The parable of those who take to them other than God for guardians (to entrust their affairs to) is like a spider: it has made for itself a house, and surely the frailest of houses is the spider’s house. If only they knew this! (Qur’an, 29:41)

A prehistoric Greek fairytale says a young girl named Arachne was a superb spinner and knitted the most gorgeous cloth. She dared the goddess Athena to a competition. When Athena saw Arachne’s stunning work, she ripped the cloth and hit the young girl. Disgraced, Arachne committed suicide by hanging herself. Athena regretted and transformed Arachne into a spider, so that she could whirl repeatedly and endlessly. Arachnida is the scientific name for spiders. It comes from the young girl in the famous Greek fairytale.

Although usually feared and disliked by people, spiders in fact make life easy for us by feeding on mosquitoes, flies, and locusts, thus saving our crops and eliminate the need for man-made insecticides which pose environmental problems. Besides, spiders are much less dangerous than people think they are; most spiders are keen to avoid interaction with people and will bite only when wounded or scared. Even poisonous spiders are rarely as dangerous as popular myths would have us believe: though black widows are poisonous, and their bites painful, they rarely kill people. If handled properly and quickly the adverse consequences of a black widow’s bite typically diminish in a few hours, and, after a couple of days’ rest or cessation of activities, the victim will fully recuperate [1].

There are countless features of spiders. But their silk is exceptionally unique and this article covers its various aspects.

Spider silk

Biomaterials, having developed over millions of years, frequently surpass man-made substances in their properties. Spider silk is an exceptionally stringy biomaterial which is made almost completely of substantial proteins. Silk fibers have stretchy powers similar to steel and some silks are practically as elastic as rubber on a weight-to-weight basis. In uniting these two properties, silks disclose a hardiness that is two to three times that of artificial fibers like Nylon or Kevlar. In addition, spider silk is also antimicrobial, hypoallergenic, and completely biodegradable [2].

The power of spider silk, so fragile in manifestation, is astonishingly great. A filament can be outstretched as much as one half its normal length before breaking, and has a tensile strength exceeded only by fused quartz fibers. Fine fibers are sturdier than others, the power to some degree depending on the velocity with which they are pulled out of the spider’s body. The higher the speed, the superior the strength.

Most of the silken fibers are not single fibers but are made up of two or more strings. A thread may be as fine as a millionth of an inch in width but, frequently, it is ten or twenty times as dense, and the assemblage of these threads unsurprisingly creates larger threads of a diversity of thicknesses. Furthermore, some threads are gluey whereas others are not.

Scientific research demonstrates that a single thread of spider silk, thick as a pencil, could stop a 747 Jumbo Jet in flight, and that on an equivalent footing, the spider’s silk is stronger than steel, per unit weight. It has been shown that the dragline silk of the golden orb spider is one of the planet’s hardest threads.

Spiders employ silk for webs, but also for trap lines, draglines, ballooning lines, for egg pouches and nursery nets, for compartments in which to sleep through winter or to copulate, and for entrapping and wrapping their victims. Silk for all these objectives is not accomplished with one kind of gland; there are at least seven distinct kinds. A few distinctive spiders have as many as six kinds and probably have more than six hundred independent glands; others have fewer than this [1].

Mechanism behind the formation of spider silk

A batch of scientists headed by researchers from the RIKEN Center for Sustainable Resource Science (CSRS) have scrutinized spider silk and discovered that a formerly undiscovered organizational constituent is critical to how the proteins form into the beta-sheet conformation that gives the silk its extraordinary power [3]. If humans can cultivate equivalents to spider silk, they could be applied in industrial and medical applications. It is well-known that the beta-sheets in spider silk are significant to its strength, but how the sheets are created is scantily comprehended, making it difficult to produce synthetic variations. It is hard to comprehend the process: the silk is originally produced as soluble proteins, which very swiftly crystalize into a solid form.

To explain this, the CSRS scientists obtained silk proteins using genetically altered bacteria that can generate silk from a golden orb-web spider (Nephila clavipes) and then executed multifaceted examinations of the soluble proteins. They discovered that the reiterating area is comprised of two designs – unsystematic spirals and a design called polyproline type II helix. Their investigations confirmed that the polyproline type II helix is critical for the creation of the stiff construction, which can then be rapidly converted into beta-sheets, letting the silk be swiftly intertwined. Fascinatingly, it was discovered that pH – which is supposed to be significant for the molecular exchanges of the N- and C- terminus areas – does not play a significant role of the foldup of the recurring areas, and that it is rather the elimination of water and mechanistic forces through the silk gland.

According to Keiji Numata, who is a project leader of JST ImPACT and led the research group, “Spider silk is a wonderful material, as it is extremely tough but does not contain harmful substances and is readily biodegradable, so it does not exert any harmful load on the environment” [4]. Numata hopes that this discovery may lead to the production of artificial silk that will prove useful for society.

Analysis of silk

The silk itself is a material identified as a “scleroprotein.” When created in the glands it is a fluid; only when dragged outside the body does it solidify into thread. Once it was believed that contact with air produced the toughening, but it currently looks that the drawing-out activity alone is accountable for the change.

To carry out the exertion done by the glands, a spider is armed with spinnerets, usually six in number. These are as accommodating as fingers; they can be prolonged, compacted, and overall be applied like human hands. In the “spinning field,” where the spinnerets are congregated, single threads are joined into numerous compound threads, and some of the dehydrated threads may be covered with a gluey substance. Thus, a completed thread may be thin or thick, dry or sticky. It may also have the look of a bead-trimmed necklace. For the last kind, the spider spins rather unhurriedly and, drawing out the gluey thread, lets it go with a jolt. The liquid thus is organized in beads spread out lengthwise across the completed line.

