Interrelationships of basal synapsids: cranial and postcranial morphological partitions suggest different topologies

  title={Interrelationships of basal synapsids: cranial and postcranial morphological partitions suggest different topologies},
  author={Roger B. J. Benson},
  journal={Journal of Systematic Palaeontology},
  pages={601 - 624}
  • R. Benson
  • Published 1 December 2012
  • Biology
  • Journal of Systematic Palaeontology
Basal synapsids (‘pelycosaurs’) form the basalmost portion of the mammalian stem lineage and document the transition from primitive ‘reptile-like’ basal amniotes to derived, mammal-like therapsids. They dominated terrestrial ecosystems of the latest Carboniferous and Early Permian (∼300–271 million years ago), producing large-bodied terrestrial animals (3–6.5 metres long), high-fibre herbivores, and macropredators for the first time in vertebrate history, alongside an array of smaller-bodied… 

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