Burrs: the Inspiration for the Hook and Loop Fastener
In 1941, the Swiss engineer George de Mestral was removing burrs from his dog. These barbed seeds come from a variety of plants, and are evolutionarily specialized to attach to animals and humans as a way to spread to new areas. Commonly, however, they are seen as a source of irritation, as the barbs can be painful, and at their worst, they can cause severe damage to livestock and automobile tires. George de Mestral, however, saw something different: a potential use for the hooked barbs on the seeds he was holding.
Thus hook and loop fasteners were born, using loops and hooks attached to opposing pieces of fabric to create an easily removable fastening mechanism. This flash of insight that George de Mestral had, where he repurposed a natural system to suit human needs, is an oft-cited example of biomimicry. Through the act of reverse engineering a product of nature, he had created an infinitely applicable product, with applications ranging from consumer apparel to space travel.
Velcro-like Cells on Garden Flowers
Burrs are not the only example of the hook and loop fastener in the wild; they were simply the inspiration for the human adaptation of a widespread natural technology. Another place they can be found is on the petals of garden flowers where conical cells on the petals surface allow spaces for pollinating bees to affix their legs, similar to how hook and loop works, when wind speeds increase. Different species have different shapes of cells, but the same basic system has been observed in a wide variety of flowers, from roses to petunias to snapdragons.
This version of hook and loop biomimicry allows bees to affix themselves to the petals of flowers on windy days and thus increases the proliferation of these flower species through increased pollination. It has been observed in a laboratory setting that bees prefer flowers with this adaptation to mutant strands lacking it. While the functional reason for the evolution of this adaptation is different from that of burred seeds, the outcome is the same.
Through these natural examples, it is easy to see why the hook and loop fastener has become such a widespread part of human engineering in the last 75 years; it is a simple design with a wide variety of applications.
