Meet Underwater Biologist Sönke Johnsen

Nov 21, 2016

Sönke Johnsen was always driven by art. As a youth he captured documentary photos on the streets of Pittsburgh and developed them in a homemade dark room. Later he practiced and taught modern dance. But Johnsen's pursuit of artistic awe led him on a surprising path toward biology. Today, as a professor of biology at Duke University, he plunges thousands of feet under the sea, discovering mysterious marine animals that hide in plain sight. He has won multiple awards for his scientific writing, teaching, and mentorship.

In the open ocean, there is nowhere for small animals to go, Johnsen explained to The State of Things host Frank Stasio. There is no rock or leaf to mimic, and if small crustaceans or fish are spotted by predators, they are ultimately doomed. Instead, these animals find ways of using light to their advantage.

“In the open ocean, you see all these other tricks that are almost magical. They use mirrors, they use transparency, they use lights in ways that can make them look like water,” Johnsen said.

A problem that still persists for creatures that have mastered the skill of transparency is that some light usually bounces back. One crustacean studied by Johnsen’s lab at Duke University has adopted a personal colony of bacteria that grows on its entire body except for its eyes. Johnsen has found that the bacteria have surprising anti-reflective properties.

“They are the exact right refractive index and thickness to reduce pretty much all the reflective light from the animals, so they are sort of farming their own invisibility cloak,” said Johnsen.

Ultimately, he hopes that by uncovering the life stories of curious marine life he will spark interest in the sea and solidify the cry for the preservation of their habitat. His photos of these creatures have been featured in publications including The New York Times, and National Geographic.

He told The State of Things host Frank Stasio about one such oddity: the cleaner shrimp which has a unique symbiotic relationship with nearby fish.

The shrimp will wave their antennae or clap and signal for fish to stop nearby, Johnsen explained. The fish then changes color and the shrimp approaches. They clean their gills and mouths. When the fish is content with the job, it swims off.

“It looks for all the world like a pit stop. It’s adorable,” Johnsen said.

His science can often be applied to practical issues, like human cataracts. Johnsen admitted that application to human causes is not the determining factor guiding his work.

“We do have a bit of a closet agenda. We want to incorporate art into the science,” Johnsen said. “Sometimes I feel a bit out of place as a scientist because I’m really drawn by the aesthetics of a question,” said Johnsen. “We try to give people more than one way of understanding something.”