14 DAY TRIAL // Nature's brevets are amazing. Since toddlers, we can fall, hit our heads, experience accidents and yet, in most cases we escape without much damage. At the same weight, a bone is harder than steel, because if their shape and molecular structure. This mix of strength and resistance is encountered everywhere in nature. Small trees spread their roots in concrete and rock rifts which they widen while turning into vigorous trees. Trees can stand storms that break down electricity posts and destroy houses. Woodpeckers carve holes in wood experiencing forces applied to their heads that would smash any normal brain. The skin of crocodiles and alligators rejects spears, arrows and even bullets.
If you thought that optical fibers are a wonder of engineering, you are wrong. First optical fibers were made in 1951, and they caught light, transmitting it in broken lines. But this is an old trick for the sponges living in the Ross Sea (Antarctica). These giant sponges, living up to 30 m (100 ft) deep have spicule like fibers going out of their bodies and capturing and transmitting light under an angle of 90' to the symbiotic algae living inside the body of the sponges. Lateral spicules capture the light falling under other angles.
Latest technological advances allow us to peek into the natural secrets in order to copy and apply these patterns in a science called biomimetics, for new materials and technologies that characterize a new technological revolution in the human history. The composites are solid materials achieved by combining two or more chemicals to obtain a new substance with superior qualities to the initial components. The glass fibers, made of glass and plastic, are a synthetic material employed in making boats, fishing canes, bows, arrows, and other sport items. They are made by inserting extremely thin glass fibers in a plastic material, which can be liquid or gelatinous. When the plastic hardens, it forms the light, hard and flexible composite.
Graphite and carbon based composites permitted the development of new components for planes and spacecrafts, sport items, cars, yachts and light prosthetic materials... But the man-made composites are inferior to the natural ones. Instead of glass or carbon fibers, human and animal composites employ a fibrous protein called collagen that confers strength to skin, intestines, cartilages, tendons, bones, and teeth (except the enamel). Plant composites are based on another fiber: cellulose.
Collagen-based composites are amongst the most advanced known materials. For example, the tendons, which attach muscles to bones. Their strength is given not only by the collagen-based fibers, but also by the remarkable pattern through which the fibers are woven together. The forearm tendons resemble a bundle of twisted cables, similar to those used for suspended bridges. Each cable is in turn, another bundle of thinner twisted cables. And this one a bundle of twisted molecules...
Let's take as an example the humpback whale. An adult individual can weigh 36 tons (79,000 pounds), much the same as a fully loaded truck. Even if it has a pretty stiff body, this 16 m (48 ft) long mammal equipped with extremely long pectoral fins similar to wings is remarkably agile in the water. In fact, these unusually long (no other cetacean, whale or dolphin, had such long fins) and odd shaped fins are the secret. When this whale starts feeding, it swims upward, in spiral, under a shoal of fish or crustaceans that it is going to feast on. The whale starts producing a cloud of bubbles, with a 1.5 m (5 ft) diameter, which pushes the little living things to the surface where the whale swallows them at once.
The upward edge of the fins is not smooth, like a plane's wings (and like the wings of the other whales) but serrated, provided with a row of swells, called tubercles. While the whale is swimming upward, these tubercles increase the whale's ascendant force, defeating the water force exerted on its body. Due to the tubercles, the water flows over the fins, forming a vortex around them, even when the whale rises almost perpendicularly. If the edge of the fins were smooth, the whale could not rise in such tight circles, because under the fin there would emerge froth and water vortexes, and the ascendant force would be low. Plane's wings adopted this model; less flaps and other mechanic devices would be necessary to modify the air flux. Such wings would be more secure and easier to care.
Whale bubbler is another amazing natural material: a floating mechanism, an excellent isolating material in the cold seas inhabited by whales and the best food reserve for long migrations (the same fat amount produces 2-3 times more energy than sugar and proteins). But the bubbler is also extremely elastic, similar to rubber. The acceleration achieved by the elastic turn of the bubbler, which is compressed and stretched with every fluke beat, can save 20% of the energy consumed during the period of continuous swimming. These properties were explained quite recently by the fact that half of the bubbler's volume is represented by a complex collagen web, which wraps any cetacean.
