Why does a narwhal have a 9-foot tooth—and what does it actually do?
While students often use breaks to study or relax, Case Western Reserve University School of Dental Medicine alumnus Martin Nweeia, DMD (DEN ’84), chose a different path. He traveled to remote Amazonian villages and a distant atoll near Yap Island in Micronesia to study childhood dental disease, hoping to return in time for his senior-year clinical rotations.
This same curiosity has shaped his research and dental career for over forty years. A curiosity that led to uncovering the sensory secrets of one of nature's most mysterious creatures—the narwhal. Today he is known as the world’s leading expert on the narwhal tusk.
Join Martin Nweeia, DMD (DEN ’84), during Homecoming and Reunion Weekend at the Cleveland Museum of Natural History for this curious alumnus-featured talk, "Narwhal: A Tusk with a Twist."
Friday, Oct. 9
5:30 p.m. Presentation
6:15 p.m. After the lecture, stay for a virtual reality visit with the Narwhal whale and enjoy other museum exhibits, along with cocktails and appetizers.
From Childhood Curiosity to Arctic Expeditions
Nweeia became interested in dentistry and medicine at age 14. After reading a Time-Life book that highlighted the University's innovative medical program, he grew curious about science and dentistry. Later, as a student in the School of Dental Medicine, his interests expanded beyond human teeth to include how teeth evolved and their shapes in different species.
While dental school taught him standard evolutionary principles, one creature’s anatomy refused to fit the rules: the narwhal. Its nine-foot spiraled tusk—technically an overgrown upper canine tooth—seemed to challenge virtually every established rule of evolutionary biology. Driven by a desire to explore the questions that standard dental training could not answer, Nweeia set out to decode why nature would evolve such an unusual feature.
This quest led to decades of research in the High Arctic. Over 18 summer expeditions, he camped along ice-free inlets in Nunavut, Canada and Greenland. Working with researchers from Fisheries and Oceans Canada, Nweeia built strong relationships with local Inuit hunters and elders. Their traditional knowledge helped his team safely catch, study, and release 1,600-pound whales in icy waters in under 30 minutes.
Unlocking the answer
In 2014, after years of fieldwork and lab analysis, Nweeia and his team made a remarkable discovery: the narwhal tusk is actually a complex, hydrodynamic sensory organ.
Human teeth are covered by hard enamel, but the outer layer of a narwhal's tusk is porous and contains nine million tiny nerve connections that are exposed to cold seawater. This special system lets the whale sense small changes in ocean salinity, temperature and pressure, which helps it navigate sea ice, find food and track mates.
"Though I enjoy the scientific and artistic challenges of general dentistry, the very nature of how teeth evolved and are functionally relevant to myriad mammals is still very much unexplored," Nweeia explains. "I’m not sure I chose academia, as the world of teeth and my curiosity drew me into this world of wonder."
Today, Nweeia has many roles. He is an assistant professor in the School of Dental Medicine’s Department of Comprehensive Care, a lecturer at Harvard School of Dental Medicine, a research associate at the Smithsonian Institution and a National Geographic Explorer. His discoveries have appeared on the covers of Nature, Science and The New York Times and have inspired documentaries by the BBC and National Geographic.
The Endless Pursuit of Discovery
Looking back on his career, Nweeia says that breakthroughs come from staying curious:
"Finding new pathways to solve clinical problems and the discovery of an unexpected observation of dental form and function... can lead to new questions which propel curiosity and ongoing pursuit," said Nweeia. "For me, scientific discovery is directly proportional to curiosity—it never ends if you keep your thoughts and mind open."
His open-mindedness has led to many extraordinary experiences in the field.
"My current research on the narwhal has brought me to the doorstep of some of the most brilliant minds, laboratories and institutions in the world. I have stared in the eyes of a polar bear, battled an Arctic hurricane with 120-mile-an-hour winds for three days, and survived a plane trip that almost crashed. As a student, I ventured to the Amazon while my peers vacationed on tropical islands or visited Europe. After my junior year, I secretly escaped to a remote atoll off Yap Island in Micronesia to study children's teeth. I wasn’t even sure I would make it back on time to continue my clinical studies. My father once told me, ‘The world is your oyster.’ For me, that was permission and even encouragement to explore the world and all its wonders, and I’ve never stopped."