The strand known as the dragline may be understood as a spider’s “life line” because it performs as a lifeguard in all kinds of situations. The dragline goes along with the spider, no matter where or how far it journeys, winding out from spinnerets at the back of the body. It forms a portion of the building of webs, it grips its tiny builder firmly in problematic places, and it helps in absconding from adversaries. When a spider is inactive in a web, the dragline enables a rapid descent and escape. It allows energetic chasing spiders to jump from buildings, cliffs, or any tall position with absolute security. [1]  

Benefits of spider silk to us

The silk of the silkworm could be very profitable and marketable. There are, however, challenges. One is the changing thickness of a spider’s strand; the other is that it doesn’t well endure the interweaving process. Housing and feeding large numbers of silkworms is not difficult. But housing and feeding large numbers of spiders? There are enormous difficulties.

Native inhabitants of New Guinea have used spider silk in a variety of conditions. They make fishing nets, traps, and such objects as bags, headdresses that will keep away rain, and caps. These are not formed from single threads but from tangled, warped threads. The aboriginals of North Queensland, Australia, look to spiders for their angling supplies.

Spider silk has been valuable to the manufacturers of such complex instruments as astronomical telescopes, guns, and engineers’ levels. The threads, being exceedingly fine but nonetheless robust, are outstanding for sighting marks. Throughout the Second World War, there was a significant demand for spider thread for surveying and laboratory instruments. Black widow spiders were utilized for the manufacture of this silk.

One drawback to the use of spider silk in industry is that it might slump in a moist environment. To overcome this problem, strands of platinum or etching on glass plates take its place in such instruments as periscopes and bombsights. [1]

Spider’s silk also might have healing properties. Due to its antibacterial properties and because the silk is abundant in vitamin K, it may be efficient at clotting blood. Because of the problems in obtaining and handling extensive amounts of spider silk, the largest known piece of cloth made of spider silk is an 11 by 4-foot (3.4 by 1.2 m) fabric made in Madagascar in 2009. Eighty-two persons labored for a period of four years to gather over one million golden orb spiders and extract silk from them. [5]  

Applications of spider silk

As mentioned, human beings have been using spider silk for thousands of years.

The manufacture of contemporary synthetic super-fibers such as Kevlar (bulletproof material) includes petrochemicals, which adds to pollution. Kevlar is also strained from concentrated sulphuric acid. In comparison, the manufacture of spider silk is totally ecologically sustainable. It is created by spiders at ambient temperature and pressure and is strained from water. Furthermore, silk is totally biodegradable. If the manufacture of spider silk ever becomes industrially practical, it could be a substitute for Kevlar and be used to create a varied extent of articles such as: bulletproof vests, wear-resistant lightweight clothing, ropes, nets, seat belts, parachutes, rust-free boards on motor vehicles or boats, biodegradable bottles, bandages, surgical thread, artificial tendons or ligaments, and backings for weak blood vessels. [6]

Synthetic spider silk [5]

Duplicating the multifaceted settings needed to make threads that are similar to spider silk has been difficult to both research and manufacture. Through genetic engineering, Escherichia coli bacteria, yeasts, plants, silkworms, and animals have been utilized to produce spider silk proteins. Yet, these synthetic threads have diverse, simpler features than those of a spider. Manmade spider silks have lesser and unsophisticated proteins than natural dragline silk, and have subsequently half the diameter, strength, and flexibility.

One tactic is to remove the spider silk gene and utilize additional life forms to generate the spider silk. Canadian biotechnology company Nexia effectively produced spider silk protein in transgenic goats that passed the gene for it; the milk made by the goats comprised noteworthy amounts of the protein: 1-2 grams of silk proteins per liter of milk. To make spider silk, Nexia utilized damp whirling and pressed the silk protein across minor extrusion cavities in order to mimic the performance of the spinneret, but this process was not adequate to duplicate the sturdier characteristics of innate spider silk.

In March 2010, investigators from the Korea Advanced Institute of Science and Technology was able to produce spider silk by means of the bacteria E. coli, altered with definite genes of the spider Nephila clavipes. This tactic removes the necessity of milking spiders.

It should be noted that the manufacture of spider silk is not easy and there are intrinsic difficulties. First of all, spiders cannot be cultivated like silkworms since they are flesh-eaters and will merely eat each other if in proximity to each other. The silk produced is very slight, so 400 spiders would be required to make only one square yard of cloth. The other problem is, silk also toughens when subjected to air, which makes working with it problematic.

A different tactic is to study how spiders whirl silk and then replicate this process to make artificial spider silk. The silk itself would also have to be synthetically produced. Chemical production of spider silk is not feasible at present due to the absence of information about the makeup of silk. Randolph V. Lewis, Professor of Molecular Biology at the University of Wyoming in Laramie, has introduced silk genes into Escherichia coli bacteria so that the recurring sections of spidroin 1 and spidroin 2 efficaciously come to form. Others theorize about the likely gene introduction into fungi and soya plants. It may also be possible to modify the silk genes for precise intentions.

Why a spider’s house is the frailest of houses

Spider silk is stronger than steel, but the Qur’an (29:41) states that the flimsiest of houses is the spider’s house. The per unit weight of the dragline silk of the golden orb spider is one of the world’s hardest 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 feebler circumferential (quasi-circular concentric) fibers are flexible and gluey to absorb the energy of a flying insect and hold it in place. The strongest of all is the fiber, which the spider uses for transport, the dragline silk. In summary, the spider fabricates both sturdy as well as feeble fibers and the web it weaves to catch flying insects is weaker; this may be the reason why it is referred to in the Qur’an as the “frailest” of houses.

