The Origin(s) of Modern Amphibians: A Commentary
- 415 Downloads
Anderson (2008) recently reviewed the controversial topic of extant amphibian origins, on which three (groups of) hypotheses exist at the moment. Anderson favors the “polyphyly hypothesis” (PH), which considers the extant amphibians to be polyphyletic with respect to many Paleozoic limbed vertebrates and was most recently supported by the analysis of Anderson et al. (2008). Another is the “temnospondyl hypothesis” (TH—lissamphibians nested within temnospondyls), most recently supported by Ruta and Coates (2007). We prefer the “lepospondyl hypothesis” (LH—lissamphibians nested within “lepospondyls”; most recently supported by Vallin and Laurin 2004 and Marjanović and Laurin 2008a). We would like to clarify important points that were not discussed in Anderson’s review, or for which crucial arguments were left out.
Anderson (2008) argues that most molecular dates favor the PH because they suggest a Devonian or Early Carboniferous diversification of Lissamphibia. This is inaccurate, since...
KeywordsPhylogenetic Signal Loss Character Stratigraphic Range Multistate Character Laurin
J.-C. Rage, D. Wake, and two anonymous referees commented on previous drafts of this paper; we are especially grateful to D. Wake for several constructive suggestions.
- Bossy, K. A., & Milner, A. C. (1998). Order Nectridea Miall 1875. Carroll, R. L., Bossy, K. A., Milner, A. C., Andrews, S. M., & Wellstead, C. F. In P. Wellnhofer (Ed.), Encyclopedia of Paleoherpetology, Part 1: Lepospondyli (pp. 73–131). Munich: Dr. Friedrich Pfeil.Google Scholar
- Germain D. (2008a). Anatomie des Lépospondyles et origine des Lissamphibiens (PhD thesis, Muséum National d’Histoire Naturelle, Paris) 351 pp.Google Scholar
- Germain, D. (2008b). A new phlegethontiid specimen (Lepospondyli, Aistopoda) from the Late Carboniferous of Montceau-les-Mines (Saône-et-Loire, France). Geodiversitas, 30, 669–680.Google Scholar
- Marjanović, D., & Laurin, M. (2008a). A reevaluation of the evidence supporting an unorthodox hypothesis on the origin of extant amphibians. Contributions to Zoology, 77, 149–199.Google Scholar
- Milner, A. C. (1980). A review of the Nectridea (Amphibia). In A. L. Panchen (Ed.), The terrestrial environment and the origin of land vertebrates (pp. 377–405). London and New York: Academic Press.Google Scholar
- Pawley K. (2006). The postcranial skeleton of temnospondyls (Tetrapoda: Temnospondyli) (PhD thesis, La Trobe University, Melbourne), 442 pp. Retrieved from http://www.lib.latrobe.edu.au/thesis/public/adt-LTU20061124.124055/index.html.
- Schoch, R. R. (1992). Comparative ontogeny of Early Permian branchiosaurid amphibians from southwestern Germany. Palaeontographica. Abteilung A, 222, 43–83.Google Scholar
- Schoch, R. R., & Milner, A. R. (2004). Structure and implications of theories on the origin of lissamphibians. In G. Arratia, M. V. H. Wilson, & R. Cloutier (Eds.), Recent advances in the origin and early radiations of vertebrates (pp. 345–377). Munich: Dr. Friedrich Pfeil.Google Scholar