[Coral-List] New publication on Indian Ocean evolutionary history (corals)

[dobura at cordioea.net]

Dear
Listers,


 



Posting
this new paper I’ve finally given birth to in J. Biogeography as it’s of
general biogeographic and evolutionary interest, and complements/completes an
earlier paper on present day biogeography.



 



Happy
reading!  David



 



 


J.
Biogeography – evolutionary history - http://onlinelibrary.wiley.com/doi/10.1111/jbi.12656/abstract



PLOS
ONE – present biogeography - http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0045013



 



 



Citation:
Obura, D. O. (2015), An Indian Ocean centre of origin revisited: Palaeogene and
Neogene influences defining a biogeographic realm. Journal of Biogeography.
doi: 10.1111/jbi.12656



 



Abstract



Aim



The
biogeography and origins of the shallow marine fauna in the western and
northern Indian Ocean are poorly known. Focusing on scleractinian corals, this
study synthesizes evidence from extant biogeographical patterns, phylogenetics,
plate tectonics and palaeoceanography to provide new support for a hypothesis
on an Indian Ocean ‘centre of origin’ for shallow marine taxa.



 



Location



The
western and northern Indian Ocean, from approximately 90°E westwards, including
the Red Sea and Arabian Sea.



 



Methods



Synthesis
of primary observations and published literature.



 



Results



Ten per
cent of western and northern Indian Ocean coral species are endemic, with the
genera Acropora, Anomastrea, Coscinaraea, Craterastrea, Ctenella, Gyrosmilia,
Horastrea, Sclerophyllia, Siderastrea and Stylophora presenting evidence for
deep and shallow evolutionary origins unique to the region. Evidence for
origins in the Eocene Tethys Sea and Oligocene East Africa-Arabian Province,
the global hotspots of shallow tropical marine biodiversity in their time, is
derived from the fossil record, clade age, presence of relict species, intra-
and inter-specific genetic diversity, Atlantic affinities and extant
distributions. Evidence for Neogene origins in geologically active subregions
of the Indian Ocean (Red Sea, Arabian Sea, Mascarene Islands) is derived from
intra- and inter-specific genetic diversity and endemism. The passive tectonic
remnant margins of Gondwana (East Africa and Madagascar coasts), combined with
prevailing ocean currents, are hypothesized to have provided a stable
evolutionary refuge and region of species accumulation, perhaps since the
Palaeogene.



 



Main
conclusions



The
evidence supports multiple ‘centres of origin’ for Indian Ocean corals, first
in the Palaeogene Tethys Sea, then in the Neogene Red Sea, Arabian Sea and
Mascarene Islands. The tectonically inactive East African and Madagascar coasts
provide an evolutionary museum for old and new lineages, forming a second and
phylogenetically distinct peak of global tropical scleractinian coral
biodiversity in the Northern Mozambique Channel.





David Obura


CORDIO East Africa
#9 Kibaki Flats, Kenyatta Beach, Bamburi Beach
P.O.BOX 10135 Mombasa 80101, Kenya
www.cordioea.net ; Email: dobura at cordioea.net; davidobura at gmail.com
Mobile: +254-715 067417; skype dobura; Twitter @dobura