Do cladistic and morphometric data capture common patterns of morphological disparity?

he distinctly non-random diversity of organis-mal form manifests itself in discrete clusters of taxa thatshare a common body plan. As a result, analyses of disparityrequire a scalable comparative framework. The difficulties ofapplying geometric morphometrics to disparity analyses ofgroups with vastly divergent body plans are overcome partlyby the use of cladistic characters. Character-based disparityanalyses have become increasingly popular, but it is not clearhow they are affected by character coding strategies or revi-sions of primary homology statements. Indeed, whether cla-distic and morphometric data capture similar patterns ofmorphological variation remains a moot point. To addressthis issue, we employ both cladistic and geometric morpho-metric data in an exploratory study of disparity focussing oncaecilian amphibians. Our results show no impact on relativeintertaxon distances when different coding strategies for cla-distic characters were used or when revised concepts ofhomology were considered. In all instances, we found no sta-tistically significant difference between pairwise Euclideanand Procrustes distances, although the strength of the corre-lation among distance matrices varied. This suggests that cla-distic and geometric morphometric data appear tosummarize morphological variation in comparable ways.Our results support the use of cladistic data for characteriz-ing organismal disparity