Extreme strength observed in limpet teeth
نویسندگان
چکیده
The teeth of limpets exploit distinctive composite nanostructures consisting of high volume fractions of reinforcing goethite nanofibres within a softer protein phase to provide mechanical integrity when rasping over rock surfaces during feeding. The tensile strength of discrete volumes of limpet tooth material measured using in situ atomic force microscopy was found to range from 3.0 to 6.5 GPa and was independent of sample size. These observations highlight an absolute material tensile strength that is the highest recorded for a biological material, outperforming the high strength of spider silk currently considered to be the strongest natural material, and approaching values comparable to those of the strongest man-made fibres. This considerable tensile strength of limpet teeth is attributed to a high mineral volume fraction of reinforcing goethite nanofibres with diameters below a defect-controlled critical size, suggesting that natural design in limpet teeth is optimized towards theoretical strength limits.
منابع مشابه
Optimized nanoscale composite behaviour in limpet teeth.
Limpet teeth are striking examples of a biological fibrous nanocomposite consisting of goethite mineral within a polymeric chitin matrix. The mechanical function of limpet teeth is critically dependent on the efficient composite behaviour of goethite, formed as distinct discontinuous nanofibres, reinforcing the matrix. The mechanical properties of discrete volumes from a limpet tooth measured u...
متن کاملThe giant keyhole limpet radular teeth: A naturally-grown harvest machine.
The limpet radula is a feeding organ, which contains more than 100 rows of teeth. During their growth the teeth mature and advance in position along the radula. The simpler doccoglossan radulae operate by grinding rocky substrates, extracting the algae by rasping and scraping with the teeth functioning as shovels. Less is known about the rhipidoglossan radulae, used as rakes or brooms that brus...
متن کاملSoft dentin results in unique flexible teeth in scraping catfishes.
Teeth are generally used for actions in which they experience mainly compressive forces acting toward the base. The ordered tooth enamel(oid) and dentin structures contribute to the high compressive strength but also to the minor shear and tensile strengths. Some vertebrates, however, use their teeth for scraping, with teeth experiencing forces directed mostly normal to their long axis. Some sc...
متن کاملدیسپلازی عاجی تیپ I گزارش دو مورد از یک خانواده
Dentinal dysplasia type 1 is a rare herediatary disease which is attributed to an automosal dominant trait. It's incidence is about 1: 100.000. Both dentition are affected with, although the involved teeth have a normal size, shape and consistency, and they are occasionally amber. The most common clinical feature, due to their extreme mobility, is malalignement and malpositioning of teeth. Such...
متن کاملLimits to optimization: fluid dynamics, adhesive strength and the evolution of shape in limpet shells.
Limpets are commonly found on wave-swept rocky shores, where they may be subjected to water velocities in excess of 20 m s(-1). These extreme flows can impose large forces (lift and drag), challenging the animal's ability to adhere to the substratum. It is commonly thought that the conical shape of limpet shells has evolved in part to reduce these hydrodynamic forces while providing a large ape...
متن کامل