Dates, nodes and character conflict: Addressing the Lissamphibian origin problem

By M. Ruta, Michael I. Coates. 2007

213 citations recorded by the source corpus.

Synopsis Extant amphibians consist of Salientia (frogs), Caudata (salamanders), and Gymnophiona (caecilians). The mutual relationships of these groups are controversial, with either Batrachia (Salientia + Caudata) or Procera (Gymnophiona + Caudata) as emerging clades in recent molecular and morphological analyses. The monophyly of amphibians as a whole is supported by independent data, but their origins and affinities with early tetrapods are debated. A new cladistic analysis of early tetrapods retrieves Temnospondyli (the most species‐rich group of early tetrapods) as the closest relatives of crown group amphibians. One temnospondyl group, the Dissorophoidea, forms a series of consecutive outgroups to crown amphibians. In particular, the Lower Permian amphibamid Doleserpeton is the most derived plesion on the amphibian stem. The Albanerpetontidae, a group of salamander‐like tetrapods ranging from the Jurassic to the Pliocene, are placed as stem Gymnophiona. The shortest trees support the Batrachia hypothesis. However, the Procera hypothesis is not a significantly worse fit for the whole character set. Exhaustive treatment of characters and taxa is the most appropriate way to disentangle contrasting phylogenetic signals in large matrices. Tests of different crown topologies show that placement of amphibians within lepospondyls (e.g. as sister taxon to Lysorophia) is not a significantly worse fit for the whole character set than a close temnospondyl‐lissamphibian relationship. However, the latter phylogenetic hypothesis best captures the most coherent assembly of derived lissamphibian apomorphies.

Subfields: Global and Planetary Change, Nature and Landscape Conservation, Paleontology

View Paper: https://www.semanticscholar.org/paper/9ca555236bca6223d16f16ae17f76bbd2cde6f4d

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Global and Planetary Change

1. Michel Laurin
2. D. Marjanović
3. R. Schoch
4. Michael Benton
5. M. Friedman
6. J. Bolt
7. T. Sigurdsen

In Nature and Landscape Conservation

1. Michel Laurin
2. D. Marjanović
3. R. Schoch
4. M. Friedman
5. J. Bolt
6. T. Sigurdsen
7. Michael Benton
8. T. Near

In Paleontology

1. Michel Laurin
2. D. Marjanović
3. R. Schoch
4. M. Friedman
5. J. Bolt
6. T. Sigurdsen
7. Michael Benton
8. T. Near

Citations in the corpus

• Ever Since Owen: Changing Perspectives on the Early Evolution of Tetrapods (2008, background): “More recent analyses have presented a somewhat different phylogenetic structure (Ruta & Coates 2007, Ruta et al. 2003) in which most Carboniferous limbed tetrapods are included within the crown.”
• The Lower Permian Amphibamid Doleserpeton (Temnospondyli: Dissorophoidea), The Interrelationships of Amphibamids, and the Origin of Modern Amphibians (2010, background): “There is at present no consensus as to whether amphibamids constitute the sister group of all modern amphibians (e.g., Ruta and Coates, 2007), of parts thereof (e.g., Anderson, 2007; Carroll, 2007; Anderson et al., 2008b), or of none at all (e.g., Laurin and Reisz, 1997; Vallin and Laurin, 2004).”
• The evolution of major temnospondyl clades: an inclusive phylogenetic analysis (2013, background): “All recent studies agree that if batrachians or lissamphibians really are temnospondyls, then they nest within the most derived amphibamids (Ruta & Coates 2007; Anderson et al. 2008a; Sigurdsen & Bolt 2009).”
• The origin(s) of extant amphibians: a review with emphasis on the “lepospondyl hypothesis” (2013, methodology): “…(2012: 70) pointed out that the matrix of Vallin & Laurin (2004), which supports the LH, is considerably smaller than those which support the TH (Ruta et al. 2003; Ruta & Coates 2007) or some that support the PH (Anderson 2007; Anderson et al. 2008b) and used this as an argument against the LH.”
• Constraints on the timescale of animal evolutionary history (2015, background): “Triadobatrachus has always been recognised as basal member of Anura, within the stem Batrachia, and so the oldest member of the crown Batrachia, based on its possession of the key apomorphies of a posteriorly open maxillary arcade, absence of an ossified postparietal, tabular, jugal, quadratojugal, ”
• FINS INTO LIMBS: EVOLUTION, DEVELOPMENT AND TRANSFORMATION (2007, background): “…the few computerassisted analyses that include a taxonomic sampling adequate to test extant amphibian origins, the only one in which lissamphibians are nested within temnospondyls (the study by Ruta and Coates, 2007, finds the same result, but was obviously published too late to be considered).”