Conclusions

Scientists are foreseeing many potential uses for biosilk. Textile usages are noticeable one. The flexibility and potency of prevailing merchandises such as spandex and nylon have to be improved. Since it is lightweight, hardy and flexible, biosilk may also have uses in satellites and aircraft. More prominently, the new group of progressive things that spider silk investigation may cause has the prospective to alter our lives in innumerable manners that we can barely imagine. More than 72 years have passed since the inventions of Wallace and Carothers that gave the world nylon that led us into the age of polymers. Artificial spider silk may help produce super-performing clothes of the future. Earthquake resistant suspension bridges hung from cables of synthetic spider silk fibers may someday be a reality. [1]

References

1. Syed, I. B. : Spider Silks http://www.irfi.org/articles/articles_1_50/spider_silks.htm
2. Romer, L and Scheibel, T.: The elaborate Structure of spider silk, PRION, Oct-Dec. 2(4) 154-161, 2008. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2658765/
3. RIKEN Center for Sustainable Resource Science (CSRS). Scientists discover key mechanism behind the formation of spider silk. Materials Science. May 29, 2018, https://phys.org/news/2018-05-scientists-key-mechanism-formation-spider.html

4. Nur Alia Oktaviani, Akimasa Matsugami, Ali D. Malay, Fumiaki Hayashi, David L. Kaplan, Keiji Numata, “Conformation and dynamics of soluble repetitive domain elucidates the initial β-sheet formation of spider silk”, Nature Communications, 10.1038/s41467-018-04570-5 https://en.wikipedia.org/wiki/Riken
5. Service, Robert F. (18 October 2017). “Spinning spider silk into startup gold”. Science Magazine, American Association for the Advancement of Science. Retrieved 26 November 2017. https://en.wikipedia.org/wiki/Spider_silk
6. Vivienne Li, University of Bristol, Spider Silk and Venom. Molecule of the Month – July 2002. http://www.chm.bris.ac.uk/motm/spider/page4.htm

Original Article: Cranford, S.W. et al., Nature 482, 72 (2012).

Spider silk has been a symbol of durability and strength, but the role the design of a web plays or contributes to the strength was unknown. Researchers from Massachusetts Institute of Technology discovered that the impressive design of web and the feature of silk allow spiders to build a super-strong web under different levels of stress. The response of spider silk subjected to load was studied. They studied webs of a variety of species, including European garden spiders and orb weavers, and combined their experiments with correlated web models. At low stress, silk threads soften and extend that result in retaining web structure. At high stress, the silk threads extend and the most stretched ones break. The strength of the silk and the geometry of the web allow only one or two threads being broken under strain. Therefore, the break in the web is minimized and prevents destruction of the whole web. The localized web damage can be repaired by the spider and therefore a requirement for rebuilding the web completely is eliminated. This study shows that spider silk web is very stable even under hurricane winds. This research gives an idea to engineers to build a system that will fail only at small parts of the system under certain stress. Therefore, the system will continue to work just after repairing the destroyed parts of the system. Otherwise, the whole system may be destroyed under potential load and will have to be rebuilt. For example, when a building is exposed to large mechanical stress such as an earthquake, it may be destroyed as a whole and become dysfunctional. Applications on such systems require further research in engineering to achieve structures as stable as a spider’s web.

2- Benefits of Exercise Through a Protein

Original article: Bostrom, P. et al., Nature 481, 463 (2012).

Exercise has a number of beneficial effects in human health such as increasing cardiovascular, respiratory and metabolic capacity. Scientists at Harvard Medical School have discovered a muscle hormone, Irisin, which may be responsible for the many beneficial effects of exercise. Irisin secreted from muscle after exercise and act on white adipose tissue that stores energy. Excessive amounts of white fat cells contribute to many pathologic effects of obesity and diabetes. Irisin, however, converts white fat into the more beneficial and metabolically active brown fat, which burns more calories and produce heat instead of energy. It helps to prevent excessive glucose and fatty acid accumulation in the body. The researchers demonstrated that mildly increased Irisin levels in the blood cause an increase in energy expenditure in mice with no changes in movement or food intake. It also reduces body weight and improves glucose tolerance and obesity induced insulin resistance. This research suggests that Irisin can be a new therapeutic target in human metabolic diseases treatment. Also it could help people lose weight and fight against obesity induced problems such as diabetes and hypertension.

3- New Generation Vaccines with High Efficacy

Original Article: Avci F.Y. et al., Nature Medicine 17, 1602 (December 2011).

Most pathogenic bacteria contain complex carbohydrate structures on their surfaces. These carbohydrates are called capsular polysaccharides. “Glycoconjugate” vaccines are prepared by chemical conjugation of capsular polysaccharides with proteins. This method is the standard design for many vaccines that protect us against common diseases such as pneumonia and meningitis. One drawback with these vaccines is their limited efficacy in populations such as the elderly, children and patients with compromised immune systems. Researchers at Harvard Medical School and Rockefeller University have designed and synthesized a vaccine that is about 100 times more potent than traditional vaccines available today. Until now, the scientific community believed that the body’s professional immune cells, called T-cells, were only able to recognize vaccine’s protein molecules to generate an immune response. However, after studying how glycoconjugate vaccines stimulate immune response, the researchers found that T-cells are also able to recognize the carbohydrate molecules. In a series of elegant experiments, they demonstrated that there is a repertoire of T-cells that can recognize the carbohydrate portion of a glycoconjugate vaccine, and that these T-cells stimulate antibody producing B-cells to generate high affinity antibodies against the carbohydrates. Based on the knowledge obtained from this mechanistic study, researchers have designed a new-generation glycoconjugate vaccine and showed that this new vaccine was about 100 times more immunogenic than a vaccine made by traditional methods.

4- Producing Fuel from Waste with Bacteria

Original Article: Bokinsky, G. et al., PNAS 108, 19949 (December 2011).

