Using DNA to figure out soft coral taxonomy: phylogenetics of Red Sea octocorals

Abstract

The knowledge of evolutionary relationships between taxonomic groups is fundamental to a range of further studies. For example, it allows for studies on ecological interactions (competition, symbiosis, etc.) between different species of octocorals, or between octocorals and other marine organisms, such as scleractinian (hard) corals. This is of specific interest now, when hard corals are affected by global climate change (Hughes et al. 2003; Hoegh-Guldberg et al. 2007). An ecological shift from scleractinian dominated coral reefs to alcyonacean soft corals may result from a combination of environmental changes impacting hard corals, and opportunistic features of soft corals such as rapid growth rates, high fecundity, and extensive vegetative reproduction (Fabricius 1995, Tilot et al. 2008, Wood & Dipper 2008). Furthermore, a better understanding of evolutionary relationships allows analyses of ecological differences between taxonomic groups, such as reproduction methods or habitat preference. Moreover, genetic barcoding will allow geographic comparisons which may reveal range-restricted endemics and novel evolutionary lineages. In conclusion, the data produced by this study will provide robust scientific foundations for a variety of further biological studies, as well as conservation management decisions, and we will highlight taxonomic groups that require further attention.