BOB HIRSHON (host):
Super-sharp sea urchin teeth…I’m Bob Hirshon and this is Science Update.
Sea urchins protect themselves from the pounding waves of the intertidal zone and from hungry sea otters by literally chewing through stone. They use their super sharp teeth to dig safe hideaways for themselves. But despite all the wear and tear on their teeth, they never get dull, according to University of Wisconsin, Madison biophysicist Pupa Gilbert. She says the teeth are made of nanoscale layers of super-hard calcite crystals separated by a softer organic material. When the softer layer is worn away by wear, a new layer of hard crystal emerges.
PUPA GILBERT (University of Wisconsin, Madison):
They are continuously sharpening themselves as they are being used. And the part that does the grinding actually becomes sharp as it grinds.
She says the structure of the sea urchin’s teeth could inspire the invention of nanomaterials that never go dull. I’m Bob Hirshon, for AAAS, the science society.