HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Slaughter, C. Articles by Yund, P. O. Search for Related Content PubMed PubMed Citation Articles by Slaughter, C. Articles by Yund, P. O. Related Collections Ecology Evolution Insects Miscellaneous Invertebrates Miscellaneous Vertebrates Neuroscience

Comparison of Gamete Compatibility Between Two Blue Mussel Species in Sympatry and in Allopatry

Christin Slaughter^1,*, Michael A. McArtney^1, and Philip O. Yund²

¹ Department of Biological Sciences, Center for Marine Science, University of North Carolina at Wilmington, 5600 Marvin Moss Lane, Wilmington, North Carolina 28409
² Marine Science Center, University of New England, 11 Hills Beach Rd., Biddeford, Maine 04005

To whom correspondence should be addressed. E-mail: mccartneym{at}uncw.edu

Recent demonstrations of positive selection on genes controlling gamete compatibility have resulted in a proliferation of hypotheses concerning the sources of selection. We tested a prediction of one prominent hypothesis, selection to avoid hybridization (i.e., reinforcement), by comparing heterospecific gamete compatibility in two Mytilus edulis populations: one population in Cobscook Bay, Maine, in which the close congener, M. trossulus, is abundant (a region of sympatry), and one population in Kittery, Maine, in which M. trossulus is absent (a region of allopatry). Three diagnostic nuclear DNA markers were used to identify mussels to species and to estimate the frequency of both species and their hybrids in the two populations. Controlled crosses were then conducted by combining eggs of M. edulis females with a range of M.edulis and M. trossulus sperm concentrations. Results were not consistent with the reinforcement hypothesis. M. edulis females collected from the region of sympatry were no more incompatible with M. trossulus males than were M. edulis females collected from the region of allopatry. A trend in the opposite direction, toward greater compatibility in sympatry, suggests that introgression of M. trossulus genes that control egg compatibility, such as those encoding receptors for sperm, may influence evolution of gametic isolation in hybridizing populations.