Geologic drivers of late ordovician faunal change in laurentia: investigating links between tectonics, speciation, and biotic invasions

PLoS One. 2013 Jul 15;8(7):e68353. doi: 10.1371/journal.pone.0068353. Print 2013.

Abstract

Geologic process, including tectonics and global climate change, profoundly impact the evolution of life because they have the propensity to facilitate episodes of biogeographic differentiation and influence patterns of speciation. We investigate causal links between a dramatic faunal turnover and two dominant geologic processes operating within Laurentia during the Late Ordovician: the Taconian Orogeny and GICE related global cooling. We utilize a novel approach for elucidating the relationship between biotic and geologic changes using a time-stratigraphic, species-level evolutionary framework for articulated brachiopods from North America. Phylogenetic biogeographic analyses indicate a fundamental shift in speciation mode-from a vicariance to dispersal dominated macroevolutionary regime-across the boundary between the Sandbian to Katian Stages. This boundary also corresponds to the onset of renewed intensification of tectonic activity and mountain building, the development of an upwelling zone that introduced cool, nutrient-rich waters into the epieric seas of eastern Laurentia, and the GICE isotopic excursion. The synchronicity of these dramatic geologic, oceanographic, and macroevolutionary changes supports the influence of geologic events on biological evolution. Together, the renewed tectonic activity and oceanographic changes facilitated fundamental changes in habitat structure in eastern North America that reduced opportunities for isolation and vicariance. They also facilitated regional biotic dispersal of taxa that led to the subsequent establishment of extrabasinal (=invasive) species and may have led to a suppression of speciation within Laurentian faunas. Phylogenetic biogeographic analysis further indicates that the Richmondian Invasion was a multidirectional regional invasion event that involved taxa immigrating into the Cincinnati region from basins located near the continental margins and within the continental interior.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Biodiversity
  • Climate Change
  • Genetic Speciation*
  • Geological Phenomena*
  • Introduced Species*
  • Phylogeny*
  • Phylogeography
  • Population Dynamics

Grants and funding

This research was supported by NSF EAR-0922067 to ALS and the Schuchert and Dunbar Grants-in-Aid Award from the Yale Peabody Museum, the Dry Dredgers Paul Sanders Award, the Ohio University Geological Sciences Alumni Grant, and the OHIO Center for Ecology and Evolutionary Studies Fellowship to DFW. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.