Nocturnality in synapsids predates the origin of mammals by over 100 million years

  title={Nocturnality in synapsids predates the origin of mammals by over 100 million years},
  author={Kenneth D. Angielczyk and Lars Schmitz},
  journal={Proceedings of the Royal Society B: Biological Sciences},
  • K. AngielczykL. Schmitz
  • Published 22 October 2014
  • Biology, Environmental Science, Geography
  • Proceedings of the Royal Society B: Biological Sciences
Nocturnality is widespread among extant mammals and often considered the ancestral behavioural pattern for all mammals. However, mammals are nested within a larger clade, Synapsida, and non-mammalian synapsids comprise a rich phylogenetic, morphological and ecological diversity. Even though non-mammalian synapsids potentially could elucidate the early evolution of diel activity patterns and enrich the understanding of synapsid palaeobiology, data on their diel activity are currently unavailable… 

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