A-PRIORI ESTIMATION OF PHYLOGENETIC INFORMATION CONSERVED IN ALIGNED SEQUENCES

A new phenomenological approach to explorative data analysis, the esti mation of spectra of supporting positions, allows the search for conse rved tracks left by phylogeny in DNA sequences. Spectra of supporting positions can be generated without reference to a tree topology or a m odel of sequence evolution and are therefore an ideal tool for a prior i estimation of information content of data sets. Analysis of publishe d 18S rDNA alignments shows that signal to noise relationship varies g reatly in a way not detected by conventional tree-construction methods . (C) 1998 Academic Press.