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Contents Introduction Three waves in sustainable design Problems associated with sustainable design Biomimicry/biomimetics/ bionics Lifecycle approach Cradle to Cradle protocol The transition initiative movement Dematerialization Conclusion

Biomimicry/biomimetics/bionics

A bird is an instrument working according to mathematical law, which instrument is within the capacity of man to reproduce with all its movements. (Leonardo Da Vinci, 1511, cited21)

Humans have for centuries looked to nature for examples of how to improve the objects they design. Many terms have been used to describe the processes used to do this; amongst them the most common are biomimicry, biomimetics and bionics.

The word "bionics" was conceived by Dr. Jack E. Steele of the US Air Force and made public at a scientific meeting in 1960. Bionics means "the use of biological prototypes for the design of man-made synthetic systems. To put it in simpler language: to study basic principles in nature and emerge with applications of principles and processes to the needs of mankind."22 When he wrote this in 1971 Papanek noted that "virtually nothing has been written in the area of bionics."23 However he does list a number of examples of bionics including General Electric's Sidewinder, a heat-seeking missile based on the temperature sensing organs found in rattlesnakes used to detect prey, and also radar and sonar systems which mimic the echo-location device used by bats.

Leonardo Da Vinci based many designs on birds

Bats can navigate entirely by sound. They emit high-pitched sounds between ten and twenty times a second that bounce off objects in their path and are picked up by their extraordinarily sensitive ears. The faster the sound returns the nearer the object is to them, a system allowing them to find their way in pitch dark unhindered. Scientists have used echo-location to find objects under water, i.e. sonar systems, and to locate objects in the air, i.e. radar. In the case of sonar, for example, the sound waves hitting the sea bed or other objects produce echoes which are picked up by machines, and the time taken for the sound to bounce back is recorded, allowing the distance to the bottom of the ocean to be calculated. The same principle has been used to design a walking cane for people with sight problems. In this case laser-beams are sent out of the cane at three different heights to detect objects in the path of the walker. Depending on the height of the object a different sound is emitted.24

The term "biomimetics" was coined by Otto H. Schmitt in 1969 from bios, meaning life, and mimesis, meaning to imitate.25 The term has been used mainly in science and engineering, whereas the term bionics comes from biology and has more recently been used in the world of medicine where its principles have been used to assist with the production of replacement organs and other body parts. The distinction between the terms biomimetics and biomimicry at first appears difficult as many examples used are the same; however, biomimicry has been put forward as a method of working towards sustainment.

Microscope image of a new adhesive material inspired by the soles of insects' feet

Janine Benyus has written extensively on the topic of "biomimicry," which she defines as "innovation inspired by nature."26 She states that "Biomimicry is the idea that studying the models, systems, processes and elements of nature will offer sustainable design solutions to human problems."27 Bionics, biomimetics and biomimicry all follow nature for design ideas. Benyus uses biomimicry to promote the concept of learning from nature as a possible methodology for sustainable design. "To be truly sustainable," Benyus explains, "designs have to both mimic biological material-efficient forms and follow nature's manufacturing rules."28 By copying nature's methods of manufacture it is expected that less energy will be used.

Benyus asks us to treat nature as "Model, Measure, and Mentor." We take models from nature, for example a leaf and how it photosynthesizes, to solve a human problem in producing the solar cell. As a measure we look to nature to see what is possible and what works; for example spider silk is stronger than steel. And when looking at nature as a Mentor we accept it as a teacher and learn from it. There are different levels that we can engage with biomimicry. These are form or function (for example: Velcro mimicking burrs on fur), the process level (as with coating manufacture resembling seashell growth) and also the systems level, closed-loop lifecycles where outputs and by-products become inputs for something else. This has been called "waste equals food" by Cradle to Cradle authors McDonough and Braungart and will be examined more closely later on in this Guide.

One of the examples of biomimicry that Benyus mentions frequently is that of trying to fathom the secrets of spider silk. Christopher Viney is one of many scientists attempting to uncover this mystery. He has been studying the Golden Orb Weaver Spider (Nephilia Clavipes) which produces six different types of silk for a number of purposes from snaring pray to attracting members of the opposite sex. It turns out that the spider can manufacture a silk that is a composite, i.e. two types of material in one. As Benyus says, "Compared ounce for ounce with steel, dragline silk is five times stronger."29 The silk has a unique molecular structure composed of long amino acid chains forming protein crystals; these are embedded in a rubbery matrix of organic polymer. The rubbery constituent makes the silk elastic so it can catch insects that fly into it without breaking. This material is produced inside the spider's body by special glands and is then squeezed through a series of nozzles (spinnerets) at the rear of the spider's abdomen. It is not entirely clear what happens in the nozzles as a soluble liquid protein enters the nozzle and what emerges is an insoluble fiber. What the spider is doing is making a fiber that is stronger than Kevlar, the material used in bullet proof vests, and it is doing it at body temperature. For humans to make Kevlar, high temperatures and sulfuric acid are involved producing toxic byproducts along the way. If this mystery can be solved a number of manufacturing processes can be improved saving energy and waste products as well as creating a wealth of new product possibilities.

Spider webs are the inspiration for numerous materials

The example of spider silk research highlights the benefits, in terms of saving energy and minimizing waste, that can be obtained by understanding natural processes. In this way it is helpful to examine the manufacturing process of a product itself from an industrial ecology perspective, i.e. to look at the system of production as a whole. In this way the process of the product's inception, production and use and finally its end of life are regarded as its lifecycle.

Go To Lifecycle approach