A fossil‐calibrated relaxed clock for Ephedra indicates an Oligocene age for the divergence of Asian and New World clades and Miocene dispersal into South America

  title={A fossil‐calibrated relaxed clock for Ephedra indicates an Oligocene age for the divergence of Asian and New World clades and Miocene dispersal into South America},
  author={Stefanie M. Ickert‐Bond and Catarina Rydin and Susanne S. Renner},
  journal={Journal of Systematics and Evolution},
Abstract  Ephedra comprises approximately 50 species, which are roughly equally distributed between the Old and New World deserts, but not in the intervening regions (amphitropical range). Great heterogeneity in the substitution rates of Gnetales (Ephedra, Gnetum, and Welwitschia) has made it difficult to infer the ages of the major divergence events in Ephedra, such as the timing of the Beringian disjunction in the genus and the entry into South America. Here, we use data from as many Gnetales… 
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  • C. Hughes, R. Eastwood
  • Environmental Science, Biology
    Proceedings of the National Academy of Sciences
  • 2006
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