Self‐Sharpening Mechanism of the Sea Urchin Tooth

  title={Self‐Sharpening Mechanism of the Sea Urchin Tooth},
  author={Christopher E. Killian and Rebecca A. Metzler and Yutao Gong and Tyler H. Churchill and Ian C. Olson and Vasily Trubetskoy and Matthew B. Christensen and John H. Fournelle and Francesco De Carlo and Sidney R. Cohen and Julia Mahamid and Andreas Scholl and Anthony T. Young and Andrew Doran and Fred H. Wilt and Susan N. Coppersmith and Pupa U.P.A. Gilbert},
  journal={Advanced Functional Materials},
The sea urchin tooth is a mosaic of calcite crystals shaped precisely into plates and fibers, cemented together by a robust calcitic polycrystalline matrix. The tooth is formed continuously at one end, while it grinds and wears at the opposite end, the sharp tip. Remarkably, these teeth enable the sea urchin to scrape and bore holes into rock, yet the teeth remain sharp rather than dull with use. Here we describe the detailed structure of the tooth of the California purple sea urchin… 

Multiple deformation mechanisms in the stone of a sea urchin tooth

The sea urchin tooth is a biogenic grinding tool that exhibits unique mechanical properties during food biting and rock boring, while being almost entirely composed of intrinsically brittle CaCO3

Sophisticated Nanostructure in Stone Part of Sea Urchin Tooth: Enlightenment for Artificial Composites

Sea urchin teeth, which are used to scrape rocks for food, assume significant mechanical functions. Unraveling their design strategies could provide inspiration for the pursuit of high-performance

Macro- and microstructural diversity of sea urchin teeth revealed by large-scale mircro-computed tomography survey

A broad survey identifies key taxa for further in-depth study and integrates previously assembled data on fossil species into a more comprehensive systematic analysis of sea urchin teeth, and introduces shape analysis algorithms that will permit the numerical and therefore more objective description of tooth macrostructure.

Parrotfish Teeth: Stiff Biominerals Whose Microstructure Makes Them Tough and Abrasion-Resistant To Bite Stony Corals.

Parrotfish enameloid consists of 100 nm-wide, microns long crystals co-oriented and assembled into bundles interwoven as the warp and the weave in fabric and therefore termed fibers here, and this size decrease is spatially correlated with an increase in hardness.

Lawrence Berkeley National Laboratory Recent Work Title Parrotfish Teeth : Stiff Biominerals Whose Microstructure Makes Them Tough and Abrasion-Resistant to Bite Stony Corals Permalink

Parrotfish (Scaridae) feed by biting stony corals. To investigate how their teeth endure the associated contact stresses, we examine the chemical composition, nanoand microscale structure, and the

X-ray Linear Dichroism in Apatite.

PIC maps of lamellar bone and mouse enamel reveal a complex arrangement of hydroxyapatite crystals perpendicular to the dentin-enamel junction, with rods arranged in a decussation pattern in inner enamel and nearly parallel to one another in outer enamel.

A Protocol for Bioinspired Design: A Ground Sampler Based on Sea Urchin Jaws.

Teeth from the bioinspired lantern design are bioexplored via finite element analysis to explain from a mechanical perspective why keeled tooth structures evolved in the modern sea urchins the authors observed.



Mechanism of calcite co-orientation in the sea urchin tooth.

Differences in calcite c-axis orientations in the tooth of the purple sea urchin are shown and it is demonstrated that co-orientation of the nanoparticles in the polycrystalline matrix occurs via solid-state secondary nucleation, propagating out from the previously formed fibers and plates, into the amorphous precursor nanoparticles.

The grinding tip of the sea urchin tooth exhibits exquisite control over calcite crystal orientation and Mg distribution

This work uses 3 complementary high-resolution tools to probe aspects of the structure of the grinding tip of the sea urchin tooth: X-ray photoelectron emission spectromicroscopy, x-ray microdiffraction, and NanoSIMS.

Design strategies of sea urchin teeth: structure, composition and micromechanical relations to function.

  • R. WangL. AddadiS. Weiner
  • Materials Science
    Philosophical transactions of the Royal Society of London. Series B, Biological sciences
  • 1997
The self-sharpening function of the teeth is believed to result from the combination of the geometrical shape of the main structural elements and their spatial arrangement, the interfacial strength between structural elements, and the hardness gradient extending from the working stone part to the surrounding zones.

Mineral Deposition and Crystal Growth in the Continuously Forming Teeth of Sea Urchins

The early stages of formation of the crystalline elements in the continuously forming sea urchin teeth were studied using polarized light microscopy, SEM, TEM and calcite overgrowth. Transient

Ultrastructure and growth of the sea urchin tooth

  • E. Kniprath
  • Chemistry, Medicine
    Calcified Tissue Research
  • 2005
Following the origin of a syncytium in the plumula, a new tooth element sheath originates in the form of a vesicle, which develops a unified crystallization cavity in the shape of the future tooth element during the early growth of the sheath.

Intercalation of sea urchin proteins in calcite: study of a crystalline composite material.

By means of x-ray diffraction with synchrotron radiation, it is shown that the presence of the protein in synthetic calcite only slightly decreases the coherence length but significantly increases the angular spread of perfect domains of the crystals.

Fracture Toughness and Interfacial Design of a Biological Fiber‐Matrix Ceramic Composite in Sea Urchin Teeth

The working zone of a sea urchin tooth is a ceramic-fiber-reinforced ceramic-matrix composite. It is composed of reinforcing calcitic fibers, a matrix of high-magnesium-containing calcite crystals,

Zur funktionellen anatomie der seeigelzähne (Echinodermata, Echinoidea)

SummaryThe teeth of sea urchins are built of magnesiumrich calcite. Sea urchin teeth are considerably stronger than compact calcite. They have no homogeneous crystal lattice with preferred cleavage