Focal Review: The Origin(s) of Modern Amphibians

@article{Anderson2008FocalRT,
  title={Focal Review: The Origin(s) of Modern Amphibians},
  author={Jason S. Anderson},
  journal={Evolutionary Biology},
  year={2008},
  volume={35},
  pages={231-247}
}
  • Jason S. Anderson
  • Published 12 November 2008
  • Biology, Environmental Science
  • Evolutionary Biology
The recent description of the stem batrachian Gerobatrachus has changed the terms of the ongoing debate on the origin of extant amphibians (Lissamphibia: frogs, salamanders, and the limbless caecilians). This important fossil, through a shared mosaic of unique derived salientian and urodele characters, links frogs and salamanders with an archaic group of fossil amphibians known as amphibamid temnospondyls. The present paper reviews the impact of this fossil on morphological and molecular… 

The origin of modern amphibians: a re-evaluation

TLDR
A matrix based on data from all three hypotheses and analysed key taxa phylogenetically using both Bayesian inference and parsimony supported the temnospondyl hypothesis of lissamphibian origins.

A multilocus timescale for the origin of extant amphibians.

The lower permian dissorophoid «doleserpeton» (temnospondyli), and the evolution of modern amphibians

The origin and evolution of modern amphibians is still a subject of controversy. The amphibamid temnospondyl Doleserpeton has often been suggested as a close relative of modern amphibians, but the

A New Amphibamid (Temnospondyli: Dissorophoidea) from the Early Permian of Texas

TLDR
A new genus and species of amphibamid, Rubeostratilia texensis, represented by a skull from the Early Permian of Texas, shows many similarities with a recent described species from Richards Spur, Oklahoma, Pasawioops mayi.

A Triassic stem-salamander from Kyrgyzstan and the origin of salamanders

TLDR
A new specimen of Triassurus sixtelae is reported, a hitherto enigmatic tetrapod from the Middle/Late Triassic of Kyrgyzstan, which is identified as the geologically oldest stem-group salamander, shedding light not only on the early evolution of the salamanders body plan, but also on the origin of the group as a whole.

The origin(s) of extant amphibians: a review with emphasis on the “lepospondyl hypothesis”

TLDR
It is proposed that the complex of characters called the salamander mode of autopodium development is (in its less extreme forms) plesiomorphic for limbed vertebrates, so the apparent presence of this mode of development in temnospondyls cannot support the TH or the PH.

The Origin(s) of Modern Amphibians: A Commentary

TLDR
Anderson (2008) argues that the LH is mainly supported by loss char-acters, and that this is problematic ‘’given the relative easethat these losses can arise via paedomorphosis, which appears to evolve repeatedly’’, and emphasizes develop-ment characters such as digit development and skull ossi-fication order, which are known to be homoplastic.

The putative lissamphibian stem-group: phylogeny and evolution of the dissorophoid temnospondyls

  • R. Schoch
  • Biology, Environmental Science
    Journal of Paleontology
  • 2018
TLDR
An inclusive phylogenetic analysis of dissorophoids gives new insights into the large-scale topology of relationships, including a basal dichotomy between the large, heavily ossified Olsoniformes and the small salamander-like Amphibamiformes.

An updated paleontological timetree of lissamphibians, with comments on the anatomy of Jurassic crown-group salamanders (Urodela)

TLDR
The conclusion that the fossil record of Lissamphibia is dense enough to provide reliable calibration constraints for molecular divergence dating is upheld and some of the divergence dates the authors infer from the tree are up to 15 Ma younger than previously published.

The Lower Permian Amphibamid Doleserpeton (Temnospondyli: Dissorophoidea), The Interrelationships of Amphibamids, and the Origin of Modern Amphibians

TLDR
Doleserpeton adds to the strong evidence for a temnospondyl origin of batrachians, particularly for anurans, and the hypothesis proposing a lepospondylorigin of modern amphibians is questioned.
...

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TLDR
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