INVESTIGADORES
EZCURRA Martin Daniel
congresos y reuniones científicas
Título:
Testing the effect of different sampling strategies in palaeontological data matrixes analysed using maximum parsimony: preliminary results
Autor/es:
RONAYNE, E. E.; EZCURRA, M. D.
Reunión:
Congreso; 30 Jornadas Argentinas de Paleontologia de Vertebrados; 2016
Resumen:
Nowadays phylogenetic analyses focused on the higher-level interrelationships of taxonomically diverse clades have become common. However, the logical basis of the sampling strategies of such diverse clades is frequently poorly explored. To test the effect of sampling strategies in phylogenetic analyses we reanalysed using maximum parsimony 15 large palaeontological matrixes (>70 terminals) applying eight different subsamplings. The strategies were conducted combining the subsampling of two or three of the most basal and/or most informative (lowest number of missing data and polymorphisms) taxa of each clade of the original topology. The subsampling results were measured as the ratio of clades and synapomorphies also present in the original analysis, and with a modified Robinson?Foulds distance (proportion of bipartitions that differ between both trees). The reanalysed matrixes show that the ratio of recovered original clades and synapomorphies ranged 52−85% and 34−50%, respectively, highlighting the impact that sampling strategies may have in phylogenetic results. The sampling of the two or three most informative terminals recovers higher clade ratios than using the most basal terminals, and the usage of the most informative terminals founds significantly higher clade ratios than their combination with the most basal taxa. The sampling of the most basal terminals plus that with the highest number of accumulated steps (e.g. extant taxa within a Mesozoic sample) significantly outperforms in topology and ratio of original synapomorphies most of the other strategies. Therefore, our results suggest the sampling of at least three of the most informative taxa, excluding extant or highly derived terminals.