Recent Reticulate Evolution in the Ecologically Dominant Lineage of Coccolithophores

Bendif, EM; Probert, I; Díaz-Rosas, F; Thomas, D; van den Engh, G; Young, JR; von Dassow, P. 2016 Recent Reticulate Evolution in the Ecologically Dominant Lineage of Coccolithophores. Frontiers in Microbiology, 7. 10.3389/fmicb.2016.00784

[img]
Preview
Text
fmicb-07-00784.pdf - Published Version
Available under License Creative Commons Attribution.

Download (5MB) | Preview
Official URL: http://dx.doi.org/10.3389/fmicb.2016.00784

Abstract/Summary

The coccolithophore family Noëlaerhabdaceae contains a number of taxa that are very abundant in modern oceans, including the cosmopolitan bloom-forming Emiliania huxleyi. Introgressive hybridization has been suggested to account for incongruences between nuclear, mitochondrial and plastidial phylogenies of morphospecies within this lineage, but the number of species cultured to date remains rather limited. Here, we present the characterization of 5 new Noëlaerhabdaceae culture strains isolated from samples collected in the south-east Pacific Ocean. These were analyzed morphologically using scanning electron microscopy and phylogenetically by sequencing 5 marker genes (nuclear 18S and 28S rDNA, plastidial tufA, and mitochondrial cox1 and cox3 genes). Morphologically, one of these strains corresponded to Gephyrocapsa ericsonii and the four others to Reticulofenestra parvula. Ribosomal gene sequences were near identical between these new strains, but divergent from G. oceanica, G. muellerae, and E. huxleyi. In contrast to the clear distinction in ribosomal phylogenies, sequences from other genomic compartments clustered with those of E. huxleyi strains with which they share an ecological range (i.e., warm temperate to tropical waters). These data provide strong support for the hypothesis of past (and potentially ongoing) introgressive hybridization within this ecologically important lineage and for the transfer of R. parvula to Gephyrocapsa. These results have important implications for understanding the role of hybridization in speciation in vast ocean meta-populations of phytoplankton.

Item Type: Publication - Article
Divisions: Marine Biological Association of the UK > Other (MBA)
Depositing User: Barbara Bultmann
Date made live: 03 Oct 2016 14:39
Last Modified: 06 Jun 2017 16:17
URI: http://plymsea.ac.uk/id/eprint/7220

Actions (login required)

View Item View Item