The revelation is logical: Mollusks utilize these teeth for rock excavation during their feeding process.
Limpets, marine snails known for their strong attachment to rocks amidst crashing waves, demonstrate remarkable tenacity. They can secure themselves with a pressure of 75 pounds per square inch, employing their muscular mollusk “foot” and a chemical secretion. However, even more impressive is their capability to grind down rock while feeding, facilitated by a tooth-studded tongue known as a radula. Recently, engineers based in the U.K. have enhanced their reputation for toughness by discovering that the teeth of these snails are composed of the strongest natural material known.
Spider silk, often likened to kevlar for its toughness and flexibility, has garnered admiration. However, upon examination, the tooth material proved to be approximately five times stronger on average than most spider silk, as per reports from BBC News. This establishes it as the strongest natural substance on the planet. Laboratory tests demonstrated its ability to withstand pressures that would typically transform carbon into diamond. According to the lead author of the study, Asa Barber from the University of Portsmouth, this strength is equivalent to a single strand of spaghetti supporting roughly 3,300 one-pound bags of sugar, as conveyed to the BBC.
For Science, David Shultz reports:
“Scientists discovered that the teeth are made of a mixture of goethite (an iron-containing crystal) nanofibers encased in a protein matrix. In spite of their amazing strength, the teeth don’t quite best the strongest humanmade materials like graphene, but the new material’s upper range puts it far ahead of Kevlar and on par with the highest quality carbon fibers”.
The researchers disclosed their discoveries in the Journal of the Royal Society Interface.
While diamond might be a common assumption for the strongest material overall, man-made nano-materials surpass it. Additionally, there are two rare natural materials capable of withstanding more stress than diamond, as per reports from New Scientist.
One of these materials, wurtzite boron nitrate, possesses a diamond-like atomic structure. Unlike diamonds composed solely of carbon, wurtzite boron nitrate also contains boron and nitrogen, as suggested by its name. The other material, lonsdaleite, consists entirely of carbon but adopts a hexagonal structure, unlike diamond’s cubic form. Lonsdaleite can be formed when graphite-containing meteorites impact the Earth and can endure 58 percent more stress than diamond.
Materials that are both hard and strong yet flexible offer appealing properties for engineers seeking to develop the next generation of materials, structures, and even machinery. Consequently, they may now turn to snails as potential sources of inspiration for such projects.
Editor’s Note April 5, 2017: A reader, Tom Tonon, has astutely pointed out that the terminology in this article could potentially cause confusion for some readers. There are numerous scientific terms used to describe an object’s resistance to bending or breaking apart, each with subtle distinctions. In this article, the terms toughness and strength refer specifically to tensile strength—the ability of an object to resist being pulled apart. This differs from compressive strength, which measures an object’s resistance to being squeezed. The discussion concerning wurtzite boron nitrate pertains not to tensile strength but rather to the hardness of the material, which denotes its resistance to scratching or cutting.
