How to use genetic data to distinguish between natural and human-mediated introduction of Littorina littorea to North America

Journal Article

The rapid range southward expansion of the periwinkle Littorina littorea from the Canadian maritimes has fueled a long-running debate over whether this species was introduced to North America by human activity. A reappraisal of the mitochondrial DNA sequence evidence finds considerable endemic allelic diversity in the American population. The degree of endemic genetic diversity is higher than expected from human-mediated colonization, but not so much to suggest that it survived the last glacial maximum in America. Coalescent estimates of population divergence agree that colonization of America preceded European contact. A reappraisal of the ITS nuclear sequence data finds extensive recombination. Taking this recombination into account strengthens the genetic case against human-mediated introduction. Finally, a reappraisal of conflicting allozyme studies from the 1970's supports a claim of limited divergence between American and European populations. This is consistent with post-glacial colonization, but the allozyme data cannot distinguish between natural or human-mediated colonization. Taken as a whole, the DNA sequence data supports the many sub-fossil reports of an American L. littorea population in the Canadian maritimes that preceded even the first visits by the Vikings. © 2007 Springer Science+Business Media, Inc.

Full Text

Duke Authors

Cited Authors

  • Cunningham, CW

Published Date

  • 2008

Published In

Volume / Issue

  • 10 / 1

Start / End Page

  • 1 - 6

International Standard Serial Number (ISSN)

  • 1387-3547

Digital Object Identifier (DOI)

  • 10.1007/s10530-007-9099-8