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Full-Text Articles in Animal Sciences
A Cladistic Analysis And Taxonomic Revision Of The Plesiosauria (Reptilia: Sauropterygia), F. Robin O’Keefe
A Cladistic Analysis And Taxonomic Revision Of The Plesiosauria (Reptilia: Sauropterygia), F. Robin O’Keefe
Biological Sciences Faculty Research
The Plesiosauria (Reptilia: Sauropterygia) is a group of Mesozoic marine reptiles known from abundant material, with specimens described from all continents. The group originated very near the Triassic–Jurassic boundary and persisted to the end- Cretaceous mass extinction. This study describes the results of a specimen-based cladistic study of the Plesiosauria, based on examination of 34 taxa scored for 166 morphological characters. The Pliosauroidea is found to by polyphyletic due to the inclusion of the Polycotylidae; this second clade is instead a member of the Plesiosauroidea, and thus more closely related to elasmosaurs than to other ‘pliosaurs’. Characters of body proportion …
Inferring And Testing Hypotheses Of Cladistic Character Dependence By Using Character Compatibility, F. Robin O’Keefe, Peter J. Wagner
Inferring And Testing Hypotheses Of Cladistic Character Dependence By Using Character Compatibility, F. Robin O’Keefe, Peter J. Wagner
Biological Sciences Faculty Research
The notion that two characters evolve independently is of interest for two reasons. First, theories of biological integration often predict that change in one character requires complementary change in another. Second, character independence is a basic assumption of most phylogenetic inference methods, and dependent characters might confound attempts at phylogenetic inference. Previously proposed tests of correlated character evolution require a model phylogeny and therefore assume that nonphylogenetic correlation has a negligible effect on initial tree construction. This paper develops “tree-free” methods for testing the independence of cladistic characters. These methods can test the character independence model as a hypothesis before …