02701nas a2200421   4500008004100000245009300041210006900134300001400203490000700217520142500224653000801649653001801657653001201675653001801687653000801705653001401713653002201727653001601749653003201765653002601797653001801823653002901841653002801870653001401898653002801912653003001940653001401970653001401984653002501998653002402023653000802047653001002055653002602065653002002091100002002111700001802131856013002149       1998                        eng d00aHierarchical analysis of variation in the mitochondrial 16S rRNA gene among Hymenoptera.0 aHierarchical analysis of variation in the mitochondrial 16S rRNA  a1728-17430 v153 aNucleotide sequences from a 434-bp region of the 16S rRNA gene were analyzed for 65 taxa of Hymenoptera (ants, bees, wasps, parasitoid wasps, sawflies) to examine the patterns of variation within the gene fragment and the taxonomic levels for which it shows maximum utility in phylogeny estimation. A hierarchical approach was adopted in the study through comparison of levels of sequence variation among taxa at different taxonomic levels. As previously reported for many holometabolous insects, the 16S data reported here for Hymenoptera are highly AT-rich and exhibit strong site-to-site variation in substitution rate. More precise estimates of the shape parameter (alpha) of the gamma distribution and the proportion of invariant sites were obtained in this study by employing a reference phylogeny and utilizing maximum-likelihood estimation. The effectiveness of this approach to recovering expected phylogenies of selected hymenopteran taxa has been tested against the use of maximum parsimony. This study finds that the 16S gene is most informative for phylogenetic analysis at two different levels: among closely related species or populations, and among tribes, subfamilies, and families. Maximization of the phylogenetic signal extracted from the 16S gene at higher taxonomic levels may require consideration of the base composition bias and the site-to-site rate variation in a maximum-likelihood framework.10a16S10a16S: genetics10aAnimals10aBase Sequence10aDNA10aevolution10aGenetic Variation10aHymenoptera10aHymenoptera: classification10aHymenoptera: genetics10aMitochondrial10aMitochondrial: chemistry10aMitochondrial: genetics10aMolecular10aMolecular Sequence Data10aNucleic Acid Conformation10aphylogeny10aRibosomal10aRibosomal: chemistry10aRibosomal: genetics10aRNA10aWasps10aWasps: classification10aWasps: genetics1 aWhitfield, J.B.1 aCameron, S.A.  uhttps://insectafgseag.myspecies.info/en/content/hierarchical-analysis-variation-mitochondrial-16s-rrna-gene-among-hymenoptera02079nas a2200133   4500008004100000245009000041210006900131300001200200490000700212520157100219100001501790700001701805856012301822       1999                        eng d00aEvolutionary dynamics of a mitochondrial rearrangement "hot spot" in the Hymenoptera.0 aEvolutionary dynamics of a mitochondrial rearrangement hot spot   a298-3090 v163 aThe arrangement of tRNA genes at the junction of the cytochrome oxidase II and ATPase 8 genes was examined across a broad range of Hymenoptera. Seven distinct arrangements of tRNA genes were identified among a group of wasps that have diverged over the last 180 Myr (suborder Apocrita); many of the rearrangements represent evolutionarily independent events. Approximately equal proportions of local rearrangements, inversions, and translocations were observed, in contrast to vertebrate mitochondria, in which local rearrangements predominate. Surprisingly, homoplasy was evident among certain types of rearrangement; a reversal of the plesiomorphic gene order has arisen on three separate occasions in the Insecta, while the tRNA(H) gene has been translocated to this locus on two separate occasions. Phylogenetic analysis indicates that this gene translocation is real and is not an artifactual translocation resulting from the duplication of a resident tRNA gene followed by mutation of the anticodon. The nature of the intergenic sequences surrounding this region does not indicate that it should be especially prone to rearrangement; it does not generally have the tandem or inverted repeats that might facilitate this plasticity. Intriguingly, these findings are consistent with the view that during the evolution of the Hymenoptera, rearrangements increased at the same time that the rate of point mutations and compositional bias also increased. This association may direct investigations into mitochondrial genome plasticity in other invertebrate lineages.1 aDowton, M.1 aAustin, A.D.  uhttps://insectafgseag.myspecies.info/en/content/evolutionary-dynamics-mitochondrial-rearrangement-hot-spot-hymenoptera