Climate Oscillations, Range Shifts and Phylogeographic Patterns of North Atlantic Fucaceae

• Main Authors: Neiva, João, Serrão, Ester A., Assis, Jorge, Pearson, Gareth A., Coyer, James, Olsen, Jeanine, Hoarau, Galice, Valero, Myriam
• Other Authors: Hu, Zi-Min, Fraser, Ceridwen
• Format: Book Part
• Language: English
• Published: Springer 2016
• Subjects: North-Atlantic intertidal; Climatic refugia; COMPARATIVE PHYLOGEOGRAPHY; fucoid seaweeds; genetic diversity; latitudinal range shifts; marine introductions; glacial-interglacial cycles; ongoing climate change; pathways of range expansion; rafting; restricted dispersal; North Atlantic; North East Atlantic; North West Atlantic
• Online Access: https://hdl.handle.net/11370/56df5d6b-747c-43fa-8b5e-725bb5dfe425; https://research.rug.nl/en/publications/56df5d6b-747c-43fa-8b5e-725bb5dfe425; https://doi.org/10.1007/978-94-017-7534-2_11

Members of the seaweed family Fucaceae have been recurrent models in North Atlantic phylogeographic research; numerous studies have been published since 2000, and this review synthesizes their major findings. Fucoid species exhibited diverse responses to glacial–interglacial cycles, but evidence indicates there were a few common refugial areas such as north-western Iberia, the Celtic Sea (Brittany/Ireland) region and the North-west Atlantic. In genetically rich refugial areas, pervasive genetic breaks confirmed presently limited gene flow between adjacent distinct genetic groups. In contrast with the maintenance of sharp genetic breaks, most species experienced extensive migration during post-glacial expansion. Poleward migrations in the North-east Atlantic followed routes along north-western Ireland and the transgressing English Channel. These patterns support the role of density-blocking in maintaining sharp genetic breaks at contact zones, and of long-distance dispersal from range edges in mediating expansion into uninhabited regions. The data also indicate that expansions involve mostly the genetic groups located at range edges rather than the entire species’ gene pool, both poleward during interglacials and toward warmer regions during glacial periods. Fucoid expansions have also been linked to introgressive recombination of genomes at (and beyond) contact zones and to gene surfing leading to present large-scale dominance by alleles that were located at the expanding edge. Phylogeographic approaches have also proven useful to identify and track the sources of introductions linked to marine traffic. The integration of environmental niche models with molecular data have further allowed hindcasting southern distributions during glaciation and predicting the potentially negative effects of future climate warming, including the loss of vulnerable, unique trailing-edge lineages, as species’ ranges are predicted to continue shifting northward. Collectively, these studies have contributed greatly to elucidating the ...