Coral evolution tweaked for global warming
COCONUT ISLAND, Hawaii (AP) — Scientists are attempting to speed up the evolutionary clock of corals in order to develop “super corals” that can better withstand the effects of global warming in this Darwinian experiment.
The researchers have been performing studies for the past five years to establish that their beliefs are correct. They’re now preparing to release laboratory-grown corals into the ocean to test how they fare in the wild. Kira Hughes, a University of Hawaii researcher and the project’s manager, said, “Assisted evolution started out as this sort of wild idea that you could actually help something change and allow that to survive better because it is changing.”
Selective breeding, which passes on favorable qualities from parents; acclimation, which trains corals to tolerate heat by gradually exposing them to higher temperatures. As well as altering the algae that provide vital nutrients to corals. According to Hughes, all of the procedures have been successful in the lab. While other scientists are concerned that this is interfering with Nature, Hughes claims that the rapidly warming globe has no other choices. “We must intervene to make a difference if coral reefs are to thrive in the future,” she said. When the temperature of the ocean rises, coral releases its symbiotic algae, which provide nutrition and give the coral its bright colors. Bleaching causes the coral to turn white, and it can quickly grow sick and die. Scientists have been studying corals that have survived bleaching for more than a decade, even when others on the same reef have died. As a result, scientists are concentrating their efforts on the hardy survivors in the hopes of improving their heat tolerance. Selective breeding, they discovered, had the most potential for Hawaii’s reefs. “A number of stressors affect corals around the world, but rising temperatures are probably the most serious,” said Crawford Drury, chief scientist of Hawaii’s Coral Resilience Lab. “And so that’s where we’re concentrating our efforts, working with parents that are really thermally tolerant.” The resilience lab’s founder, Ruth Gates, and Madeleine van Oppen of the Australian Institute of Marine Science published a report on aided evolution during one of the world’s worst bleaching events in 2015. The researchers proposed that corals be brought inside a lab to help them grow into more heat-tolerant creatures. The concept drew the attention of Microsoft co-founder Paul Allen, who funded the initial research and whose foundation continues to support the initiative.
In a 2015 interview with The Associated Press, Gates said, “We’ve provided (coral) experiences that we think would increase their ability to live.” Gates, who died in 2018 from brain disease, also expressed her desire for people to understand how “intimately reef health is connected with human health.”
Coral reefs, sometimes known as the “rainforests of the sea,” supply food for humans and marine creatures, shoreline protection for coastal communities, tourism jobs, and even medicine to treat ailments like cancer, arthritis, and Alzheimer’s disease. Bleaching episodes, according to a recent assessment by the National Oceanic and Atmospheric Administration and other scientific organizations, are the greatest threat to the world’s coral reefs. According to scientists, the planet lost around 14% of its coral between 2009 and 2018. When assisted evolution was first postulated, it was met with skepticism. Van Oppen stated that there were concerns about genetic variety being lost, as well as detractors who claimed that the scientists were “playing gods” by meddling with the reef.
“Well, you know, (people) have already intervened with the reef for a very long time,” van Oppen remarked. “All we’re attempting to do is repair the harm,” says the narrator. Researchers are only influencing what could already be happening in the water, rather than altering genes or producing anything artificial, she explained. “We’re really trying to work on as small a scale as possible to try to sustain and enhance what’s currently there,” says the author.
There are still some unanswered questions. “We’ve uncovered a lot of reasons why corals don’t bleach,” said Steve Palumbi, a Stanford University marine biologist and professor. “Just because a coral doesn’t bleach in the field or in the lab doesn’t mean it’s heat tolerant indefinitely.” Corals have been on the planet for roughly 250 million years, but their genetic code is still a mystery. “This isn’t the first time any coral on the world has been exposed to heat,” Palumbi explained. “So the fact that not all corals are heat resistant indicates… that it has certain drawbacks. They’d all be heat resistant if there wasn’t a disadvantage.” Palumbi, on the other hand, believes that the aided evolution research has a place in coral management strategies since “reefs all over the world are in urgent, horrible, desperate difficulty.”
The idea has gotten a lot of attention and has sparked studies all over the world. Scientists in the UK, Saudi Arabia, Germany, and other countries are working on coral resilience. The United States government also supports the initiative. “It’s extremely outstanding, and it’s really consistent with a research that we did with the National Academies of Sciences,” said Jennifer Koss, director of NOAA’s Coral Reef Conservation Program. “We wanted them to compile all of the most up-to-date cutting-edge science that was truly focused on new interventions in coral reef management,” Koss explained. “And, without a doubt, this aided gene flow fits right in.”
There are still significant obstacles to overcome. One is scalability. It will be difficult to get lab-bred corals into the ocean and have them thrive, especially when reintroduction must take place on a local level to avoid transporting harmful biological material from one region to another. A research led by James Guest, a coral ecologist from the United Kingdom, aims to show that selectively bred corals may not only survive longer in warmer water, but can also be successfully reintroduced on a big scale.
“It’s fantastic if we can do all of this in the lab,” Guest said, “but we need to show that we can move a huge number of them out into the reef in a cost-effective fashion.” Scientists are experimenting with delivery techniques such as sending young corals into the ocean through ships and planting coral with miniature underwater robots. No one is claiming that aided evolution would save the world’s reefs on its own. The proposal is part of a package of solutions that includes anything from generating shade for coral to injecting cooler deep-ocean water onto overheated reefs. Planting stronger corals has the advantage of organically spreading their traits after a generation or two, without the need for much human involvement.
Over the next few years, scientists in Hawaii will reintroduce deliberately bred coral to Kaneohe Bay and monitor their behavior. Van Oppen and her colleagues have already returned several corals to the Great Barrier Reef with modified symbiotic algae. Scientists warn they are racing against the clock to save coral reefs as the world’s waters continue to warm. “All the work we are going to do here,” said Hawaii’s Drury, “is not going to make a difference if we don’t wind up addressing climate change on a global, systematic scale. “So really, what we’re trying to do is buy time.”