Abstract
Interspecific hybridization is a major mechanism for generating evolutionary novelty, as hybrid zones offer prime opportunities to explore processes that expand or reduce reproductive isolation. Hybridization between invading and resident fucoid species has been recently documented and may have significant evolutionary consequences for one or both species, as well as for community function more generally. Fucoid seaweeds are among the major structural species of rocky intertidal shores, are commercially exploited for a variety of products, and have been implicated as biodiversity indicators. Until now, hybrid zones in marine benthic species have focused exclusively on animals. The objectives of the proposed research are to: 1) Analyze the structure and dynamics of hybrid zones involving Fucus serratus x F. evanescens, using nuclear and organellar DNA polymorphisms (nuclear, mitochondrial and chloroplast markers); 2) Analyze the phylogeographic histories of these two species across Scandinavia (including Norway, Sweden, Denmark, Iceland and The Faeroes) by comparing gene genealogies based on cyto-nuclear marker comparisons; 3) Compare areas of old and recent sympatry of the two species; and 4) identify factors that maintain the hybrid zones.
Netherlands