Nirav Patel
4/12/2011
Biogeography
Very interesting, and a good report.
10/10
1. Coyer, J. A., Hoarau, G., Van Schaik, J., Luijckx, P., Olsen, J.L. 2011. Trans-Pacific and
trans-Arctic pathways of the intertidal macroalga Fucus distichus L. reveal multiple glacial
refugia and colonizations from the North Pacific to the North Atlantic. Journal of Biogeography
(J.Biogeogr.) (2011) 38, 756-771.
James A. Coyer is with the Department of Marine Benthic Ecology and Evolution, Center for
Ecological and Evolutionary Studies, University of Groningen, Center for Life Sciences,
Nijenborgh 7, 9747 AG Groningen, The Netherlands
Galice Hoarau is part of the Marine Ecology Group, Faculty of Biosciences and Aquaculture,
Bodo, Norway, University of Basel, in Basel, Switzerland.
2). Of the species of the brown algal genus Fucus, F. distichus is particularly abundant in the
North Pacific and the North Atlantic. Can the analysis of the algae shed light on the
phylogeographic history within and between the oceans in response to the trans-Arctic
expansion?
3. F. distichus was particularly selected for the reason that it is extremely abundant in the North
Pacific and the North Atlantic and because the algae is not phylogenically different from other
alga. What the researchers want to learn about is the multiple opening and closing cycles that
marked the trans-Arctic marine connection that has shaped the phylogeographical patterns of
marine and terrestrial species found in the Northern Hemisphere. The study of the brown algal
genus Fucus is in aims of shedding light on how this period impacted this genus’s
phylogeographic history.
4) Selected individuals from 23 populations for mitochondrial DNA intergenic spacer (n=608)
and used the cytochrome c oxidase subunit I region (n=276), as well as six nuclear microsatellite
loci (n=592). This structure and connectivity was assessd using population genetic and other
network analyses.
5) IGS and COI haplotype diversity was very high. IGC being highest in North Pacific, and
divergence there was older in comparison to Atlantic. Ancestral IGS/COI clusters led to Atlantic
cluster. Also noted was the high diversity levels close to Prince William Sound, even after the
1989 Exxon Valdez oil spill.
Nirav Patel
4/12/2011
Biogeography
Nirav Patel
4/12/2011
Biogeography
6) The use of the algal genus Fucus could be debated along with the discussion of dispersal, but
at the same time this is the only species we can utilize useable and meaningful data.
7) The movement of this algal genus was confirmed for two colonizations from the North Pacific
populations to the North Atlantic, between the period of the opening of the Bering Strait to the
last glacial maximum. It was also noted that the presence of two haplotypes in the central
Atlantic shows that these oceans are too warm to now support F. distichus. As ice cover
decreases in the Arctic, it is argued that the North Pacific and North Atlantic populations will
interact with each other again.