It turns out, the secret for alternative source for oil might be hidden in a very common bacterium and plant, E coli and switch grass. As the world’s natural resources are quickly exhausted by humans, new energy sources or alternative energy production methods are needed. One popular way for addressing this question is promoting biofuels. Most of the biofuel source is in ethanol form, often produced from sugar that is extracted from sugarcane and corn. However the consuming of main food sources for energy sources begs a question: What if one day feeding the machines with our food sources makes food scarce? Another concern is that many countries are not using ethanol as an energy source. All these led researchers to pursue another idea: Instead of using food sources as precursor for ethanol, non-food biomass or bio-waste can be converted to precursors for biofuels by utilizing the cellulose or hemicellulose as a starting material. Human body cannot digest cellulose. Hence, cellulose is a bio-waste, which can be broken down into sugar using a mixture of enzymes and subsequently can be used for gasoline production. The enzymes for this procedure can be produced by bacteria in massive amounts. To this end, researchers genetically engineered Ecoli bacteria to consume large amount of cellulose from switch grass and convert it to sugar. Scientists achieved to produce different precursors for different fuels, including gasoline, diesel or jet fuel with bacteria. These are big steps in turning bio-waste into fuels. Imagine one day your plane will be powered with a hay of switch grass and a bottle of bacteria. Next time when you fly over a field of switch grass, you might actually be seeing the next oil well.

from the memoirs of an inventor that lived long, long ago

I especially love when the spider webs shine with the sunrise. The little water beads on them make an extraordinary scene in the early morning. Talking about spiders, how they make their webs is also another beauty. It still blows my mind that they can make such long arches despite their tiny bodies. With the colorful designs on their bodies, spiders are the manifestation of beauty that penetrates even into the smallest holes of the earth. As I am talking about spiders, I would like to tell you a lovely memory of mine about how my admiration of them led me to the discovery of my life.

At the time, there was not much to do other than hunting and picking leaves and fruit. I wanted to do something else. For example, the skins that animals had on them were so fitting, flexible, and nice. We used to take them to put on ourselves; but they did not fit us. They did not cover our bodies totally, and they were stinky. I had a desire to come up with a new way of covering our bodies. I used to sit by the spiders and reflect on this idea a lot while watching them make their webs.

Unfortunately, not everyone was appreciative of the spiders and my interest in them. Whenever my father caught me watching the spiders, he used to mock me and reprimand me for being lazy. He always told me that we needed to get going to hunt something edible, in order not to sleep with empty bellies. You can imagine what torture it was for me to hunt. Killing something of beauty is not beautiful… I knew we had to eat to survive. But maybe I was not the right person to do the killing part. I could cook, I could pick fruit…

One day, when I was watching a spider, I saw a cocoon hanging down from the tree. That was it! The cocoon’s cover was what I was looking for: a large spider web woven densely enough to cover us up. You should have seen me when the idea first came. I couldn’t help but smile so broadly. It had been a long time since I had smiled such a joyous smile. I started running and climbed the hills. To get some rest, I watched the valleys below. Then, once again I took off, and soared down from the hill running; my arms wide open like a bird’s wings.

When I came home, empty-handed to be sure, my mother was not happy at all. “If you don’t want your dad to ruin your night, go and find something before he comes,” she said. Fortunately, I knew some trees that were in fruit just then. I rushed to gather from them to make everybody happy.

Later that night, I had a very scary dream. I was running, and then I suddenly fell into a pit where there was a long snake. The snake started to wind itself around me so that I was totally covered. Then I saw that there was a scorpion in the pit, but it could not approach me because of the snake. Frightened, I woke up screaming. My parents came in to check on me. After a second’s silence, my father said, “I told you not to watch those spiders too much.”

Although I was not really bothered, my parents were getting more and more concerned about me. I was growing to the age of marriage, and they wanted me to have sound spiritual health. The next day, we went to the respected man of God in the village for him to interpret my dream and to get some advice. He said, “The snake in your dream did not harm you. So, it is to be hoped that God will bless you with a cover that is going to protect you from worldly and heavenly harms.” This interpretation was definitely unexpected both by me and by my parents.

Soon after that dream, I talked about my inspiration to my mother, and she told me something invaluable. She said that our great great-grandparents had had beautiful things to wear before they came to this world. When they were sent down here, their beautiful clothes were ripped off. Now that I was thinking about making beautiful garments, maybe this was a heavenly message. Mom wanted me to keep this secret.

I did keep my hopes and inspirations secret, but I did not stop working on them. I was finally inspired by another creature: birds. They made their nests by weaving plants and branches together. That observation brought me to the brim of the discovery of my life, but I was not aware of it at the time.

One day, mom wanted to have a private conversation with me. She said that now I was not a girl anymore but a young woman it was time that I united my life with someone else’s. She said that the guests that had come a few days earlier had come to talk about that issue. They asked my parents for me. At first, I was perplexed to hear all this. I wanted to have some time to prepare myself for the idea. Not long after, the preparations for the wedding were underway, and I was very willing because of the person asking for me.

My groom was the man of God that had interpreted my dream. To suit his status, I wanted to wear something special on the day of the wedding, something never seen before. The days were running by too fast, and bothered by my inability to come up with that special thing, I started spending more time with the spider webs by myself. Mom thought that a gloomy state had befallen on me due to my prospective wedding. She tried to reassure me, calm me, but that was not the case at all. As my state persisted, my parents’ worries grew too. They did not want any trouble in this wedding.

Then one day, I received the first gift for my wedding, before the wedding actually happened. I was inspired to weave the leaves and stems of plants to cover myself just like the winding of that snake in my dream and the cocoon of the spider. With the joy of this heavenly gift, I quickly finished making my garment. This discovery was certainly a heavenly beauty that was sent to celebrate my wedding. With the new garment on me, I was so beautiful, and with the man of my life, I was so happy.

Seth Mette has a PhD in Aerospace Engineering and is currently working as a postdoctoral fellow at West Virginia University. He has a special interest in psychological fiction.

Many of you are frightened of us. You have even invented a disease called “Arachnophobia” (fear of spider). On the contrary, I do not inflict any harm on you, but rather help tidy up nature by catching harmful insects in my web. Particularly, when I remember the honorable task one of my ancestors took part in, my eyes get misty with emotion: In order to save the Prophet Muhammad, peace be upon him, the Pride of the Universe and Humanity, from his enemies, our Lord commanded one of our ancestors to quickly make a web over the entrance of the cave they were hiding in, and this made the infidels stop searching for him there. This honor is enough for us until the Day of Judgment. And please, at least, remember this historical event and stop killing us wherever you see us.

Many of you mistake us for insects. We, the spiders, are different from the insects. The easiest way to differentiate us is to count the number of legs and the parts of our bodies. Insects have six legs, whereas we have eight; their bodies are made of three main parts, while our bodies consist of two parts, one being the head. Moreover, we are different with respect to the sizes and numbers of our eyes. The insects usually have two large compound eyes, whereas we have eight small simple eyes (the simplicity here does not mean ordinary, or lacking in art, it means uncomplicated, plain!).

