What was done
The authors examined the symbiont diversity in a scleractinian coral, Oulastrea crispata, throughout its entire latitudinal distribution range in the West Pacific, i.e., from tropical peninsular Thailand (<10°N) to high-latitudinal outlying coral communities in Japan (>35°N), using "polymerase chain reactions (PCR), restriction fragment length polymorphism (RFLP), and phylogenetic analyses of DNA sequences of the nuclear large subunit (lsu) of rDNA," while "single-stranded conformational polymorphism (SSCP) of PCR products was employed to assess its higher sensitivity for low-abundance PCR products in mixed samples."

What was learned
The results of this enterprise convincingly demonstrated, "for the first time," in the words of the six scientists who conducted the study, "that phylotype D is the dominant Symbiodinium in scleractinian corals throughout tropical reefs and marginal outlying non-reefal coral communities." In addition, they learned that this particular symbiont clade "favors 'marginal habitats' where other symbionts are poorly suited to the stresses, such as irradiance, temperature fluctuations, sedimentation, etc."

What it means
Being a major component of the symbiont repertoire of most scleractinian corals in most places, the apparent near-universal presence of Symbiodinium phylotype D provides, according to Lien et al., "a flexible means for corals to routinely cope [our italics] with environmental heterogeneities and survive the consequences (e.g., recover from coral bleaching)," which suggests that the climate-alarmist claim of the impending demise of the majority of earth's corals in the face of continued global warming may be little more than a fairy tale from the dark side.