Coral reefs are among the most diverse and productive ecosystems on Earth, but they are also threatened by global warming, ocean acidification, pollution and overfishing. A new study, based on the largest genetic inventory of corals ever conducted, reveals how some corals can cope with these stressors and what factors influence their resilience.
The study, published in the journal Science, is the result of the Tara Pacific expedition, a two-year voyage across the Pacific Ocean that sampled more than 40,000 corals from 22 countries. The researchers analyzed the DNA of the corals and their symbiotic algae, which provide them with energy through photosynthesis.
They found that corals have different strategies to adapt to environmental changes, depending on their location, depth and species. Some corals can switch or shuffle their algal partners to better match the local conditions, while others can modify their own gene expression or rely on their microbiome, the community of bacteria and other microorganisms that live on and in them.
The study also identified hotspots of coral diversity and resilience, such as the Coral Triangle in Southeast Asia and some remote islands in the central Pacific. These areas could serve as refuges and sources of larvae for coral restoration in other regions.
The researchers hope that their findings will help inform conservation efforts and management policies to protect coral reefs and the services they provide to millions of people around the world.
