Oceans, for example, contain nearly 300 000 identified species (though actual numbers may lie in the millions) and have absorbed one-third of the carbon dioxide resulting from human activities (Bijma et al., Today, 60% of the world’s major marine ecosystems have been degraded or are being used unsustainably (UNEP, 2011). Many fisheries are over-exploited, with some stocks on the verge of collapse, and coral reefs are bleaching due to exposure to high temperatures and other pressures.