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Excerpt from Compositae Newsletter: December, 1994 In Anderberg's analyses, approximately half of the scored Gnaphalieae taxa were excluded from the first analysis, then partitioned into the various clades resolved by that analysis, for subsequent detailed analyses of those clades. This strategy is sensible, since it reduces the numbers of taxa in each analysis, allowing heuristic algorithms a better chance of finding a minimal solution. However, the assumptions on which this exclusion and partitioning process are based need to be explicit and tested: in Anderberg's analyses, they were neither. The most important assumption made by Anderberg is that the clades discovered in the first analysis remained monophyletic after the extra taxa had been partitioned into them. That is, the extra taxa should share the synapomorphies on which the clade is based. However, Anderberg's first analysis produced low consistency and retention indices and respectively). This is evidence that considerable homoplasy exists in the data, a result that is to be expected for large morphological data sets (sanderson Donoghue However, it casts doubt on the ability to find suitable homes for the excluded taxa few if any unequivocal synapomorphies are available for defining the main clades, so few unequivocal placements of the excluded taxa can be made on the basis of synapomorphy. Instead, Anderberg relied on intuitive, non-explicit assessments of relationships of the excluded to included taxa. He may have been right, of course, but the large advantages of cladistic methodology are its rigour and explicitness, and these were severely compromised in his analysis by this step. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whil