Wits Evolutionary Studies Institute (ESI)

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Author: search.filters.author.Gow, Chris E.

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    First record of Eunotosaurus (Amniota: Parareptilia) from the Eastern Cape.
    (Bernard Price Institute for Palaeontological Research, 1997) Gow, Chris E.; de Klerk, Billy
    Eunotosaurus is a rare tetrapod fossil until recently known only from the Tapinocephaluszone of the main Karoo basin of Cape Province. A single specimen has recently been collected in the Free State (Weiman, pers. com.). This paper describes a new find from the Eastern Cape, where outcrops of Karoo rocks are scarce. The new specimen adds previously unknown morphological detail, particularly about the limbs. Phylogenetic affinities are clearly with the Parareptilia. particularly about the limbs. Phy logene tic affinities are clearly with the Parareptilia.
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    A reassessment of Eunotosaurus africanus Seeley (Amniota: Parareptilia).
    (Bernard Price Institute for Palaeontological Research, 1997) Gow, Chris E.
    This paper provides an almost complete description of the Permian fossil reptile Eunotosaurus for the first time. Taphonomy indicates that these were terrestrial animals; dentition suggests that they preyed on small invertebrates; while the broad, imbricating ribs point to a slow moving animal with a protective, turtle-like carapace. Temporal emargination and the fan-like iliac blade serve to align these animals with Parareptilia, sensu Laurin and Reisz ( 1995). Eunorosaurusand millerettids are sister taxa on the basis of s tapes and rib morphology, and together they constitute the sister taxon to Ankyramopha (Debraga and Reisz 1996), having eight characters in which they are less derived than the latter.
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    The oldest Procolophonoid (Amniota: Parareptilia) - New discovery from the lower Beaufort of South Africa.
    (Bernard Price Institute for Palaeontological Research, 1997) Gow, Chris E.; Rubidge, Bruce S.
    Until now the earliest recognised procolophonoid (sensu Laurin & Reisz 1995) reptile has been Owenetta, which ranges from the Cistecephalus assemblage zone (Upper Permian) to the Lystrosaurus assemblage zone (Lower Triassic) of the Beaufort Group of South Africa. This paper records the presence of a new even older form from low in the underlying Tapinocephalus assemblage zone.
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    A note on the postcranial skeleton of Milleretta (Amniota: Parareptilia).
    (Bernard Price Institute for Palaeontological Research, 1997) Gow, Chris E.
    This description of a partial postcranial skeleton of a mature individual of Milleretta rubidgei shows that it has very broad (laterally expanded) ribs, and growth of limb bones had ceased. Previously the only described postcranial skeleton was that of a young individual in which the ribs are not as broad and the ends of the limb bones were still formed of cartilage.
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    The importance of Karoo fossils in the search for mammal origins.
    (Bernard Price Institute for Palaeontological Research, 1997) Gow, Chris E.
    It has long been known that mammals belong to the group Synapsida (more familiar to most in South Africa by the now discredited term Mammal-like Reptiles), a group with a long fossil history, much of which was first established from the Karoo. In palaeontology mammals are traditionally defmed by the possession of a squamosal/dentary jaw joint, as opposed to the quadrate/articular jaw joint of non-mammalian tetrapods. This paper recounts some of the advances in our knowledge of the therapsids (advanced synapsids) over the past 50 years, including the discovery of a sequence offorms leading to those which possess both premammalian and mammalianjaw hinges, transitional forms which thus by defInition qualify as mammals. Briefmention is made of some historical aspects of phylogenetic interpretation, pointing out that some early workers following Darwin, were as aware of the central role of species in phylogenetics as are the disciples of Hennig and Eldredge and Gould. Briefreference is made to the crown group defmition of mammals proposed by Rowe (1988), as it contrasts with the traditional character-based definition. Finally, it is encouraging that modem workers are not only as aware of the problems of distinguishing homology and homoplasy as were earlier workers, but are starting to acknowledge the importance of missing information. In this way, just as the double jaw joint was first predicted and then found, we can actively seek to fill some of the many remaining gaps in our knowledge.