What is Biomimicry?
Biomimicry is a new scientific discipline. 'Bio' comes from the Greek word bios meaning life and 'Mimicry' comes from the Greek word mimesis, which means imitate. Therefore, 'bio' + 'mimicry' = biomimicry, meaning imitating the best ideas and processes from nature and using them in innovative designs and processes to solve human problems. Biomimetics is the science of mimicking biology or nature. Nature has established itself in the field of complex engineering for over a billion years; in this enormous amount of time, complex biological processes, systems, and functions have been fine-tuned. The goal of biomimetics is to figure out how nature performs its complex functions, so that we, or scientists, can develop techniques that copy what nature does so efficiently. The core idea of biomimicry is that nature has already solved many of the problems we are still wrestling with. Not only does humanity want to copy nature's processes, its biomimetic goal is actually to surpass what nature does by doing it better.
Velcro, something familiar to all of us, is a product of biomimicry. In 1948, a Swiss inventor returned home from a nature hike with his dog both covered with burrs, the plant seed-sacs that cling to animal fur for transport to new fertile planting grounds. Microscopic inspection of one of the burrs that was stuck to his pants revealed small hooks that enabled the burr to cling to the tiny loops in the fabric of his pants. From that discovery, George de Mestral came up with the idea of the two-sided fastener commonly known today as 'Velcro' 24
Stain and water resistant fabrics are a form or biomimetics because one of the processes used for creating this property is mimicked after the lotus leaf referred to as the lotus effect. Wilhelm Barthlott, a German botanist, was the first to explain the phenomenon. The lotus effect is based on the very fine surface structure of the lotus leaf, which is coated with hydrophobic wax crystals approximately 1 nm in diameter. Rough surfaces on a nanoscale reduce the contact area between the water and the solid and therefore are more hydrophobic than smooth surfaces. The contact area of the lotus leaf is 2-3% of the droplet-covered surface.
The Shinkansen Bullet Train of the West Japan Railway Company travels 200 miles per hour and is the fastest train in the world. The problem it encountered was its noise level. The changes in air pressure, resulting from the train's emergence from a tunnel, produced loud thunderous sounds heard by residents one-quarter a mile away. Eiji Nakatsu, the train's chief engineer and an avid bird-watcher, modeled the front-end of the train after the beak of Kingfishers. Kingfishers dive from the air into bodies of water with very little splash to catch fish. This biomimetic design resulted in a quieter train, using 15% less electricity, and with a 10% increase in speed.
Although the concept of biomimicry is old, evidenced by the Wright Brother's invention of the first flying machine modeled somewhat after the flight of birds, the field has been enlarged by the capability to see matter, processes, and structures at the nanoscale. Biomimetics is applicable in many areas of society involving, but not limited to, medicine, textiles, cosmetics, energy, pharmaceuticals, military, sports equipment, and others. In the field of medicine, biomimicry occurs at the cell and molecular level for purposes such as drug delivery, cell regeneration, destruction of damaged or diseased cells, genetic engineering, and protein production. In the area of industry, new products have been developed to solve societal problems or enhanced to provide more desirable properties such as increased strength but reduced weight, stain and/or water resistance. Other areas interested in biomimicry are military, ecologists, environmentalists, and energy producers.
Biomimetics Past, Present and Future
Much of what is now learned from nature is occurring at the nano level. Processes and functions that occur at the nanoscale level facilitate nature's desirable characteristics and/or properties observed in the macro world. The emergence of nanotechnology and its accompanying tools and instruments are making these scientific discoveries possible. As you read earlier the buckyball occurs naturally in nature, although scarcely; it is a natural phenomena. But we were not able to detect it until recently. That absence of detection did not prevent man from mimicking nature, perhaps even before he know that what he constructed already existed in nature. Here are some examples to illustrate this point.
