Narwhal Tusks – Inside Out

Music; Ambiance: Narwhal song

JM: Teeth are designed to be hard on the outside, soft and sensitive in the inside, right? Well, not always. I’m Jim Metzner and this is the Pulse of the Planet. The narwhal is an arctic whale whose 8-foot tusk-like tooth grows from its forehead and apparently breaks all the rules about how teeth are structured.

MN: “The narwhal tooth is built entirely backwards, entirely inside out. And it is the only tooth that is built this way.”

JM: Dr. Martin Nweeia is a dentist and an expert on narwhals.

MN: “The softest component of it is on the outside surface and the hardest, most dense part is the part that wraps around the nerve and blood supply of the tooth. This is also completely odd. You know, scientists are completely reluctant to use words like “always, never;” we always love to say things like “sometimes” or “possibly.” This is one case where you can really use a superlative and be on very firm ground. The amount of flexibility that was exhibited, by this tooth being inside out, was correlated with an overall flexibility. So that in an eight-foot tusk, this has the ability to flex one foot in every direction without breaking. You just don’t see this kind of architecture anywhere else. And you have to think, well, how did this thing get created, you know, what was the evolutionary model that drove this thing to be created? And these are the questions that cause you to try to find out what information is locked within this spiral tooth. And if you have that insight, you understand the potential of what other teeth can do. Because in this case, it likely is a possibility that is in with all teeth, but is only expressed, in this one example perhaps, in nature. But it can cause us to reflect upon possible functions of even human teeth.”

JM: Pulse of the Planet is made possible in part by the National Science Foundation and Virginia Tech, inventing the future through a hands-on approach to education and research.

Narwhal Tusks - Inside Out

Teeth are ideally strong, hard, and pearly white, right? Not for the narwhal and its inside out tusk.

Air Date:06/22/2006

Scientist:

Transcript:

Narwhal Tusks - Inside Out

Music; Ambiance: Narwhal song

JM: Teeth are designed to be hard on the outside, soft and sensitive in the inside, right? Well, not always. I'm Jim Metzner and this is the Pulse of the Planet. The narwhal is an arctic whale whose 8-foot tusk-like tooth grows from its forehead and apparently breaks all the rules about how teeth are structured.

MN: "The narwhal tooth is built entirely backwards, entirely inside out. And it is the only tooth that is built this way."

JM: Dr. Martin Nweeia is a dentist and an expert on narwhals.

MN: "The softest component of it is on the outside surface and the hardest, most dense part is the part that wraps around the nerve and blood supply of the tooth. This is also completely odd. You know, scientists are completely reluctant to use words like "always, never;" we always love to say things like "sometimes" or "possibly." This is one case where you can really use a superlative and be on very firm ground. The amount of flexibility that was exhibited, by this tooth being inside out, was correlated with an overall flexibility. So that in an eight-foot tusk, this has the ability to flex one foot in every direction without breaking. You just don't see this kind of architecture anywhere else. And you have to think, well, how did this thing get created, you know, what was the evolutionary model that drove this thing to be created? And these are the questions that cause you to try to find out what information is locked within this spiral tooth. And if you have that insight, you understand the potential of what other teeth can do. Because in this case, it likely is a possibility that is in with all teeth, but is only expressed, in this one example perhaps, in nature. But it can cause us to reflect upon possible functions of even human teeth."

JM: Pulse of the Planet is made possible in part by the National Science Foundation and Virginia Tech, inventing the future through a hands-on approach to education and research.