mammalian outgroups. New and previously published sequences from RNA polymerase II (1038 nucleotides) and elongation factor-1alpha (1092 nu...
We assessed the ability of three nuclear protein-encoding genes-elongation factor-1alpha (EF-1alp... more We assessed the ability of three nuclear protein-encoding genes-elongation factor-1alpha (EF-1alpha), RNA polymerase II (Pol II), and elongation factor-2 (EF-2)-from 59 myriapod and 12 non-myriapod species to resolve phylogenetic relationships among myriapod classes and orders. In a previous study using EF-1alpha and Pol II (2134 nt combined) from 34 myriapod taxa, Regier and Shultz recovered widely accepted classes, orders, and families but failed to resolve interclass and interordinal relationships. The result was attributed to heterogenous rates of cladogenesis (specifically, the inability of the slowly evolving sequences to capture phylogenetic signal during rapid phylogenetic diversification) but the possibility of inadequate taxon sampling or limited sequence information could not be excluded. In the present study, the myriapod taxon sample was increased by 25 taxa (73%) and sequence length per taxon was effectively doubled through addition of EF-2 (4318 nt combined). Parsimon...
... JEFFREY W. SHULTZ ... The results of this analysis reaffirmed the utility of EF-la and Pol I1... more ... JEFFREY W. SHULTZ ... The results of this analysis reaffirmed the utility of EF-la and Pol I1 for resolving higher-level arthropod relationships but also revealed limitations in the abil-ity of these genes to resolve important questions in myriapod phylogeny. ...
... Proceedings of the Royal Society of London B 267:10111019. CrossRef, PubMed, CSA. ilhavý, V... more ... Proceedings of the Royal Society of London B 267:10111019. CrossRef, PubMed, CSA. ilhavý, V. 1961. ... Cladistics Online publication date: 1-Nov-2009. Victor R. Townsend, Nouman J. Rana,Daniel N. Proud, Michael K. Moore, Philip Rock, Bruce E. Felgenhauer. ...
... Ballard et al. ... the construction of fossil-based pairwise difference curves, which estimat... more ... Ballard et al. ... the construction of fossil-based pairwise difference curves, which estimate the rate of potentially informative character change during the geological interval when a clade underwent phylogenetic diversification (eg, Mindell and Honeycutt, 1990; Gray-beal, 1994). ...
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