More on biomimetics

[Guest guest]

Pamho, agtSP!

 

This is from Jehova's Witnesses. Very nice article!

 

http://www.watchtower.org/library/g/2000/1/22/article_01.htm

 

COPYING Life's Marvelous Designs

lers tumble and bump their heads. Older children fall from trees and off

bicycles. Athletes crash into one another on the playing field. Motorists

have countless road accidents. Yet, in spite of all these falls, bumps, and

crashes, we often escape without serious injury. We tend to take the

toughness and resilience of our bodies for granted. But as scientists are

beginning to discover, from our bones to our skin, we are the product of

truly brilliant designs.

 

THE combination of strength and toughness—with relatively light

weight—permeates nature. Tender saplings push through cracks in concrete and

rock and force the cracks wide open as they grow into healthy trees. In

turn, trees can withstand winds that topple power poles and rip houses

apart. Woodpeckers bore into wood and subject their heads to forces that

would turn an ordinary brain to pulp. Crocodile and alligator hides deflect

spears, arrows, and even bullets. (Compare Job 41:1, 26.) Such things have

both awed and baffled humans for thousands of years.

 

Over the past 40 years, major leaps in technology have given scientists

powerful new tools to use in studying the secrets behind these designs, most

of which are hidden deep within the living cell. On this microscopic scale,

the quality of design is truly breathtaking and staggering in complexity.

The aim of science, however, is not just to crack the secrets underlying

nature's remarkable materials but to copy them—at least in general

principle. So promising is this field of study that it has led to the

creation of a new science called biomimetics, from the Greek bi´os, meaning

"life," and mi´me¾sis, meaning "imitation."

 

Biomimetics Promises a Better World

 

"Biomimetics is the study of biological structures [and] their functions,"

explains the book Biomimetics: Design and Processing of Materials. It adds

that this study is for the purpose of 'stimulating new ideas and developing

these ideas into synthetic systems similar to those found in biological

systems.'

 

Scientist Stephen Wainwright says that "biomimetics will engulf molecular

biology and replace it as the most challenging and important biological

science of the 21st Century." Professor Mehmet Sarikaya claims: "We are on

the brink of a materials revolution that will be on a par with the Iron Age

and the Industrial Revolution. We are leaping forward into a new era of

materials. Within the next century, I think biomimetics will significantly

alter the way in which we live."

 

In fact, it has already begun to alter our world, as we shall see. But

first, let us look briefly at a few of the as-yet-unfathomed marvels

scientists are busy studying. We will also examine the sobering implications

behind the word "design" and see how these give meaning to the amazing world

around us.

 

LEARNING From Designs in Nature

 

"Many of our best inventions are copied from, or already in use by, other

living things."—Phil Gates, Wild Technology.

 

AS MENTIONED in the preceding article, the aim of the science of biomimetics

is to produce more complex materials and machines by imitating nature.

Nature manufactures its products without causing pollution, and they tend to

be resilient and light, yet incredibly strong.

 

For example, ounce for ounce, bone is stronger than steel. What is its

secret? Part of the answer lies in its well-engineered shape, but the key

reasons lie deeper—at the molecular level. "The success of living organisms

lies in the design and assembly of their smallest components," explains

Gates. As a result of peering into these smallest components, scientists

have isolated the substances that give natural products from bone to silk

their envied strength and light weight. These substances, they have

discovered, are various forms of natural composites.

 

The Miracle of Composites

 

Composites are solid materials that result when two or more substances are

combined to form a new substance containing properties that are superior to

those of the original ingredients. This can be illustrated by the synthetic

composite fiberglass, which is commonly used in boat hulls, fishing rods,

bows, arrows, and other sporting goods.* Fiberglass is made by setting fine

fibers of glass in a liquid or jellylike matrix of plastic (called a

polymer). When the polymer hardens, or sets, the end result is a composite

that is lightweight, strong, and flexible. If the kinds of fibers and the

matrix are varied, an enormously broad range of products can be made. Of

course, man-made composites are still crude compared with those found

naturally in humans, animals, and plants.

 

In humans and animals, instead of fibers of glass or carbon, a fibrous

protein called collagen forms the basis of the composites that give strength

to skin, intestines, cartilage, tendons, bones, and teeth (except for the

enamel).# One reference work describes collagen-based composites as being

"among the most advanced structural composite materials known."

