Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Sexton, P. F. Articles by Norris, R. D. Search for Related Content GeoRef GeoRef Citation

Dispersal and biogeography of marine plankton: Long-distance dispersal of the foraminifer Truncorotalia truncatulinoides

^{1 1}National Oceanography Centre, University of Southampton, European Way, Southampton, SO14 3ZH, UK
^{2 2}Scripps Institution of Oceanography, University of California–San Diego, La Jolla, California 92093-0244, USA

Speciation models for marine plankton commonly assume that tectonic barriers and water mass fronts act as potent isolating mechanisms. Here we present evidence indicating that tectonic and water mass barriers to dispersal are, in some cases, very weak. We identify a transient occurrence (19 k.y. duration) of the planktic foraminifer Truncorotalia truncatulinoides in the Atlantic Ocean 500 k.y. before its generally accepted first appearance anywhere outside the southwest Pacific. This finding provides strong evidence for long-distance dispersal of plankton, enabling them to opportunistically colonize normally inhospitable environments as soon as they become favorable. Our newly described appearances of T. truncatulinoides in the Atlantic are restricted to the onset of the first very severe glacial stage (marine isotope stage 100) at 2.54 Ma, ~200 k.y. after the global evolution of the species in the southwest Pacific. This ability of plankton to disperse long distances, combined with recent evidence for high gene flow throughout the extra-polar oceans, suggests that it may be very difficult, even impossible, to geographically isolate pelagic populations for extended periods of time, a key component in vicariant and allopatric speciation models. Instead, high dispersal capability favors sympatric or parapatric processes as the prevalent modes of marine speciation.

This article has been cited by other articles:

				P. Cermeno and P. G. Falkowski Controls on Diatom Biogeography in the Ocean Science, September 18, 2009; 325(5947): 1539 - 1541. [Abstract] [Full Text] [PDF]