Those who-in order to reject our Lord-seek a way out through the dead ends of the theory of evolution are stunned when they see the delicate embroidery art in my body and the trap strategy in my magnificent webs. Since they know that we do not have intelligence or conscience, they, helplessly, take refuge in a term called instinct. You can resemble these thinkers to the flies that fall into my trap; the more they struggle through reasoning, basing their theories on nature, or causality, or coincidence, the more entangled they become. In order to deny God, they give credit to some imaginative alternatives for the artwork that has been bestowed upon spiders and thus deceive themselves.

We can live in all continents, except Antarctica, and can survive in many climatic conditions, from deserts to rainforests. The reason that we are more common on oceanic islands than on continents is the special threads we use in our nets. We can use this thread like a parachute and can travel on the wind to far away lands.

One of our most important attributes, the merit of which is so valuable that it is mentioned in the Qur’an, is our silk thread gland that produces thread in various qualities. We use this silk-like substance, which is discharged from conical nipples on our abdomen, for numerous purposes. Most of us are granted with at least two kinds of silk glands, with different structures and secretions. And we are given the knowledge to use these threads for different tasks appropriate to their chemical composition. Since the flexibility, durability, thickness and adhesiveness of each type of thread is different, we use the right type for each task. We use some types of thread to build a web to trap prey, others for furnishing inside our homes, and still others to protect our egg or sperm sacks.

Although everyone knows about our thread, the bio-chemical process that takes place during its production is yet to be completely understood. Our thread, despite being thinner than one thousandth of a millimeter, is five times stronger than a steel string of the same thickness. And it can be stretched up to four times its length. Moreover, it is so light that, despite the great length required to go around the world, such a thread would only weigh 320 grams. My web occupies a large space in comparison to my size; but this appearance is deceptive. My real home is a small spot in the middle; the rest is a trap set up for flies. Now, despite being such a wonderful material, the Holy Qur’an, in the chapter named after me, states that “ The parable of those who take to them other than God for guardians is like a spider: it has made for itself a house, and surely the frailest of houses is the spider’s house. If they only knew this!” (Ankabut 29:41). Have you ever wonder about the inner meaning of this verse? If you have, you can see that it describes my house as being feeble and flimsy, but not the thread that made the house. That means, no matter how excellent is the material you have, if you do not use it in the right place, it is useless. My thread and my house that I build are adequate for me, working as traps for my prey. You might waste the highest quality materials if you use them to construct a building with poor foundations. That is to say, if a human being, equipped with the most wonderful qualities, chooses an invalid fallacious god for themselves, they waste the equipment bestowed upon them, such as intelligence, comprehension and conscience. What is worse, when they adopt a deity other than God, whatever they accomplish in terms of excellent scientific studies, discoveries, or inventions will all be wasted. The arguments of those who deny God might seem sound, but in reality they are fallacies, causing those who are not using their innate capabilities to fall into their traps. Of course, a miraculous book like the Qur’an can be read and understood from the perspectives of other sciences and thus can be understood in a variety of ways. Mine is just one. …

The production of my silk, which is stronger than either synthetic or natural fiber, is similar in part to the production process carried out in factories that manufacture thread. The protein called keratin that I use in silk production is a very common substance, found in human fingernails and hair, as well as in bird feathers, in horn, and in the scales of snakes. Even though the same amino acid is used by these creatures, our Lord, the Creator of all, has the knowledge and the omnipotence to turn the same protein found in your fingernail into silk in my glands.

The liquid silk material, discharged like a protein soup, passes through the ducts of a gland where the liquid is absorbed very rapidly and is then turned into acid by other cells via hydrogen atoms before being spurted out as silk. Once the densified proteins enter the acid pool they form links with one another and turn into thread. The bio-chemical reactions that take place in this process, which I have only explained very basically, vary, depending on the types of thread produced in the different glands; by using different processes different types of thread are produced.

My Lord, Whose mercy is endless, Who gave me all the things that I need to survive down to the smallest detail, has granted me six different manufacturing chambers. In each chamber the chemical substances, prepared as different formulas, are mixed in different proportions to suit my needs; in addition, the caliber of the orifices from which they are spurted and the pressure of the pumps are adjusted to the most appropriate levels to produce thread with different characteristics. Neither my knowledge, nor my ability is enough to comprehend the settings in the silk producing nipples located in my stomach. Nevertheless, the threads that I use for hunting are sticky, while others, by which I return to my home with my prey, are stronger and more flexible. Moreover, the other kinds of thread which I use to wrap my prey are straight and have the quality of becoming harder when movement occurs, while the other threads that I use for my egg sacks have an antibiotic to protect against germs, the ones that I use to go up and down are slippery, and finally the ones I use to lay the foundation of my house are thicker while the ones that I place within the nest are thinner. With graceful leg motions I bring all these threads to the right place and secure them there. I straighten some thread with a comb in my foot. The threads are coated with a liquid substance that protects against fractions in case of exposure to pressure.

A creature that is as small and helpless as I am would need to understand the order of the protein atom used, as well as the properties of pressure in order to protect against fractions, and comprehend the structure of the coating material and many other physio-chemical principles in order to produce these threads that have such excellent qualities. Since that is not the case (I do not have any such knowledge) and as the creation cannot be explained via some unconscious terms such as evolution, mutation, or natural selection, my Creator, the creator of all that I do, is Allah. Plastic surgeons have just started to use some types of spider threads in delicate operations on tendons and joints.

Although I do not have any architectural or engineering training that would help me to calculate where I have to secure my threads or to understand the angles between them, with Divine Guidance I am able to perform these tasks properly. Since I live mostly on insects, I am a very useful animal for you; by catching and destroying many insects I play an important role in the ecological balance. Otherwise, these insects would be overwhelming, not to mention the harm they cause to crops. In addition to this there are some interesting species of ours, which live on fish or even bird.

