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Saving the stem group—a contradiction in terms?

Published online by Cambridge University Press:  08 April 2016

Philip C. J. Donoghue*
Department of Earth Sciences, University of Bristol, Wills Memorial Building, Queens Road, Bristol BS8 1RJ, United Kingdom. 〈E-mail:〉


The classification of fossils has long been controversial. Should traditional taxonomic concepts be expanded to encompass plesiomorphic extinct relatives that exhibit subsets of essential defining characters in so many shades of gray? Should rank taxa, established on extant taxa alone, and in a pre-Darwinian, pre-Hennigian framework, remain restricted to their living constituents and integral extinct relatives? Or should these taxonomic concepts be restricted to a membership exhibiting a defining suite of essential characters, regardless of whether they are extant or extinct?

Matters of the Record
Copyright © The Paleontological Society 

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