A natural composite "hunted" for long by the scientists is the spider's silk. It is five times stronger than steel and extremely elastic, stretching by 30% more than the nylon (2-4 times before breaking off). Still, it does not vibrate like an elastic web for circus jumps because otherwise it would throw away the spider's food, and it does not get soaked during a rainfall. It was calculated that a fishing web made of spider silk with fibers the thickness of a pencil would stop a passenger plane. There are spider species that can produce even 7 types of silk!
Imagine what we could do if this silk could be industrially made: better security belts, sutures, artificial ligaments, light fibers and cables, and so on. And all this, non-toxic! (no need to mention that many plastic materials can cause cancer, fertility problems, and other health issues). For example, anti-bullet jackets are made of Kevlar, a product obtained using concentrated sulphuric acid, heated up to almost boiling point. The secondary products of the process are extremely toxic and their removal creates issues. Instead, the spider waves its web from proteins with water, at an acidity point similar to the one found in the human mouth.
Studying a fossil fly preserved in amber, scientists saw that the insect's eyes were crossed by some networks which they believed helped the fly capture more light, especially when the light fell under high incidental angles. Subsequent experiments confirmed this. This could be applied to the glass of the solar panels, which could generate more energy and would eliminate the need for tracking systems, which are expensive and head the panels continuously towards the sun.
Nature is also far ahead in the gear box department. The fly has a gear box that connects the body (engine) to, in this case, the wings. The fly has a gear shift working in three speed levels, allowing the insect to change speed during the flight. The gear shift represents in fact a second pair of minute wings that control the movement of the fore wings.
Squid, octopus and jellyfish have a propulsion jet that allows them to speed up in the water. But these "jet engines" have properties that people could not copy: they are soft, do not break, resist to deep depths, and work effectively and noiseless, allowing a squid chased by a predatory fish to reach speeds of 32 km (20 mi) per hour, and even jump a few meters out of the water.
Have you ever wondered about the history of Velcro? Their inspiration came from the little hooks of the thistles and took Swiss engineer George de Mestral 8 years of research, starting with 1957, to develop it.
Wings of the flight devices already mimic the shape of bird wings. Researchers at the University of Florida made a prototype of robot plane, 60 cm (2 ft) long, with a remote control, which has the capacity of a gull to plane, plunge and raise rapidly. The gulls do it because of a great flexibility of their wing articulations. Mimicking this, the plane has a small engine moving a series of metal bars which in turn move the wings. These wings allow the airplane to plane and plunge even between high buildings. Such a high manoeuvrability device could be employed by the Army to detect chemical and biological weapons inside the big cities.
Gecko lizards are amazing due to their capacity of walking on walls and upside down on the ceilings. Lizards' ability to defy gravity and attach to smooth surfaces like glass is due to their setae, hair-like structures of their feet. They do not secret glue, but use weak molecular forces, called Van der Waals, to get stuck to any surface (except Teflon). This creates adherence and thousands of small hairs create enough power to defeat gravitation. Synthetic material imitating this could be an alternative to Velcro and would be extremely useful in medicine to replace chemical adhesives.
NASA intents to make multi-legged robots imitating scorpion's walk, and Fin engineers have already made a 6-footed tractor crossing obstacles like a giant insect. Other teams made a material mimicking the way a coniferous cone opens and closes. A car company works on a vehicle imitating the hydrodinamic shape of the box fishes. Abalone snails are investigated for their shock buffering ability, for developing a lighter and stronger anti-bullet jacket.
Many other amazing traits found in nature are still a puzzle that once solved could revolutionize our lives, like the cold light emitted by fireflies and some algae; how can arctic fish and frogs become active again after freezing during winter; how can seals and whales last so much without breathing and dive repeatedly to impressive depths without experiencing the decompression disease; how can cuttlefish and chameleons change colors and hummingbirds cross the Gulf of Mexico with just 3 grams of fuel?