For example, consider tendons, which tie muscle to bone. Tendons are

remarkable, not just because of the toughness of their collagen-based fibers

but also because of the brilliant way these fibers are woven together. In

her book Biomimicry, Janine Benyus writes that the unraveled tendon "is

almost unbelievable in its multileveled precision. The tendon in your

forearm is a twisted bundle of cables, like the cables used in a suspension

bridge. Each individual cable is itself a twisted bundle of thinner cables.

Each of these thinner cables is itself a twisted bundle of molecules, which

are, of course, twisted, helical bundles of atoms. Again and again a

mathematical beauty unfolds." It is, she says, "engineering brilliance." Is

it any surprise that scientists speak of being inspired by nature's

designs?

 

As mentioned, man-made composites pale when compared with those of nature.

Still, synthetics are remarkable products. In fact, they are listed among

the ten most outstanding engineering achievements of the past 25 years. For

example, composites based on graphite or carbon fibers have led to new

generations of aircraft and spacecraft parts, sporting goods, Formula One

race cars, yachts, and lightweight artificial limbs—to mention just a few

items in a rapidly growing inventory.

 

An Extinct Fly Helps to Improve Solar Panels

 

While visiting a museum, a scientist saw pictures of an extinct fly

preserved in amber, says a report in New Scientist magazine. He noticed a

series of gratings on the insect's eyes and suspected that these might have

helped the fly's eyes to capture more light, especially at very oblique

angles. He and other researchers began conducting experiments and confirmed

their hunch.

 

Scientists soon made plans to try to etch the same pattern of gratings onto

the glass of solar panels. This, they hope, will increase the energy

generated by solar panels. It might also eliminate the need for the costly

tracking systems presently required to keep solar panels pointed at the sun.

Better solar panels may mean less fossil fuel use and, thus, less

pollution—a worthy goal. Clearly, discoveries like this one help us to

appreciate that nature is a veritable mother lode of brilliant designs just

waiting to be found, understood and, where possible, copied in useful ways.

 

Multifunctional, Miraculous Blubber

 

Whales and dolphins don't know it, but their bodies are wrapped in a miracle

tissue—blubber, a form of fat. "Whale blubber is perhaps the most

multifunctional material we know," says the book Biomimetics: Design and

Processing of Materials. Explaining why, it adds that blubber is a marvelous

flotation device and so helps whales surface for air. It provides these

warm-blooded mammals with excellent insulation against the cold of the

ocean. And it is also the best possible food reserve during nonfeeding

migrations over thousands of miles. Indeed, ounce for ounce, fat yields

between two and three times as much energy as protein and sugar.

 

"Blubber is also a very bouncy rubberlike material," according to the

above-mentioned book. "Our best estimate now is that acceleration caused by

the elastic recoil of blubber that is compressed and stretched with each

tail stroke may save up to 20% of the cost of locomotion during extended

periods of continuous swimming."

 

Blubber has been harvested for centuries, yet only recently has it come to

light that about half the volume of blubber consists of a complex mesh of

collagen fibers wrapped around each animal. Although scientists are still

trying to fathom the workings of this fat-composite mix, they believe that

they have discovered yet another miracle product that would have many useful

applications if produced synthetically.

 

An Eight-Legged Engineering Genius

 

In recent years scientists have also been looking very closely at the

spider. They are keen to understand how it manufactures spider silk, which

is also a composite. True, a broad range of insects produce silk, yet spider

silk is special. One of the strongest materials on earth, it "is the stuff

that dreams are made of," said one science writer. Spider silk is so

outstanding that a list of its amazing properties would seem unbelievable.

 

Why do scientists use superlatives when describing spider silk? Besides

being five times stronger than steel, it is also highly elastic—a rare

combination in materials. Spider silk stretches 30 percent farther than the

most elastic nylon. Yet, it does not bounce like a trampoline and so throw

the spider's meal into the air. "On the human scale," says Science News, "a

web resembling a fishing net could catch a passenger plane."

 

If we could copy the spider's chemical wizardry—two species even produce

seven varieties of silk—imagine how it could be put to use! In vastly

improved seat belts as well as in sutures, artificial ligaments, lightweight

lines and cables, and bulletproof fabrics, to name just a few possibilities.

