title: Correcting parsimonious trees for unseen nucleotide substitutions: the effect of dense branching as exemplified by ribonuclease.
abstract: In a study of mammalian ribonuclease evolutionary rates, we applied the Fitch-Bruschi correction to reduce the bias caused by an unequal sampling of taxa in different lineages. The correction was clearly appropriate but only up to a point. The analysis showed that the sampling of taxa within the pecora was sufficiently intense that no correction for unseen, amino acid-changing, nucleotide substitutions was required. It was also found that the ribonuclease gene was duplicated at least twice at the origin of the pecoran branch of the artiodactyls.
authors: Department of Ecology and Evolutionary Biology, University of California, Irvine 92717.
authors: W M
authors: WM
authors: Fitch
authors: J J
authors: JJ
authors: Beintema
mesh_terms: D000818:Animals; D005075:Biological Evolution; D001921:Brain / Q000201:enzymology*; D006801:Humans; D010802:Phylogeny; D012259:Ribonuclease, Pancreatic / Q000235:genetics; D012260:Ribonucleases / Q000235:genetics*; D012661:Semen / Q000201:enzymology*
chemical_list: D012260:Ribonucleases; D012259:Ribonuclease, Pancreatic