Ruth GatesHawai‘i Institute of Marine Biology

Ruth Gates, who died Thursday at age 56, was known as much for her laugh as for her science. She laughed easily, loudly, and infectiously. When she first snorkeled around Heron Island, in Australia’s Great Barrier Reef, she reportedly laughed so loudly that boat drivers could hear her from the surface. “Laughing even underwater—that’s Ruth,” says Tracy Ainsworth, a close friend and coral scientist at The University of New South Wales at Sydney. “She was so thrilled by the reef that she couldn’t contain her joy.”

Coral scientists have little to laugh about these days. Between rising temperatures, acidifying water, pollution, diseases, storms, and other threats, reefs around the world are dying, transforming from bountiful worlds of color and life into deathly realms of spectral white. Half the world’s reefs have died in the past few decades. Even the mighty Great Barrier Reef is a shadow of its former glory. Every year, the drumbeat of doom-filled news seems to pound more loudly. For the many scientists who have devoted their lives to studying these ecosystems and are now forced to watch their slow demise, it can be hard to stay afloat.

But Ruth Gates was never given to doom. As one of the world’s foremost coral scientists, she was under no illusions about the perils that corals face—but she was relentlessly optimistic nonetheless. She firmly believed that reefs could be saved and was looking for ways to do so, perhaps by breeding hardier varieties of corals that could better weather the climatic upheavals of the future.

In part, Gates’s optimism was an explicit strategy meant to spur others into action. But it was also a profound part of her identity. Even colleagues who describe themselves as glass-half-full people told me that they would ask “What would Ruth do?” when they felt despair. Others spoke about her irrepressible enthusiasm and riotous sense of humor.

Gates passed away five months after she was first diagnosed with brain cancer. She is survived by her wife, Robin Burton-Gates; her brother, Tim Gates; her extended family; and a vast community of colleagues and friends. “We constantly laughed, even through her treatments,” says Burton-Gates.

To lose anyone is tragic, but to lose someone like Gates—an optimist’s optimist, a cornerstone of hope—is especially so. Her friends collectively describe her as someone who truly contained multitudes. Empath and fighter, iconoclast and team player, introvert and spokesperson—she was all these things, as well as an outspoken advocate for corals and the people who study them. “She was radiance that we were privileged to gather around, our hands toward the fire,” said Ouida Meier, one of her lab managers, in an email to her team.

Gates, who was born in England, decided she wanted to be a marine biologist in elementary school, after watching Jacques Cousteau documentaries. “She was told she wasn’t smart enough, and that she should go into athletics instead,” Burton-Gates recalls. In typical fashion, she ignored her detractors and did both. She eventually became the director of the Hawai‘i Institute of Marine Biology and the founder of a nearby karate school, the Coconut Island Dojo. A third-degree black belt, she would do knuckle and fingertip push-ups to the sound of breaking waves. And “when she hit the practice bag, it sounded like a gun going off,” says Burton-Gates.

This path to scientist and sensei was a long one. She moved to Jamaica in 1985 as a naive graduate student who just happened to find herself studying Caribbean corals at a time when they were starting to die. The corals would expunge the colored microscopic algae that live in their tissues and provide them with nutrients, becoming wan and weak in the process. Gates showed that these bleaching events were more common in warmer waters—a crucial connection that decades of later work would confirm. “It was a terribly important discovery,” says Peter Edmunds of California State University at Northridge, a coral scientist and close friend of 34 years.

After getting a doctorate in 1990, Gates moved to UCLA. That period, Edmunds says, was difficult. She spent 13 years stumbling through four separate stints as a postdoctoral researcher and published papers at a slow pace. Still, she learned to use the new tools of molecular biology to make important discoveries about the relationship between corals and their algae, the molecules they use to communicate, and how heat sunders their partnership.

That work really started taking off in 2003, when Gates joined the University of Hawai‘i and started her own lab. She and her team showed that coral algae come in several genetically distinct varieties. “They used to just be green balls, but Ruth showed us that, oh my God, these things are so much more diverse than we thought,” Edmunds says. “That really made her name.” Crucially, these algal varieties affect how their hosts cope with environmental stress. Because bleaching events were becoming more common, Gates started wondering whether corals could escape these catastrophes by shuffling out their old partners for sturdier ones. And perhaps, she suggested, scientists should give them a hand.

That is the idea she is best known for. She and her colleague Madeleine van Oppen recently won a $4 million grant for a four-year project to breed “super corals” by fast-forwarding their evolution. Their strategy, aptly for marine science, is three-pronged. Some team members are trying to breed the corals themselves, selecting for hardier ones in the way that farmers might breed more drought-tolerant crops. Others are working out whether resilient corals can pass their endurance to their offspring, and how that might work. Still others are focusing on the algae, to see how corals can be persuaded to take up unfamiliar heat-tolerant strains. The project is now into its fourth of five years of funding. “It’s so sad,” says van Oppen. “It’s just starting to take off and now she’s gone.”

