Scientists aboard the E/V Nautilus spotted something extraordinary 5,800 feet below the surface near Darwin Island in the Galápagos: a tiny blue octopus, no bigger than a golf ball, unlike anything marine biologists had ever seen before. The creature emerged from the darkness as a remotely operated vehicle (ROV) scanned the seafloor near an underwater mountain, and what began as a single sighting would lead to one of the most consequential recent discoveries in deep-sea biology—not because of what the octopus does, but because of what it reveals about how little we know about the ocean beneath us.
The Galápagos Islands have long captivated scientists as a natural laboratory of biodiversity, home to more than a thousand plant and animal species found nowhere else on Earth. Yet the deep waters surrounding these islands remain almost entirely unexplored. During a 2015 expedition conducted in collaboration with the Charles Darwin Foundation and the Galápagos National Park Directorate, researchers captured not just one specimen but video footage of two others like it, all with the same striking blue coloration. When the collected specimens arrived at the Charles Darwin Research Station, the tiny octopus immediately caught the attention of researchers sorting through dozens of deep-sea specimens. They knew they had something exceptional, but had no idea which species it belonged to.
The mystery led them to Janet Voight, a curator emerita of invertebrates at the Field Museum in Chicago and an octopus expert with four decades of research into octopus evolution. "Right away, I knew it was something really special," Voight recalls. "I'd never seen anything like it." Describing a new octopus species typically requires examining internal details—the mouth, beak, and teeth—which usually means dissecting the specimen. With only one individual in hand, Voight faced an impossible choice: destroy her only sample to study it, or find another way.
The solution came through an innovative technique that preserved the specimen while revealing everything inside it. Working with Stephanie Smith, manager of the Field Museum's X-ray computed tomography laboratory, Voight used micro CT imaging—essentially thousands of digitally compiled X-ray slices that create a detailed 3D model of an object without ever opening it. The scans revealed the octopus's internal organs with such clarity that Voight and her international team, including Alexander Ziegler from the University of Bonn, could identify all the anatomical features necessary to declare it a new species to science.
The octopus was formally named Microeledone galapagensis, making it officially the first new octopus species Voight has led her team in describing during her distinguished career. But the real significance extends far beyond a single specimen. These findings underscore a profound truth about our planet: the deep ocean remains a frontier as mysterious and largely unseen as outer space. "These are little octopuses that live in the deep sea, and hardly anybody on Earth has ever gotten to see them," Voight reflects. Each discovery in these unexplored depths—whether a thumb-sized octopus or the innovative imaging technique that revealed it—reminds us that wonder and discovery await us not on distant worlds, but in the waters surrounding our own islands.