Scientists are also trying to understand how the spider makes silk so

efficiently—and without the use of toxic chemicals.

 

Nature's Gearboxes and Jet Engines

 

Gearboxes and jet engines keep today's world on the move. But did you know

that nature also beat us to these designs? Take the gearbox, for example.

Gearboxes allow you to change gears in your vehicle so as to get the most

efficient use out of the motor. Nature's gearbox does the same, but it does

not link engine to wheels. Rather, it links wings to wings! And where can it

be found? In the common fly. The fly has a three-speed gearshift connected

to its wings, allowing it to change gears while in the air!

 

The squid, the octopus, and the nautilus all have a form of jet propulsion

that drives them through the water. Scientists view these jets with envy.

Why? Because they are composed of soft parts that cannot break, that can

withstand great depths, and that run silently and efficiently. In fact, a

squid can jet along at up to 20 miles [32 km] an hour when fleeing

predators, "sometimes even leaping out of the water and onto the decks of

ships," says the book Wild Technology.

 

Yes, taking just a few moments to reflect on the natural world can fill us

with awe and appreciation. Nature truly is a living puzzle that prompts one

question after another: What chemical marvels ignite the brilliant, cold

light in fireflies and certain algae? How do various arctic fish and frogs,

after being frozen solid for the winter, become active again when they thaw

out? How do whales and seals stay under the water for long periods without a

breathing apparatus? And how do they repeatedly dive to great depths without

getting decompression sickness, commonly called the bends? How do chameleons

and cuttlefish change color to blend with their surroundings? How do

hummingbirds cross the Gulf of Mexico on less than one tenth of an ounce [3

gm] of fuel? It seems that the list of questions could go on endlessly.

 

Truly, humans can only look on and wonder. Scientists develop an awe

"bordering on reverence" when they study nature, says the book Biomimicry.

 

Behind the Design—A Designer!

 

Associate professor of biochemistry Michael Behe stated that one result of

recent discoveries within the living cell "is a loud, clear, piercing cry of

'design!'" He added that this result of efforts to study the cell "is so

unambiguous and so significant that it must be ranked as one of the greatest

achievements in the history of science."

 

Understandably, evidence of a Designer creates problems for those who adhere

to the theory of evolution, for evolution cannot account for the

sophisticated design within living things, especially at the cellular and

molecular levels. "There are compelling reasons," says Behe, "to think that

a Darwinian explanation for the mechanisms of life will forever prove

elusive."

 

In Darwin's time the living cell—the foundation of life—was thought to be

simple, and the theory of evolution was conceived in that era of relative

ignorance. But now science has gone past that. Molecular biology and

biomimetics have proved beyond all doubt that the cell is an extraordinarily

complex system packed with exquisite, perfect designs that make the inner

workings of our most sophisticated gadgets and machines look like child's

play by comparison.

 

Giving Credit Where It Is Due

 

In 1957, Swiss engineer George de Mestral noticed that the small, tenacious

burs clinging to his clothes were covered with tiny hooks. He studied these

burs and their hooks, and soon his creative mind caught fire. He spent the

next eight years developing a synthetic equivalent of the bur. His invention

took the world by storm and is now a household name—Velcro.

Imagine how de Mestral would have felt had the world been told that no one

designed Velcro, that it just happened as the result of a string of

thousands of accidents in a workshop. Clearly, fairness and justice demand

that credit be given where it is due. Human inventors obtain patents to

ensure that it is. Yes, it seems that humans deserve credit, financial

rewards, and even praise for their creations, which are often inferior

imitations of things in the natural world. Should not our wise Creator

receive acknowledgment for his perfect originals?

 

Brilliant design leads us to the logical conclusion, says Behe, "that life

was designed by an intelligent agent." Is it not reasonable, therefore, that

this Agent also has a purpose, one that includes humans? If so, what is that

purpose? And can we learn more about our Designer himself? The following

article will examine those important questions.

 

* Strictly speaking, fiberglass refers to the glass fibers in the composite.

However, in common usage the term refers to the composite itself, which is

made of plastic and fiberglass.

 

# Vegetable composites are based on cellulose rather than collagen.

Cellulose gives wood many of its coveted qualities as a building material.

Cellulose has been described as a "tensile material without peer."