THE SPIDER
Ibrahim
B. Syed, Ph.D., D.Sc.
Those
who read the Noble Qur'an must be wondering why Surah, 29 is titled
“Al-Ankabut", or the Spider which is a lowly insect. The word Ankabut is
mentioned in Ayah (verse) number 41 of Sur-ah Z9 as follows:
“The
parable of those who take protectors other than Allah is that of the Spider who
builds (to itself) a house; but truly the flimsiest of houses is the Spider's
house if they but knew."
People
consider spiders are nuisances or horrifying creatures that should be exterminated
whenever possible. In fact, spiders are benefactors of humans. Every year
spiders do away with millions upon millions of insects such as locusts and
grasshoppers that would destroy grain crops, and with such consumers of green
leaves as beetles and caterpillars, as well as with troublesome mosquitoes and
flies. One authority stated in the following words: “If it were not for the
number of spiders everywhere, all living creatures except defoliating
(leaf-eating) caterpillars might face starvation”.
Spiders
keep control of the insects without using the man-made insecticides which are
posing many environmental problems including the decreasing of sperms in the human
male thus resulting in infertility. Therefore, we must appreciate our spider friends
which are performing this service with no ill effects whatever to mankind. They
exist in abundance and they are found almost anywhere. Some types flourish indoors,
and others live outdoors but close to the buildings. In the fields they make
their homes on tall plants and low shrubs, in forests they take refuge under
dried leaves and fallen logs. Any piece of bark or stone may serve as a spider
shelter. We may find them near water and even on it, in dry country, in underground
caves and on mountaintops. Because of ignorance, through the ages, in countless
stories, spiders have been connected with sinister, unhealthy activities and
places. They are treated as sinister and
aggressive
and usually capable of a deadly bite.
The
truth is a spider is a mild creature, most anxious to avoid contact with man.
It bites only when hurt or frightened, and usually will walk over a person's skin
without making any effort to bite. In fact the majority of spiders we come
across are small and because their biting apparatus is not strong enough, they
are not capable of breaking through the skin of a human being. One must be
aware that a large wolf spider will cause no greater pain nor inconvenience from
poison that a wasp usually inflicts. On the other hand a black widow, the only
spider native to the United States which can inflict poisoning of a truly
serious nature upon humans, is small-no more than half-an-inch in length.
Because of this the black widow is always given wide publicity. Black widow
poisoning is often serious, but rarely is it fatal. Very voting children and
adults who are not in good physical condition suffer from it most acutely. If
treated properly and promptly the ill effects usually lessen in a few hours and
after a couple of days rest, the victims will completely recover.
Spider
Silk
The
strength of spider silk, so delicate in appearance, is surprisingly great. A
strand can be stretched as much as one half its normal length before breaking,
and has a tensile strength surpassed only by fused quartz fibers. Fine strands
are stronger than others, the strength to some extent depending on the speed
with which they are drawn out of the spider's body. The greater the speed, the greater
the strength. There are other variations, too. Most of the silken threads are
not single fibers but are made up of two or more strands. A fiber may be as
fine as a millionth of an inch in thickness but more often it is ten or twenty
times as thick, and the grouping of these fibers naturally produces threads of
a variety of thicknesses. Also some fibers are sticky while others are not.
Making
a web is one of the many uses to which the spider puts silk to use. Spiders uses
the silk for trap lines, draglines, ballooning lines, for trap-door covers to under-ground
retreats, for egg sacs and nursery webs, for chambers in which to hibernate or to
mate, for the many types of webs in which food is ensnared, and for entangling and
swathing their prey. Silk for all these purposes is not achieved with one type
of gland; there are at least seven different types that equip the whole spider
group. Some individual spiders have as many as six kinds and possibly have more
than six hundred separate glands; others have less than this.
Analysis
of Silk
The
silk itself is a substance known as “scleroprotein". When produced in the glands
it is a liquid; only when drawn outside the body does it harden into thread. Once
it was though that exposure to the air caused the hardening, but it now appears
that the drawing-out process alone is responsible. To carry forward the work
done by the glands, a spider is equipped with spinnerets, usually six in
number. These are as flexible as fingers; they can be extended, compressed, and
in general be used like human hands. In the “spinning field", where the
spinnerets are grouped, single threads are combined into various thicknesses,
and some of the dry strands may be coated with a sticky substance. Thus a
finished strand may be thin or thick, dry or sticky. It may also have the form
of a beaded necklace. For the latter type the spider spins rather slowly and,
pulling out the sticky thread, lets it go with a jerk. The fluid thus is
arranged in globules spaced along the finished line. The {thread known as the
dragline may be thought of as a spider's “life line" for it acts gas a
lifesaver under all sorts of conditions. No matter where or how far a spider travels, the
dragline goes along, reeling out from spinnerets at the rear of the body. It
forms part of the construction of webs, it holds its little manufacturer
securely in difficult places, it aids in escaping from enemies. For a spider
resting in a web the dragline makes possible a quick drop and hide-out in
vegetation. It enables active hunting spiders to leap from buildings, cliffs,
or any high point complete safety.
Benefits
of Spider Silk to Man
One
may be wondering why the spider silk in contrast to the silk of the silkworm,
is tot of great commercial importance. One reason lies in the varying thickness
of spider thread. Also it is more difficult to work with, and, because it does
not stand up well in the weaving process, it lacks the luster of insect silk.
Besides all this the problems of biasing and feeding large numbers of spiders
are great compared with supporting skin-worms.
