The Tree Squirrel Sciurus (Sciuridae, Rodentia) as a Living Fossil

  • Robert J. Emry
  • Richard W. ThoringtonJr.
Part of the Casebooks in Earth Sciences book series (CASEBOOKS)


The familiar living squirrel, Sciurus, is not among the classic and often-cited examples of living fossils, although squirrels have long been recognized as being among the most primitive members of the Rodentia, the mammalian order that has exceeded all others in specific diversity. In the sense that they represent the least derived family of a very diverse order, squirrels in general might be called living fossils. The recently discovered skeleton of Protosciurus (perhaps the oldest squirrel fossil) shows that the earliest recognized sciurid is strikingly similar in its osteology to living Sciurus. In the sense that it has evolved very little from what is apparently the primitive squirrel morphotype, Sciurus is a living fossil.


Ground Squirrel Cheek Tooth Gray Squirrel Tree Squirrel Serotinous Cone 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag New York Inc. 1984

Authors and Affiliations

  • Robert J. Emry
    • 1
    • 2
  • Richard W. ThoringtonJr.
    • 1
    • 2
  1. 1.Department of Paleobiology, Smithsonian InstitutionNational Museum of Natural HistoryUSA
  2. 2.Department of Vertebrate Zoology, Smithsonian InstitutionNational Museum of Natural HistoryUSA

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