Self-Sharpening Mechanism of the Sea Urchin Tooth (pages 682–690)
Christopher E. Killian, Rebecca A. Metzler, Yutao Gong, Tyler H. Churchill, Ian C. Olson, Vasily Trubetskoy, Matthew B. Christensen, John H. Fournelle, Francesco De Carlo, Sidney Cohen, Julia Mahamid, Andreas Scholl, Anthony Young, Andrew Doran, Fred H. Wilt, Susan N. Coppersmith and Pupa U. P. A. Gilbert
Article first published online: 22 DEC 2010 | DOI: 10.1002/adfm.201001546
Five white, calcitic teeth are at the center of a sea urchin, shown upside down. Using these teeth sea urchins can bore into rocks, whereby the teeth are seen to self-sharpen with use rather than dull. Here, the self-sharpening mechanism is described, in which the continuously growing teeth wear at pre-determined locations near the tip, and thus renew and maintain a sharp tip profile.