New super global warming resistant corals could be tested on the Great Barrier Reef within a year as part of a global research effort to accelerate evolution and save the “rainforests of the seas” from extinction.
Researchers are getting promising early results from cross-breeding different species of reef-building corals, rapidly developing new strains of the symbiotic algae that corals rely on and testing inoculations of protective bacteria. They are also mapping out the genomes of the algae to assess the potential for genetic engineering.
Innovation is also moving fast in the techniques need to create new corals and successfully deploy them on reefs. One breakthrough is the reproduction of the entire complex life cycle of spawning corals in a London aquarium, which is now being scaled up in Florida and could see corals planted off that coast by 2019.
Coral reefs are critical ecosystems in the oceans, hosting more than a million species and sustaining natural services worth $10tn a year, including providing vital food for 500 million people. But climate change is heating the oceans and causing corals to bleach: reefs could die out as early as 2050, with perhaps half already gone.
* Corals adapted to cooler water can be crossed with other species from warmer regions so that the hybrids withstand heat better.
* Another approach is to toughen up the symbiotic algae that live in the coral animals’ tissues and provide them with food. Leela Chakravarti, one of van Oppen’s team, pushed the algae through 80 generations in the lab, each time selecting for the most heat tolerant, and produced symbionts that could survive 31C water temperature. The experiment proved the concept and now the team looking for ways for the corals themselves benefit from the rapidly evolved algae.
* inoculating corals with a cocktail of 10 hydrocarbon-eating bacteria helps them survive oil spills.
Genetic engineering is also being explored, as it may be a fast way to get protective genes into corals and symbiotic algae.
* Other new technology presented at the Oxford conference included three-pronged concrete bases to grow corals on in tanks, which can then be wedged into reefs without time-consuming ties or glue.
* Another is a “badminton technique” for delivering small tank-grown corals to trawler-damaged habitats deep in the Mediterranean. “The fan shape of the coral acts like a badminton shuttlecock and slows the descent, allowing a good landing,” said Maria Montseny, at the University of Barcelona.
Biorxiv – Symbiodinium genomes reveal adaptive evolution of functions related to symbiosis Huanle Liu, Timothy G. Stephens, Raúl González-Pech, Victor H. Beltran, Bruno Lapeyre, Pim Bongaerts, Ira Cooke, David G. Bourne, Sylvain Forêt, David John Miller, Madeleine J. H. van Oppen, Christian R. Voolstra, Mark A. Ragan, Cheong Xin Chan. 2017.
Symbiosis between dinoflagellates of the genus Symbiodinium and reef-building corals forms the trophic foundation of the world’s coral reef ecosystems. Here we present the first draft genome of Symbiodinium goreaui, one of the most ubiquitous endosymbionts associated with corals, and an improved draft genome of Symbiodinium kawagutii, previously sequenced as strain CCMP2468, to further elucidate genomic signatures of this symbiosis. Comparative analysis of four available Symbiodinium genomes against other dinoflagellate genomes led to the identification of 2460 nuclear gene families that show evidence of positive selection, including genes involved in photosynthesis, transmembrane ion transport, synthesis and modification of amino acids and glycoproteins, and stress response. Further, we identified extensive sets of genes for meiosis and response to light stress. These draft genomes provide a foundational resource for advancing our understanding Symbiodinium biology and the coral-algal symbiosis.