ACCURACY OF PARSIMONY ANALYSIS USING MORPHOLOGICAL DATA - A REAPPRAISAL

In a recent paper, W. F. Lamboy used computer simulations to evaluate the accuracy of parsimony analysis using morphological characters. Bas ed on his simulations, Lamboy concluded that parsimony analysis of mor phological data is generally highly inaccurate, that many published tr ees are likely incorrect, and that current emphasis on phylogeny recon struction using parsimony Is misplaced. In this paper we argue that th ese conclusions are the result of: 1) using an unusually small number of characters relative to the number of taxa; 2) generating true trees that contain polytomies; 3) using misleading measures of accuracy; 4) summing across a biased set of simulation results to make general con clusions; and 5) using an inappropriate index to compare simulated dat a to results in the real world. We provide recommendations for designi ng more rigorous simulations of phylogenetic questions, and summarize current knowledge of the performance of parsimony analysis based on ot her simulation studies. In contrast to Lamboy, we see great promise fo r accurate phylogeny reconstruction using parsimony analysis of morpho logical data.