There are approximately thirty-five thousand species of spiders; of this only five hundred can be considered to be dangerous to humans. Even though all of us have poison glands, if we bite a human in general this only causes an itch. We do not deliberately come and bite humans. Even the most poisonous of us all, the black widow (Latrodectus mactans) is rarely fatal for human beings. This species, which builds a large web with a conical center, can hide around 250-750 eggs, wrapping them up with a silk cover. The females are three centimeters in size, while the males are only about one-fourth the size of the females. Once the females receive the sperm, they eat their males instantly before they can escape. Unlike many of us, the Tarantula (Lycosa tarentula), a spider that measures 2.5 centimeters and which belongs to the wolf spider family that is found in Europe, does not make webs; rather they catch their prey by chasing. They have strong venom as well, but contrary to the common exaggeration, this venom is not fatal. There is another species of tarantula in South America, but this spider belongs to a totally different family, the Theraphosa. The size of the main body of this spider is about 9-10 centimeters, and the distance between the legs is 25-30 centimeters. This large and hairy kind of spider is active at night. Some of them live in holes they have dug in the ground, while others build nests on trees. Even though they can be classified as harmless, their bites hurt. They kill small frogs, lizards, and even birds.

Most spiders live alone. A few of us make houses next to each other, and hunt together. Our hunting techniques are various. The Bolas spider (Cladomelea longipes) has incredible techniques for preparing and throwing bolas. Even though their sense of sight is poor, this species can feel the vibration of flying pigeons and they diffuse a special odor to attract their prey; once the prey has come close, the spider catches it with a sudden attack, paralyzing it with its poisonous bite and then wrapping it in special silk. This special silk has a quality that allows it to keep the wrapped prey fresh; thus, the food, which cannot be consumed in one meal, can be safely stored.

Species that live in the desert dig tunnels in the sand to protect themselves from the dreadful heat, and discharge a special excretion to stick the sand together. They also insulate the interior of the tunnel with silk threads to protect themselves from the heat outside. They make a special silk lid to the entrance of the tunnel and camouflage it with some sand. Then, by stretching their thin thread between some rocks and sticks nearby, they wait for their food. Since the daytime is so hot, they prey at night, waiting for insects to vibrate the threads they have placed.

There are other species, for example, the water spiders (Argyroneta aquatica). This species lives in the water and makes their nests in an air bubble on the water, from time to time traveling up to the surface and restocking the air under their stomach to pump it into their home underwater. Another species, called Dolomedes fimbriatus has legs that enables them to walk on the water and to live on fish. As it is the case with all kinds of Arthropoda (exoskeletal animals), we need to change our skins when we grow. Once the outer skeleton, made of ketone becomes hard, it impedes our growth. Because of that, from time to time, we shed this skin, and grow rapidly while our new skin is soft. Moreover, the legs, which are cut off due to various reasons, are renewed with the grace of God.

I could tell a lot more about my friends, but I think this is enough. I hope that from now on no one will attribute our artful of creation and behavior to evolution or coincidence. In fact, I do not expect such a thing from human beings, who have intelligence, conscience, and comprehension.

Our Creator has solved every potential problem which living things might experience by creating one optimal solution among every alternative.These perfect solutions open new horizons for men, and they also act as guides in the development of science and technology. The book titled “Engineering in Nature” details many striking examples.1

In recent research, it has been discovered how the thread of a spider can contribute to fiber-optic technology. A crucial challenge in photonic technology is to produce the tiny optic fiber that is used as a conductor for a light beam in nano-scaled optic circuits. Yushan Yan, of the University of California in Riverside, has taken an important step forward in this technology by covering the thread from a spider web with a glass-like material and then removing the thread after the material has hardened. By utilizing this technique, it is possible to produce threads that are 1/50000th the diameter of human hair and that have a radius of 2 nanometers (1 nanometer being one billionth of a meter).

Not only will this discovery be applicable in photonic technology, it will also increase the resolution in optical microscopes, or, alternatively, these threads could be turned into nanoscale test tubes in a new breed of sensors that can suck up single molecules of a particular chemical.

A research group at the University of California cut a thread 1 centimeter long from the web of the giant spider of Madagascar, the Nepila Madagascariensis, and pasted the two ends of the thread to a card. Then they repeatedly dipped this thread into tetraethyl orthoslicate solution. After this, the thread that had undergone this process was dried and heated to a temperature of 420 Celsius. The string decreased by one fifth of its original radius and the process resulted in the production of tiny tubes with a radius of one micrometer.

There are plans to make use of the web of the Stegodyphus Pasifiu-a spider which uses a thread of a radius of 10 nanometers and which is found in the Middle East and Southern Asia. This will enable scientists to use thinner fibers. After heating, a thread with a radius of 2 nanometers is attained. Until this latest finding, it was only possible to produce fibers with an interior radius of 25 nanometers.

Fiber optic researchers do not hide their enthusiasm for this new simple and cheap technology. It is expected that it will be used in the field of supra-molecular chemistry; that is the study of very miniature environments. In these environments the reaction-speeds increase and completely different reactions occur. For such experiments carbon nano-tubes are being used at the present time. The tubes made from fibers obtained from spider webs will enable scientists to create more sensitive environments. It is also thought that it will be possible to create microscopes with a higher resolution by using tinier fiber optic catheters.

Such microscopes would be used to observe events that are shorter in duration than the wavelength of light, yet at the same time, these microscopes would not cause the sample to be harmed. Electron microscopes harm the sample since the features of the technology used necessitate this. Currently, these microscopes use a scope that has been made from very thin glass tubes. These fibers are relatively thick, measuring about 100 nanometers in radius. Yet, by means of this new technology, these new microscopes can be developed and biologists will have brand new opportunities to study events that have not been visible before. Surely, it is not possible to say that the immaculate biological structure and incredibly small thread employed by the spider can be explained by simply putting its creation down to chance or by stating that it is a product of nature.

