What do a kingfisher, cocklebur pods and a Namibian beetle have in common? Besides being living organisms, they have all served as inspiration for creative human technologies to solve challenging problems.
The kingfisher’s sleek beak spurred the streamlined nose design on high-speed trains in Japan. Cockleburs inspired the hook-and-loop fastener system Velcro. And the Namibian beetle’s back inspired a water-collection plant in the desert.
This is biomimicry. It is an approach to innovation, defined by the Biomimicry Institute as seeking: “sustainable solutions to human challenges by emulating nature’s time-tested patterns and strategies.” There are many solutions in nature — and we are learning about more and more of them.
As a researcher in materials science and engineering, I have worked on a variety of different substances. These include biomaterials (implantable ceramics, dental ceramics and titanium alloys) and a variety of different coatings technologies (thermal barrier coatings in turbine engines, corrosion-resistant coatings and catalyst supports).
Biomimicry has helped my teams design solutions that we otherwise would likely not have explored. Inspiration has come from organisms themselves, how organisms make materials and how organisms work together. For example, based on structures observed on plant leaves, we have grown ceramic coatings at room temperature to make oil and water filters on paper and on copper mesh.
How biomimicry works
Without flying insects, birds and floating seeds would we have been able to create airplanes, gliders, parachutes or helicopters?
Watch a maple seed spin to the ground or a dandelion seed float through the air and I am sure you will start asking more questions.
Human beings are generally curious and observant and we have made many innovations by looking to the natural world for inspiration. We seek to understand and then we “copy” existing solutions. The process of biomimicry is also about being curious and observant. We follow a disciplined process to ask questions and seek answers by looking at what is already around in nature.
We first observe functions — what does the organism do? The function can be simple or complex: A dandelion seed floating through the air, or chemical signalling in the body to grow bone. We observe how an organism achieves such a function.
We then determine the mechanisms by which the functions are accomplished — we get to the chemistry and physics of the mechanisms. The final stage is to abstract the natural form, process or ecosystem into another purpose — to mimic for our own use.
It pays to pay attention. In the past, I had a research project to devise new ways to make structured catalysts (coatings that better enable chemical reactions.) The team was processing metal wire mesh — to produce ceramic hair-like structures onto which we were to deposit metallic nanoparticles.
We could fabricate the mesh, but the graduate student came to me one day and said that something “weird” was happening. He couldn’t get the nanoparticle precursor solution (the mixture of chemicals that helps to make the final product) to wet the treated wire mesh. The wire mesh was floating on the water-based liquid.
We did not understand what was going on, and so we looked at the structure in the microscope. We still didn’t understand, and so we looked to nature. I took a trip to our greenhouse on campus armed with a water bottle. The manager showed me a variety of plants that repelled water in fascinating ways, and I squirted water on them to see what happened.
I looked at a variety of plants in the microscope, and found that sugar cane had a similar structure to the ceramic coating.
Hydrophobic (water repelling) coatings, based on the structures of the waxes found on leaf surfaces, are used in many applications — from paints (such as Lotusan brand) to power-generation, where efficiency can be gained by controlling droplet formation in condensers and boilers. By paying attention to how nature behaves, and by getting down to the chemical and physical mechanisms, we are able to create bio-inspired solutions from other materials and for different applications.
Growing bone tissue
In high school, my friend told me about a bone defect in his leg — a big hole in his thigh bone. He was running and his thigh bone fractured, and he collapsed. He awoke in the hospital five centimetres shorter. Why? Because 25 years ago, bone defects couldn’t be repaired very easily and the damaged tissue had to be surgically removed. There was nothing bone-like that could be put in the damaged tissue’s place to grow new bone. His perfectly good leg had to be shortened too.
Today, because of biomimicry, we can repair and regenerate bone tissue — breaking your leg doesn’t necessarily mean you also become shorter! How can we do now what we couldn’t before? We have learned how the body grows bone tissue, and we have been able to induce bone growth by mimicking nature’s processes.
We can now make glass in a lab, implant it, and new bone will grow in its place. Three months later, there is no trace of the glass. It sounds a lot like the “Skele-Gro” potion from the Harry Potter series but without the vile taste! Our innovations were inspired by ourselves – after all, we too are part of nature.
Bioactive glass, a calcium phosphate based silica glass that stimulates material resorption and bone growth, is often used in dental applications for bone grafts. The material is placed in a bone defect and over time, under the stresses and the biological environment, the glass corrodes and signals bone cells (osteoblasts) to attach and proliferate at the surface and form new bone. The implanted glass is completely dissolved and replaced with new bone.
Biomimicry and the future
And what of the future? We are seeing and learning so much more about what happens in the natural world through time and sophisticated research studies that it is difficult to predict what we might learn in the future. However, as we learn more, we discover that we have made gross oversimplifications for many natural phenomena — so we need to remain curious and observant of the natural world and get down to the details, without losing sight of the entire system.
And, since people are pursuing brain machine interfaces, perhaps we may also consider pursing some other fantasies. Tsaheylu of the Na’vi people in the movie Avatar is “the bond” between different animals — a way to feel as one with the ability to act as one. Imagine if instead of mimicking nature we could become one with it instead. I wonder what other secrets we might learn from the kingfisher, cocklebur pods and the Namibian beetle.