We’re all symbiotic

To better understand how sea creatures experience their worlds, Gruber tries to imagine himself enshrouded in perpetual darkness. To emulate how a jellyfish or a shark or a sea turtle sees its glowing compatriots, he creates lenses that mimic their eyes.

“I see these intertwined, interdisciplinary aspects of life,” Gruber says. “Studying light and creatures who are conduits of light is a really alluring way for me to follow that thread of life.”

As he talks about never-before-seen biofluorescent organisms, Gruber’s hands trace shapes in the air, freezing mid-gesture as he searches for the right word. He sports metal-rimmed spectacles reminiscent of those of a 19th-century naturalist.

After squeaking through high school, Gruber chose the University of Rhode Island for its surfing team. And after a turbulent summer unloading trucks for a factory, he figured he’d better choose a different path. New Jersey’s industrial landscapes and strip malls represented a “disconnection from nature,” he says. “I was searching for nature wherever I could find it.”

As a college senior, he jumped at an opportunity to participate in an oceanography expedition to Belize. He lived in a tent on a tiny island where conch fishermen taught him to free dive and navigate by the stars in search of nocturnal fish in seagrass habitats. Later, he studied biodiversity in the jungles of Guyana and worked to restore the Everglades near Key Largo.

For a time, he pursued serial passions: a master’s in environmental management from Duke University, a master’s in journalism from Columbia University, a Ph.D. in biological oceanography from Rutgers, a postdoctoral fellowship in molecular biology at Brown University.

He joined the CUNY faculty in 2008. He wonders if he paid a price early in his academic career by being “too broad,” he says. But now his varied background helps him see unexpected connections: how phytoplankton are integral to the study of human aging, for instance, and how the scientific narrative of evolution informs almost everything.

Soon after Gruber was named a National Geographic Society Emerging Explorer in 2014, he presented his work in Washington, D.C. He talked about studying bioluminescence, which is like trying to study gasoline after combustion: Once the reaction has occurred, evidence that it existed is gone.

Despite their resilience in the wild, jellyfish are notoriously difficult to cultivate. Gruber once spent months in a hotel, dashing to the Mystic Aquarium in Connecticut at all hours, coaxing baby jellyfish to thrive in a lab tank, tweaking their diet in the hope that they would produce more light.

After the talk, the Harvard roboticist Robert J. Wood, one of the other NatGeo Explorers, approached him. Have you heard of soft robotics? Wood asked. Gruber hadn’t, but he immediately recognized its potential for collecting deep-sea marine samples noninvasively.

He and Wood are collaborating this year in the Harvard Microrobotics Laboratory to create squishy-fingered robot hands that can grasp a jellyfish without harming it. In the spring, they hope to test their devices on living jellyfish in Boston Harbor, following the lead of the Harvard naturalist Louis Agassiz, who researched jellyfish off Nahant in the 1850s.

Much more has been learned about jellyfish physiology since Agassiz’s time. The creatures have sleep cycles, just as we do, Gruber points out, and senses. They have eyes and a knack for sophisticated navigation. With uncanny efficiency and balletic grace, they propel away from predators.

“They’re incredibly delicate,” he says. “They seem so simple, yet they’re complex. They’re little packets of water that can do miraculous things,” such as descend to depths that would crush a titanium submarine. “They have lots of charisma, if we dig in.”

Gruber holds a glass jar containing a cannonball jellyfish, a specimen Agassiz brought back from Georgia, which is stored in the bowels of the Harvard Museum of Comparative Zoology. Inside the jar a colorless gelatinous blob sloshes in clear liquid, its bell devoid of the lacy pattern it had when alive. It seems a gigantic theoretical leap to say, as Gruber does, that humans and jellyfish simply diverged from a common evolutionary path.

Jellyfish or river organism or fellow vertebrate — at the end of the day, we have many commonalities, and we all share DNA. Humans have nearly 70 percent of the same genes as sponges. But if we look only with our human eyes, Gruber insists, we miss the point.

He pauses, gazing over my head as if zeroing in on something only he can see.