Biomimetics in the Past
Buckminsterfullerenes were not discovered until 1985 by a team of three chemists, Robert Curl Jr., Sir Harold Kroto, and Richard Smalley. I mention the buckyball, which it is called for short, because it is an object of biomimetics before anyone knew they existed. The new C 6 0 carbon molecule was named after an inventor and architect, R. Buckminster Fuller because it closely resembled-at a very different size scale-the geodesic dome that Buckminster Fuller built and made famous in 1965 at the New York World's Fair. That was 20 years before the C60 molecule, now commonly referred to as the buckyball was detected.
In the strictest sense of the word you may argue that this example is not really biomimicry since we didn't learn from what existed in nature first and then copy it. While that may be true, it is significant that the properties exist in both the naturally occurring substance and the structure that mimics it.
There is a legend in Santa Fe, New Mexico about a mysterious and ethereal spiral staircase that was built in the Loretto Chapel by an unidentified carpenter who travelled to Santa Fe in the late 1800s. The staircase is considered to be mysterious and ethereal because there is no center support. It is described as an incredible spiral with two complete 360-degree turns. It has no nails or screws of any kind and rests solely by its geometric balance and design. When you look at a picture of this spiral staircase, you immediately think of the double helix of DNA. Is this biomicmicry? What is biomimetic about it is the fact that, similar to the design of DNA, it is structural sound and takes up little space. DNA contains a humungous amount of information about genes and proteins at a nano level in a small amount of space, but because of its spiraling structure (and its ability to be condensed and packaged in this structure) it all fits in the nucleus of a cell. Similarly, because of the small size of the chapel and the height of the loft, conventional methods of building a staircase to the choir loft were not feasible. The spiral staircase mimics the design of the double helix that always existed in nature but of course we didn't know about it at the time. Again, is this an example of biomimicry? I think so.
Biomimicry Present and Future
The process of creating liposomes for the purpose of delivering a drug to a specific targeted area or cell in the body is a form of biomimicry. Enclosed capsules made from a lipid bilayer that has folded over itself mimic cell membranes and is an example of biomimicry. Using what we have learned about how lipid bilayers are formed, using that process to create liposomes, and then filling the capsule with a drug targeted for drug delivery to specific cells can be explained as a biomimedic process.
Creating a liposome and attaching a small piece of a virus to it so that the liposome can enter a cell is another example of biomimicry. Applying what we have learned about the ability of viruses to enter cells for the purpose of manipulating synthetic materials can be explained as a biomimetic process.
A team, led by Ashkan Vaziri, assistant professor of mechanical and industrial engineering at Northeastern; and Myoung-Woon Moon, of the Korea Institute of Science and Technology, created nanoscale and microscale patterned surfaces with adhesion and friction properties similar to that of the gecko footpad. Their hope is to generate applications ranging from adhesives to robotic movement and navigation. The principle of asymmetric adhesion used by many insects and gecko lizards, allows them to move on any horizontal, tilted, or vertical surface. Their remarkable climbing ability can be attributed to the elaborate fibrillar structures that cover their feet. Gecko lizards have one of the most efficient and interesting adhesion devices consisting of finely angled arrays of branched fibers called setae. Gecko toes are covered by millions of hair-like setae five micrometers in size. The ends are tipped with hundreds of spatula that bend and conform to the surface on which the gecko is moving. This is a phenomenon the research team hopes to mimic for the purpose of developing a "smart" adhesive that could adapt to environmental stimuli including a curvy surface or a rough edge. The research team has been experimenting with designing and creating a series of micropillars, (hair-like structures), exposing them to ion beam radiation, resulting in a dual-surface area with unique adhesion and friction properties similar to the properties and function of the gecko footpad. This technology, although not perfected yet, could lead to small high-tech robots able to climb with speed, precision and accuracy on uneven or slippery surfaces and a new generation of smart adhesives equipped to hold strong bonds with any surface. 25 This is a clear example of biomimetics at work for the future.
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