It is easy to see a successful scientist and think that she emerged fully formed, like Athena from Zeus’s head. But Gates’s oldest friends remember when she was a hard-drinking, chain-smoking, 20-something wild child—an identity she walked away from when her father died from alcohol-related illness. When I interviewed Gates last year, she recalled that her therapist once told her that you can’t control what people do to you or what happens around you. You can only control your response. “That was a profound statement,” she told me, and it changed how she saw not only her own life, but the reefs’ as well.

She recognized that action is necessary, and that slow, hands-off research won’t cut it in a time when corals are dying so quickly. “Twenty years ago, I don’t think we really had a sense of how urgent the problem would become,” she said. “We’ll have to do something to help reefs get through 2050. We have to act now and perhaps not wait for permission.” Hence the super-coral project.

This attitude drew criticism from several other coral scientists, who argued that it wasn’t their place to intervene, or that we didn’t know enough to pull it off, or that such work would distract from the more important goal of stopping climate change. Gates held firm. “She was always a disruptor,” says Virginia Weis of Oregon State University, who knew her for 29 years. She suspects that Gates faced backlash not just because of her action-oriented views, but also because she was a woman scientist who didn’t conform to traditional views of femininity. “The Aloha-shirt-wearing guys were threatened by her, and it didn’t faze her. She wasn’t quiet or silent.”

She was also a “restless academic,” Weis says. She did the conventional work of publishing papers, but only later in her career did she find a more fulfilling pursuit: public speaking. She excelled at it, holding forth about her work at the United Nations, as part of the Aspen Ideas Festival, in the Emmy-winning documentary Chasing Coral, and in many public lectures. She jokingly attributed her success to her English accent.

Shayle Matsuda, one of her students, sees it differently. He first saw her speak about corals at a high-school chapel in Honolulu with both urgency and positivity. “You could have heard a pin drop in there,” he says. “It felt like she was taking everyone by the hand and talking only to them. It was one of the most powerful experiences I’ve had, and it convinced me that we really can change the narrative around climate change. It’s not just going to be research that saves reefs. It’s also about reaching people, and moving them out of the paralysis that comes from our situation.”

He, and others I spoke with, were struck by how often Gates admitted that she could be wrong, that her approach might fail, and that there was so much she did not know. In this, too, she was iconoclastic. “She wasn’t ego-driven; she was mission-driven,” says Hollie Putnam of the University of Rhode Island, who was one of Gates’s students. “That’s so rare for people at the top of their field. She wanted what was good for corals, people, and science. She didn’t want to build a kingdom.”

The kingdom sprang up around her nonetheless. Her work turned her into a rock star of coral science—a role that she publicly embraced, but that wore on her privately. Weis describes her as “a classic introvert on a stage”—someone who seemed to embody extroversion, but who secretly longed for quieter company. Such moments became rarer as her career took off. “She’d shake her head and wonder: How did this happen?” says Edmunds, who recalls freer days of sitting on a dock in a bay in Jamaica, watching passing comets. “In many ways, she still felt like just a grad student. Most people didn’t see that, but it colored so much of what Ruth did.”

For example, she always made time for people, even when it became hard to pin her down. “She’s here, there, everywhere, until she’s with you—and then she’s really with you. Her support was complete and concrete,” says Kim Cobb of the Georgia Institute of Technology. “There was an endless amount of her, and everyone felt like they had their own piece,” adds Weis.

Gates especially advocated for people who, like her, faced extra challenges in science because of their gender or sexuality. When she took over the presidency of the International Society for Reef Studies, she intentionally diversified its largely white, male staff. “Ruth was the first person I had a candid conversation with about what it meant to be a woman in science,” says Beth Lenz, who was one of her students. And Matsuda, who is transgender, adds: “She helped me grow into my scientific identity wholly, and pushed me to be my authentic self unapologetically.”

Gates was like a living embodiment of the worlds she studied—a reef in human form. Reefs enrich the oceans by creating spaces in which thousands of diverse species can thrive. Gates nurtured a vast community of researchers by opening doors for them and supporting their lives.

Reefs are built on cooperation between disparate creatures: corals, algae, and more. Gates prized cooperation, eschewing the competitive rat race of academia and recruiting people who would evince the same generosity of spirit. “Ruth told me that scientists can make the mistake of thinking that critically evaluating information is the same as being critical,” says Ainsworth. “She was the antithesis of this. Her work was always about building others up.”

Reefs also come in various forms. Some scientists are looking for so-called bright spots that are disproportionately vibrant and resilient despite the challenges they face. “Ruth herself was our bright spot,” says Rebecca Vega Thurber of Oregon State University. “Losing her feels like a horrible metaphor.”

“It’s now on us, the dozens of scientists she trained and took under her wing,” Vega Thurber adds. “We’ve put so much faith in her as our leader, our torchbearer. Now it’s time we became bright spots ourselves.”

In the last interview I did with Gates, she said she was heartened by the drive she saw in the young researchers entering the field. She was, as ever, optimistic. I asked her how she stayed that way, despite the decades of ecological decline that she had witnessed. “I don’t think a lot about what’s happened in the past and whether it’s better than what it is now,” she told me. “I’m pretty much always in the present.

“Maybe that’s a lucky personality trait for these crazy declines,” she added. “I try not to spend a lot of time mourning loss.”

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