@article {7810,
	title = {Homology and the optimization of DNA sequence data},
	journal = {Cladistics},
	volume = {17},
	year = {2001},
	note = {PDF},
	pages = {S3-S11},
	keywords = {direct optimization, dna, homology, molecules, phylogenetics, poy},
	author = {Wheeler, Ward}
}
@article {7516,
	title = {Phylogeny and biogeography of cichlid fishes (Teleostei : Perciformes : Cichlidae)},
	journal = {Cladistics},
	volume = {20},
	number = {6},
	year = {2004},
	note = {PDFTimes Cited: 3ArticleEnglishCited References Count: 89896wq},
	month = {DEC},
	pages = {501-517},
	abstract = {Family level molecular phylogenetic analyses of cichlid fishes have generally suffered from a limited number of characters and/or poor taxonomic sampling across one or more major geographic assemblage, and therefore have not provided a robust test of early intrafamilial diversification. Herein we use both nuclear and mitochondrial nucleotide characters and direct optimization to reconstruct a phylogeny for cichlid fishes. Representatives of major cichlid lineages across all geographic assemblages are included, as well as nearly twice the number of characters as any prior family-level study. In a strict consensus of 81 equally most-parsimonious hypotheses, based on the simultaneous analysis of 2222 aligned nucleotide characters from two mitochondrial and two nuclear genes, four major subfamilial lineages are recovered with strong support. Etroplinae, endemic to Madagascar (Paretroplus) and southern Asia (Etroplus), is recovered as the sister taxon to the remainder of Cichlidae. Although the South Asian cichlids are monophyletic, the Malagasy plus South Asian lineages are not. The remaining Malagasy lineage, Ptychochrominae, is monophyletic and is recovered as the sister group to a clade comprising the African and Neotropical cichlids. The African (Pseudocrenilabrinae) and Neotropical (Cichlinae) lineages are each monophyletic in this reconstruction. The use of multiple molecular markers, from both mitochondrial and nuclear genes, results in a phylogeny that in general exhibits strong support, notably for early diversification events within Cichlidae. Results further indicate that Labroidei is not monophyletic, and that the sister group to Cichlidae may comprise a large and diverse assemblage of percomorph lineages. This hypothesis may at least partly explain why morphological studies that have attempted to place Cichlidae within Percomorpha, or that have tested cichlid monophyly using only "labroid" lineages, have met with only limited success. (c) The Willi Hennig Society 2004.},
	keywords = {biogeography, direct optimization, dna, evolution, fishes, phylogeny, poy},
	url = {<u><Go to ISI>://000226965400001</u>},
	author = {Sparks, J. S. and Smith, W. L.}
}
@article {5697,
	title = {Direct optimization, affine gap costs, and node stability},
	journal = {Molecular Phylogenetics and Evolution},
	volume = {36},
	number = {3},
	year = {2005},
	note = {PDFTimes Cited: 0ArticleEnglishCited References Count: 57960lh},
	month = {SEP},
	pages = {641-653},
	abstract = {The 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.},
	keywords = {direct optimization, dna, evolution, gap, morphology, phylogenetics, poy, sensitivity, stability},
	url = {<u><Go to ISI>://000231591500017</u>},
	author = {Aagesen, Lone}
}