These perfect examples that can be observed in nature will lead to fundamental changes in our understanding of the universe; they will enable great leaps in terms of making our life more comfortable and, most importantly, they will be helpful in realizing how the Divine Power and Art can be present together and be in harmony.

References 

• M. Sami Polatoz, Tabiatta Muhendislik [Engineering in Nature], Kaynak, Istanbul: 2003.
• Danny Penman, Spiders Weave a Web of Light, New Scientist,
• 22 March 2003, p. 20.

Sight: When we look around, we see several shades of colors and hundreds of thousands of images. Human beings, and several animals, are able to see images when light enters the eye and releases an electrical signal through our the nerves to the brain. These signals are then transformed into the images, or pictures, that we see. All creatures see these images differently; some see images in different outlines in shape, color, clarity, circumstances, and distance.

Dogs, because of their hunting needs, see twice as much as do human beings. In addition, dogs have an outstanding ability to follow movement and to perceive direction, speed, and trajectory. Trajectory is what gives dogs the innate ability to plot an angle and predict an angle of movement. For example, dogs have an astonishing ability to know the exact spot where a moving object will land and know from which angle it will be coming. This is the reason why dogs are such good ball and Frisbee catchers; because they visually know the exact point of impact of an object as it falls back to the ground. Cats, on the other hand, have a different reason for being such good jumpers. Cats’ faces are flat between the eyes, a rare feature in the animal world, which makes it easier for them to work together. As a result, a cat can focus sharply and three-dimensionally, an ability that allows it to visually judge distances with great accuracy before jumping.

Rabbits, for example, are one of the few animals that can see all around them (front and back) without turning in either direction. Their eyes are located on the sides of their head, which enables them to see in all directions. Rabbits, frequent preys for predators, are always on the alert, and their eyes are located in the best place to help them see their enemies.

Human beings and wildlife animals have two kinds of vision cells that are located inside the back of the eye: cones and rods. Cones detect colors in bright light, including black, white, and gray. Rods provide sharp vision in dim light, but do not detect colors. Night creatures have more rods than cones, which provide them with sharper vision at night-but with only shades of gray. Also, to assist these creatures in the dark, they have a special layer in the back of their eyes, called the tapetum, which acts as a mirror when light passes through it. If the rod does not detect the light during the first passing, the tapetum reflects the light back to the rod, thus giving the rod a second chance to pick up on the light and see an image. It is this layer that makes some animal’s eyes shine in dim light.

An owl’s eye, for example, is so sensitive in picking up light, that research shows that an owl can follow a trial lit up by a candle 1,000 feet away (3,600 meters).1

Another amazing sight feature is found in predator birds: “telescopic” eyes that allow them to see by making a far away distant object appear larger. Birds such as the hawk and eagle have the sharpest sight of any animal. These birds have about 1.04 million vision cells in the back of their eyes, which that enables them to see a mouse from as far as one mile away.2 (Human beings have only about 130 million vision cells.)3

Although animals are believed to see colors similar to the way humans do, scientists are not sure how bees and insects see color. Scientists believe that, among some other creatures, bees, birds, and insects can see a color that human beings can not: ultraviolet colors. In addition to red, blue, and yellow, flowers often have ultraviolet patterns that show these birds and insects the way to the plant’s nectar and pollen. Such sight makes it possible for these creatures to find and feed on the flowers’ nectar and pollen.

However, not all animals have only two eyes. Jumping spiders, for instance, have eight eyes. There are two big eyes in the front, and six smaller eyes on the top of the head slightly toward the sides. The two front eyes are very well developed and act as a pair of binoculars that give the spider a clear image of objects up to one foot (30 cms) away. The little eyes are called secondary eyes. These eyes can spot moving objects and have a built-in reflecting layer that helps the spider to see objects in dim light. The secondary eyes are the eyes that actually measure the distance the spider needs to jump to catch its prey.

Hearing: Just as with other senses, human beings and animals have different levels of hearing. Most animals have only two ears, which helps all of us locate the origin of a sound. Having two ears helps us locate where a sound comes from. Since sound reaches the ears at slightly different times, this makes a sound louder than in one ear. This difference in volume and arrival time in one ear is an indication as to the origin of the sound. Sound is expressed in hertz (cycles per second), which are repetitive vibrations per second. Adult human beings, with a normal hearing ability, can hear from twenty to twenty thousand cycles per second. Amazingly, wolves can hear up to eighty thousand cycles per second, and dogs can hear up to thirty-five thousand cycles per second, almost twice as many as humans.

Cats have a surprising hearing of between fifty to one hundred thousand cycles per second-three to five times than what human beings can hear. In addition, a cat’s ear has thirty muscles that control the ear muscles that can rotate 180 degrees. This give cats the opportunity to hear its surroundings without moving its head.

An owl’s ear, however, are located at different heights. The difference in height enables an owlit to determine if a noise is coming from a high distance or from the ground. Another interesting feature of many owls is a flat heart-shaped face. The shape of its face functions as a reflector that makes faint sounds louder. These two features enable owls to be the great hunters they are and helps them to hunt in the dark.

Not all animals and insects have “ears”; some have holes in either in their head or in another part of their body, and others have eardrums, such as birds, insects, and fish. Fish’s ears, for example, are located under its skin behind its eyes. This way, a fish can pick up on vibrations that pass their skin under the water. Other fish makes some of these noises by vibrating an internal organ or by rubbing their fins together. Fish use these vibrations to communicate with other fish, to mate, to warn other fish, or to swim together in groups.

Smell: Animals with different smelling needs have been created with different noses and different smelling abilities. Among the different abilities and noses, an elephant’s nose stands out in many individuals’ minds; at least mine. These animals’ noses are so amazingly equipped with different functions, it is surprising. An elephant’s nose (trunk) and upper lip weighs, on average, 300 lbs. (136 kgs.), and can take up and hold more than one gallon (3.7 lt.) of water at a time for spraying on another animal’s back. The trunk is also strong enough to pick up large logs, yet functional enough to gather thin blades to eat. In addition, an elephant can raise its trunk high in the air to smell if any predators are in the area. Another function that I grin at, is that elephants weighing so heavy sink to the bottom of a rivers when they try crossing it; however, they use their noses as snorkels when crossing a deep river by lifting their noses high above the water line to breathe.

