02479nas a2200265   4500008004100000245010000041210006900141260000800210300001200218490000700230520173500237653001401972653001501986653002402001653001502025653001002040653001702050653001802067653000802085653001602093100002102109700002002130700002202150856004102172       2002                        eng d00aSimultaneous analysis of the basal lineages of Hymenoptera (Insecta) using sensitivity analysis0 aSimultaneous analysis of the basal lineages of Hymenoptera Insec  cOCT  a455-4840 v183 aThe first simultaneous analysis of molecular and morphological data of basal hymenopterans that includes exemplars from all families is presented. DNA sequences (of approximately 2000-2700 by for each taxon) from the nuclear genes 18S and 285 and the mitochondrial genes 16S and CO1 have been sequenced for 39 taxa (four outgroup taxa, 29 symphytans, and six apocritans). These DNA sequences and 236 morphological characters from Vihelmsen [Zool. J. Linnean Soc. 131 (2001) 393] were analyzed separately as well as simultaneously. All analyses were performed on unaligned sequences, using the optimization alignment (= direct optimization) method. Sensitivity analysis sensu Wheeler [Syst. Biol. 44 (1995) 321] was applied by analyzing the data under nine different combinations of analysis parameter values. The superfamily level relationships of basal hymenopterans as proposed by Vilhelmsen [Zool. J. Linnean Soc. 131 (2001) 393] and Ronquist et al. [Zool. Scr. 28 (1999) 13] are mostly confirmed, except that Pamphilioidea is the sister group to Tenthredinoidea s.l. and that Anaxyelidae (i.e., Syntexis libocedrii) and Siricidae are supported as a monophyletic group, partly reestablishing the traditional concept of Siricoidea. The resulting hypothesis that best represents the combined evidence from morphology and DNA. sequences is (Xyeloidea (Tenthredinoidea s.l. Pamphilioidea) (Cephoidea (Siricoidea (Xiphydrioidea (Orussidae Apocrita))))), with Siricoidea = Anaxyelidae + Siricidae. The phylogenetic system within Tenthredinoidea s.l., derived from the combined evidence, is (Blasticotomidae (Tenthredinidae including Diprionidae (Cimbicidae (Argidae Pergidae)))). (C) 2002 Elsevier Science (USA). All rights reserved.10aalignment10acongruence10adirect optimization10amorphology10amtDNA10aoptimization10aphylogenetics10apoy10asensitivity1 aSchulmeister, S.1 aWheeler, W., C.1 aCarpenter, J., M.  u<u><Go to ISI>://000179061500001</u>01993nas a2200241   4500008004100000245006200041210006000103260000800163300001200171490000700183520137700190653002401567653000801591653001401599653000801613653001501621653001801636653000801654653001601662653001401678100001801692856004101710       2005                        eng d00aDirect optimization, affine gap costs, and node stability0 aDirect optimization affine gap costs and node stability  cSEP  a641-6530 v363 aThe outcome of a phylogenetic analysis based on DNA sequence data is highly dependent on the homology-assignment step and may vary with alignment parameter costs. Robustness to changes in parameter costs is therefore a desired quality of a data set because the final conclusions will be less dependent on selecting a precise optimal cost set. Here, node stability is explored in relationship to separate versus combined analysis in three different data sets, all including several data partitions. Robustness to changes in cost sets is measured as number of successive changes that can be made in a given cost set before a specific clade is lost. The changes are in all cases base change cost, gap penalties, and adding/removing/changing affine gap costs. When combining data partitions, the number of clades that appear in the entire parameter space is not remarkably increased, in some cases this number even decreased. However, when combining data partitions the trees from cost sets including affine gap costs were always more similar than the trees were from cost sets without affine gap costs. This was not the case when the data partitions were analyzed independently. When data sets were combined similar to 80% of the clades found under cost sets including affine gap costs resisted at least one change to the cost set. (c) 2005 Elsevier Inc. All rights reserved.10adirect optimization10adna10aevolution10agap10amorphology10aphylogenetics10apoy10asensitivity10astability1 aAagesen, Lone  u<u><Go to ISI>://000231591500017</u>