Primitive
people like in New Guinea have used spider silk in a number of ways. They make
fishing nets and lures and such articles as bags, headdresses that will keep off
the rain, and caps. These are not fashioned from single strands but from
matted, twisted threads. The primitive natives of North Queensland, Australia,
look to spiders for their fishing equipment. One way they use them is to
entangle one end of a thin switch in a web, then, using a weaving motion, they
twist the coarse silk lines into a single strand which may be more than a foot
long. The strand of silk is then trailed through the same area. As a fish rises
to this bait its teeth become entangled in the invisible strands of silk and it
is easily pulled out of the water. Most fish caught in this matter are no more
than two inches long, but it is claimed that such silken fishing poles can hold
more than half a pound of weight.
Besides
being helpful to primitive people, spider silk has proved useful to the makers
of such complicated instruments as astronomical telescopes, guns and engineers’
levels. The fibers, being very fine yet strong and able to withstand extremes
of weather, are excellent for sighting marks. During the Second World War there
was considerable demand for spider fiber for surveying and laboratory
instruments. The silk would he reeled from the spinnerets of living spiders, then
stored on especially constructed frames until needed. Black widow spiders were
used to a great extent for this silk production, although the common house orb
weavers, the gardens orb weavers and others all help to provide the silk
employed for specialized purposes. One drawback to the use of spider silk in
industry is its ability to age in a humid atmosphere. For this reason filaments
of platinum or engraving on glass plates take its place in such instruments as
periscopes and bomb sights.
Fiber
Engineering
As we know
the orb-weaving spider produces one of the world's toughest fibers. Using
recombinant DNA technology, Dupont scientists in the United States have created
synthetic spider silk as a model for a new generation of advanced materials. It
has been suggested that a single strand of spider silk, thick as a pencil,
could stop a 747 jumbo Jet in flight. Whatever comparison one uses, the
dragline silk of the orb-weaving spider is an impressive material. On an equal
weight basis, it is stronger than steel. In addition, spider silk is very
elastic. It is this combination of strength ad stretch that makes the
energy-to-break of spider silk so high. Simply put, it is the toughest material
known. Spider silk is merely the most dramatic example of a sizable family of
biopolymers possessing a combination of properties that synthetic materials
cannot yet approach. Researchers at Dupont are looking to these natural
materials as paradigms for the design and synthesis of a new generation of advanced
structural materials.
Secrets
of Spider Silk
It is
very important to learn exactly how the spider makes its silk because this
knowledge can serve as the basis for a new generation of materials. Fundamental
to achieving these materials is the ability to control all aspects of the
material architecture, beginning at the molecular level. Recombinant DNA
technology provides a practical route to harnessing the power of the
biosynthetic process to control polymer sequence and chain length to a degree
that is otherwise impossible. A broad range of mechanical properties is
accessible by careful selection of the appropriate building blocks, as more sophisticated
properties that are common among proteins. Advanced computer simulation
techniques to design a molecular model that integrates all the information available
to date about the structure of this amazingly strong and elastic Fiber.
Synthetic genes were designed to encode alleges of the silk proteins. These
genes were inserted into yeast and bacteria and the protein analogs were produced.
The biosilk was then dissolved in a solvent and the protein was spun into
fibbers using spinning techniques similar to those of the spider.
Revolution
through Synthetic Spider Silk
Scientists
are envisioning many possible obvious one. The elasticity and strength of existing
products such as spandex and nylon weight, tough and elastic, biosilk may also
have applications in satellites and aircraft. More importantly, the new
generation of advanced materials that spider silk research may bring about has
the potential to transform our lives in countless ways we can scarcely imagine.
It has been over 52 years since the discoveries of Wallace and Carothers and
his team that the world nylon and ushered in the age of polymers. Initial successes
predict that harnessing biosynthesis will play a major role in the new materials
revolution. Synthetic spider silk may help create super-performing garments of
bridges hung from cables of synthetic spider silk fibers may someday be a
reality. Why Spider's House is Flimsiest of Houses?
Every
Muslim reader of this article has a problem understanding this article because according
to the Noble Qur’an (Surah 29, Ayah 41) cited above the FLIMSIEST of houses is
the spider's house. The scientific studies show that a single strand of spider silk,
thick as a pencil, could stop a 747 jumbo Jet in flight, and that on an equal
basis, the spider’s silk is STRONGER THAN STEEL. All these sound too
far-fetched and incomprehensible and extremely difficult to understand the
mysteries of science. But most important of all this article apparently CONTRADICTS
the verse 41 in Surah 41.
The
quick answer is that per unit weight the dragline silk of the golden orb spider
is one of the world’s toughest fibers. Webs are combinations of many kinds of
spider silk all able to be produced by the same spider. The web radials are
strong, but the somewhat weaker circumferential (quasi-circular concentric)
fibers are elastic and sticky to absorb the energy of a flying insect and hold
it in place. Silk fiibres for victims and offspring encapsulation (cocoons) are
also different. The strongest of all is the fiber which the spider uses for
transport, the dragline silk. In summary the spider produces both strong and as
well as weak fibers and the web it weaves to catch lying insects is weaker and hence
it is referred to in the Qur’an as the FLIMSIEST of houses.
Muslim
scientists and researchers throughout the world should get inspiration from the
Qur'anic Ayat and pursue research in areas that benefit not only Muslims but the
whole of humanity. Biosilk is one such area which needs to be explored by young
Muslim scientists and research workers in the Muslim World.
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