One thing that I really love about Biomimicry is the surprises we unfold from some of the most unlikely of sources. To me, when a new Biomimicry discovery is released, or I come across something in my readings, it’s like Christmas when something spectacular is unveiled.
This past week, the mighty Limpet has splashed its way across headlines from Canadian News to the BBC to Pakistani TV and I’m sure just about every place in between. Allegedly surpassing the strength of spider silk, limpet teeth are composed of protein frames, with closely packed nanofibers of Goethite (named after Johann Wolfgang von Geothe. In preliminary studies at the University of Portsmouth (UK), limpet teeth displayed an impressive tensile strength of up to 6.5 Gigapascals of force, compared to spider silk tensile strength, which has around 4.5 Gigapascals.
The particularly interesting thing we can abstract from this discovery immediately is the scalability. With anything that functions exceptionally well on a small-scale, that doesn’t always translate well into the same quality of functionality at a larger scale (such as aircraft aerodynamics). For limpet teeth, however, because the Goethite is so small and densely packed, overall tooth size doesn’t matter.
Articles have cited interesting applications such as stronger Formula 1 racing cars, aircraft, or bicycles. I’d like to think, however, that the mighty little limpet would like to be inspiration for additional valuable uses such as medical biomaterials or safer, stronger helmets.
I should add a caveat here about the wording of such popular articles, where much of the research is simplified for general audiences. For instance, “strength” and “toughness” can be considered different properties and these biological materials may not be able to be compared with each other directly. If limpet teeth-inspired materials are scaled up, will the weight negate positive effects? On the other hand, if spider silk-inspired materials were used instead of limpet teeth, ounce-for-ounce, it may be lighter and stronger and better for the overall form of the design. Such semantics may not be important for these popular articles, but it may make all the difference in the nuances of analytical research!