autapomorphy

noun au·tap·o·mor·phy \ ȯ-ˈta-pə-ˌmȯr-fē \

Definition of autapomorphy

plural autapomorphies
biological taxonomy
:a specialized character or trait that is unique to a monophyletic taxonomic group
  • … An eversible penis is a synapomorphy that unites lizards and snakes in a common monophyletic group, the Squamata, but is an autapomorphy of the Squamata within a larger monophyletic assemblage.
  • —Robert L. CarrollPatterns and Processes in Vertebrate Evolution1997
  • These species share key traits as autapomorphies of their clade—and since these traits help to construct the relevant environment, sufficient similarity becomes, in part, an active construction of related organisms, not only a happenstance of common externalities.
  • —Stephen Jay GouldThe Structure of Evolutionary Theory2002

autapomorphic

play \ȯ-ˌta-pə-ˈmȯr-fik\ or less commonly autapomorph play \ȯ-ˈta-pə-ˌmȯrf\ adjective
    • These features are not known for any Jurassic and Cretaceous mammals and are autapomorphic for this new mammalian lineage.
    • —Zhe-Xi Luo and John R. WibleScience1 Apr. 2005

autapomorphous

play \ȯ-ˌta-pə-ˈmȯr-fəs\ adjective
    • The Chondrichthyes are a monophyletic clade and are principally distinguished on the basis of two unique autapomorphous character sets.
    • —Eileen D. Grogan and Richard Lund, in Biology of Sharks and their Relatives2004

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Origin and Etymology of autapomorphy

autapomorph (borrowed from German, from aut-aut- + apomorph “apomorphic”) +2-y


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