Pacherres cautions that such adaptations can protect an organism only to some extent. “They have the tools to withstand certain things, but past that limit there’s not enough they can do. For example, if it’s hot, we [humans] can sweat to alleviate the heat. But if it gets too hot, we die,” he says. “At one point sweating is not enough.”
But whatever heat-beating tools corals do have can help scientists develop protection strategies. Baby corals that can withstand stress are especially important for conservation efforts because they can travel between reefs and potentially share heat-tolerant genes in new locales. “The larvae from those reefs are already preadapted to some degree to rising temperatures, so we need to protect them because they’re in some ways the source of the future,” says Madhavi Colton, a conservation scientist who researched science-based tactics to save corals at the nonprofit Coral Reef Alliance.
Natural coral adaptations can also aid direct interventions like stress-hardening corals in nurseries before planting them back into ocean reefs. “You need to grow corals that are more likely to survive than the corals that died before,” Palacio says. If researchers can persuade corals to adopt heat-resistant algae or if they activate genes that can deal with heat stress, it raises the corals’ chance of surviving future ocean heat waves.
“When you dive and see a beautiful healthy reef with these colorful corals … I still feel this euphoria of being in this whole alien underwater world,” Huffmyer says. “It’s hard to go back after a bleaching event and see it dead. But that does give you the motivation to want to use whatever your skill set is, whatever your passion is, to try to help.” {read}