The origin and early diversification of tetrapods

  title={The origin and early diversification of tetrapods},
  author={Per Erik Ahlberg and Andrew R C Milner},
A series of new fossil discoveries, coupled with cladistic analysis of old and new data, is beginning to resolve the origin of tetrapods into a documented sequence of character acquisition. Devonian tetrapods were more fish-like than believed previously, whereas Lower Carboniferous tetrapod faunas contain early representatives of the amphibian and amniote lineages. These very different assemblages are separated by a 20-million-year Tournaisian gap' which has yielded very few tetrapod fossils. 
Tetrapod phylogeny, amphibian origins, and the definition of the name tetrapoda.
The most detailed, computer-generated phylogeny of early amphibians has been published recently, but the views Anderson expressed about the polyphyletic origin of extant amphibians and about the application of phylogenetic nomenclature are problematic.
Palaeontology: First Devonian tetrapod from Asia
The discovery of the first Devonian tetrapod from Asia is reported, a finding that substantially extends the geographical range of these animals and raises new questions about their dispersal.
A Devonian Tetrapod from North America
An early tetrapod fossil from the Upper Devonian of Pennsylvania (Catskill Formation) extends the temporal range of tetrapods in North America and suggests that they attained a virtually global
Palaeogeography: Devonian tetrapod from western Europe
A tetrapod jaw of about 365 million years old from the Famennian of Belgium is described, which is the first from western continental Europe and provides information about the conditions that prevailed just before the virtual disappearance of tetrapods from the fossil record for 20 Myr.
Early tetrapod evolution.
  • Coates, Ruta, Milner
  • Environmental Science, Biology
    Trends in ecology & evolution
  • 2000
Early Carboniferous tetrapods in Australia
The Drummond basin fauna indicates that several major groups of tetrapods were distributed worldwide through equatorial regions during the Early Carboniferous, and represents groups previously confined to Europe and North America.
Bones, molecules, and crown- tetrapod origins
The timing of major events in the evolutionary history of early tetrapods is discussed in the light of a new cladistic analysis. The phylogenetic implications of this are compared with those of the
An amniote-like skeleton from the Early Carboniferous of Scotland
A small, highly ossified, postcranial skeleton of a terrestrially adapted, amniote-like tetrapod from the Mid Viséan is reported, which shows the earliest known pentadactyl manus and pushes back the known occurrence of terrestrial vertebrates closer to the origin of tetrapods.
Ontogenetic evidence for the Paleozoic ancestry of salamanders
Comparison of patterns of larval development in Paleozoic and modern amphibians provides a means to test previous phylogenies based primarily on adult characteristics and proves to be highly informative in the case of the origin of salamanders.


A recent review by Rosen et al. (1981) claims that Dipnoi (lungfish) are the sister‐group of the Tetrapoda, that Osteolepiformes is a non‐taxon and that Eusthenopteron is more distant from tetrapods than are Dip noi, coelacanths and probably the fossil Porole piformes, are refuted by use of the same cladistic technique.
The Relationships of the Modern Amphibia: A Re-Examination
Evidence is presented supporting the viewpoint that all the moderns Amphibia are clearly related. It is suggested that the three living orders constitute a natural monophyletic group-the infra-class
A primitive amphibian from the Late Devonian of New South Wales
The musculatures of rhipidistian and amphibian jaws are analysed and are shown to be functionally related to distinctive morphologies of the articulatory region in each group, Metaxygnathus being of amphibian type.
A new Lower Carboniferous tetrapod locality in Iowa
The earliest tetrapods known are from two or three Upper Devonian1–3 and some 20 Lower Carboniferous localities in Scotland4 and North America5–8. Most sites yield few and fragmentary specimens;
Westlothiana gen. nov.: naming the earliest known reptile
This is the most primitive known reptile and establishes the presence in the Lower Carboniferous of a reptile fauna sufficiently ancient to have been ancestral to all later amniotes.
The oldest microsaur (Amphibia)
Utaherpeton franklini n. gen. and sp., from the Manning Canyon Shale Formation of Utah, is the oldest known microsaur. The horizon is dated as equivalent to the lowermost Namurian B of Europe
New Palaeontological Contributions to Limb Ontogeny and Phylogeny
An updated palaeontological data–base is provided for the study of vertebrate limb development to produce an almost completely new picture of the emergence of terrestrial vertebrate life.
The Primary Radiation of Terrestrial Vertebrates
There is a rich record of osteolepiform fish in the Late Devonian and throughout the Carboniferous, but no fossils are known that can be considered intermediate between these clearly aquatic fish and genera that are unequivocally classified as ter­ restrial vertebrates.
The earliest known reptile
The discovery of a much earlier amniote skeleton from the Brigantian (Lower Carboniferous) of Scotland, which thus represents the earliest occurrence of amniotes in the fossil record.
Trackways of Tetrapod Vertebrates from the Upper Devonian of Victoria, Australia
THREE distinct trackways of tetrapod vertebrates were discovered late in 1971 by one of us (N. A. W.) in strata of the Genoa River Beds at lat. 37° 19′ S, long. 149° 23′ E, in eastern Victoria,