Loading ...
Sorry, an error occurred while loading the content.

end-Devonian extinction & bottleneck in evolutionary history of jawed vertebrates

Expand Messages
  • Stephan Pickering
    Lauren Cole Sallan & M.I. Coates, 2010. End-Devonian extinction and a bottleneck in the early evolution of modern jawed vertebrates. Proc. National Academy of
    Message 1 of 1 , Jun 1, 2010
    • 0 Attachment
      Lauren Cole Sallan & M.I. Coates, 2010. End-Devonian extinction and a bottleneck in the early evolution of modern jawed vertebrates. Proc. National Academy of Sciences 107(22):10131-10135 + Supporting Information [Appendix (PDF), Datasets S01-02 (XLS)]. ABSTRACT. The Devonian marks a critical stage in the early evolution of vertebrates: It opens with an unprecedented diversity of fishes, and closes with the earliest evidence of limbed tetrapods. However, the latter part of the Devonian has also been characterized as a period of global biotic crisis marked by two large extinction pulses: a “Big Five” mass extinction event at the Frasnian-Famennian stage boundary (374 Ma), and the less well-documented Hangenberg event some 15 million years later at the Devonian-Carboniferous boundary (359 Ma). Here, we report the results of a wide-ranging analysis of the impact of these events on early vertebrate evolution, which was obtained from a database of vertebrate occurrences sampling over 1,250 taxa from 66 localities spanning Givetian to Serpukhovian stages (391 to 318 Ma). We show that major vertebrate clades suffered acute and systematic effects centered on the Hangenberg extinction involving long-term losses of over 50% of diversity, and the restructuring of vertebrate ecosystems worldwide. Marine and nonmarine faunas were equally affected, precluding the existence of environmental refugia. The subsequent recovery of previously diverse groups (including placoderms, sarcopterygian fish, and acanthodians) was minimal. Tetrapods, actinopterygians, and chondrichthyans, all scarce within the Devonian, undergo large diversification events in the aftermath of the extinction, dominating all subsequent faunas. The Hangenberg event represents a previously unrecognized bottleneck in the evolutionary history of vertebrates as a whole, and a historical contingency that shaped the roots of modern biodiversity.
      STEPHAN PICKERING / Chofetz Chayim ben-Avraham
      Jewish dinosaurologist / Heretic spiritist
      2333 Portola Drive # 4
      Santa Cruz, California 95062-4250
      IN PROGRESS: Mutanda Dinosaurologica: in memory of Samuel Paul Welles (9 November 1909--6 August 1997)
      IN PROGRESS: Dialects of a synaesthetic heart: poetics for Faline Pickering (23 January 1949--24 August 2008)
      IN PROGRESS: Alfred Russel Wallace's KING KONG: the semioptics of Willis O'Brien
      MEMBER 13853: Society of Vertebrate Paleontology
      One concept corrupts and confuses the others. I am not speaking of the Evil whose limited sphere is ethics; I am speaking of the infinite. -- J.L. BORGES
      You never know what's comin' for you. -- QUEENIE in ERIC ROTH'S  The curious case of Benjamin Button
      What if G-d didn't say it? -- BART EHRMAN
      Seek the sacred with the ordinary. Seek the remarkable with the commonplace. -- REB NACHMAN OF BRATSLAV
      G-d is all that exists, but not all that exists is G-d. -- R. MOSHE CORDOVERO

    Your message has been successfully submitted and would be delivered to recipients shortly.