Dogs have an astounding sense of smell; they are one of the animals with the best sense of smell. Dogs can pick up odors in concentrations of one part per trillion. A book called Scent, published by veterinarian Dr. Hugo Verbruggen, and dog trainer Milo D. Pearsall, mentions an experiment that illustrates how well dogs can pick up odors. It mentions that if a single gram of butyric acid, a chemical constituent in human perspiration, were released in a ten-story building and evaporated, a human being might be able to smell the odor for a very short moment by sniffing at a window. A dog, in comparison though, would be able to pick up the odor in the same amount if it were to spread over a city the size of Philadelphia anywhere within the city up to an altitude of three hundred feet (90 meters).4 It also mentions that if humans had only ten percent of a dog’s smelling ability that dogs have, we would have a totally different understanding of our world we.

Camels are desert animals that have been created with special channels that can hold moisture in the dry desert. Also, when the wind blows, a camel can close its nostrils to keep out the sand and dust.

Ants also fascinate me. These tiny creatures use odors to identify if an ant belongs in their colony or if it is an intruder. In addition, when an ant dies a certain odor is released, and other ants in the colony will carry the dead ant to a burial site. An experiment has been performed by scientists that placed this “dead” odor on a healthy ant. Although the marked ant was struggling and kept returning to the nest, other ants constantly carried this marked ant to their burial grounds in the belief that it was dead.5

Taste: Taste and smell are chemical senses. Although scientists can only guess what an animal can and does taste, they do know that animals have different taste buds. Taste buds are made up of tiny taste cells that enable us to taste sweet, sour, bitter, and salty substances. Mammals have the most taste buds, while birds have the fewest; insects have none. However, these animals and insects have special taste cells to detect the certain foods they need for survival.

Touch: All animals have a sense of touch. Many scientists believe that touch is the most important sense. The sense of touch indicates if we are hurt, cold, hot, and much more. Blind and visually impaired individuals rely on the feeling of touch to read Braille. Many animals and insects, however, have built-in antennas that help them avoid too close physical contact with other insects and help them detect food and surrounding conditions.

A blowfly (any fly that deposits its eggs on meat or wounds), for instance, uses its antennas to determine if the wind conditions are best for flying. If the wind is blowing too fast, the blowfly will wait until the wind calms down. This is an important feature, for this insect would not be able to survive flying in a strong wind.

Many animals and insects rely on the sensing of vibrations. For example, a spider relies on the shaking of its web to understand if it has caught food or if another spider has come to mate. A spider feels the vibrations through its long legs by waiting at the edge of its web. It is understood that when a spider returns to its web, it shakes the web to see how it vibrates. The results will let it know if something has been caught.

It is also interesting that some animals seek and show affection through touch, just like human beings do. Cats, dogs, monkeys, seals, and lions are some examples that show love and affection. As a cat owner, it is interesting to see the understanding of affection through touch. They enjoy being petted and seek for affection. A question asked by people, who have a cat or have been near a cat, is that why do cats purr and what causes this noise. Scientists believe that purring is produced by blood in a large vein in the chest that vibrates and is then magnified by air in the windpipe.6 Someone petting a cat can actually feel this vibration. Cats usually purr when they are happy or when being shown affection. However, the cat’s purr is more than a sign of content. Kittens, unlike many animals, are born blind and deaf. The vibration of their mother’s purring is a physical sign that the kittens can feel; it is somewhat of a signal to the kittens to be close to the mother and nurse. Also, the kittens’ purr is a signal back to the mother that their kittens are getting their milk and are healthy. This is an extraordinary survival mechanism.

“Super-natural senses”: There are several sensing abilities that scientists can not explain or categorize due to the several unique senses possessed by several animals and insects. Among them is the mosquito’s remarkable sense of heat that leads them to their victims. Female mosquitoes follow have several, however, the most remarkable one is that they can sense temperature differences of less than 1/250th of a degree Fahrenheit. This amazing sense of temperature enables them to land on the warmest and best vein of blood for food.

Another sense scientists have difficulty explaining is that birds, bees, and some other creatures have magnetism. Just as a compass has a magnetic needle that points north, these creatures have natural magnets that help them migrate and find food by using the earth’s magnetic field. They have natural tiny crystals of iron oxide, or also called magnetite, made front iron found in their blood. This enables these adorable creations to still find their way even when they can not see the sun.

People for many years have been puzzled how animals can sense an earthquake before its any “obvious” signs. One of the explanations is that animals, as described throughout the article, have unique and even, in some cases, better senses than human beings. Therefore, they are able to pick up on vibrations, sounds, and odors that humans physically can not, which may indicate to them that a disaster is about to occur.

A final note: Besides their senses, animals have a uniqueness and wondrous superiority over other animals the other with their physical attributes and characteristics. For example, some animals see or hear better than other animals, and some animals have unique physical attributes that other animals do not have. If you look at the beautiful and majestic kingdom of animals, you will find that each animal has a different beauty and awe that deserves much appreciation. This is a component that makes this world a fascinating and perfectly created one.

REFERENCES

1. The National Wildlife Federation “What do Do Animals See, Hear, Smell, and Feel?” (1990).
2. Ibid
3. Ibid
4. Roger A Caras, A Dog is Listening. Summit Books. 1992.
5. The National Wildlife Federation” What do Do Animals See, Hear, Smell, and Feel?” (1990).
6. Arline Bleecker, “Why Do Cats Sulk?” Globe Digests. 1998.

The spider’s web is woven from a special silk. This is a fibrous protein first secreted as a fluid and then stretched into strands which, because of their strength and elasticity, are extraordinarily resistant to breakage.

Garden spiders (Arena diedemata) make their webs from two different silks. The threads of the main structure are woven from a strong silk which can be stretched further (by as much as 20%) but then loses its strength. By contrast, the other kind of silk, used between the main threads, is lighter and stickier and can be expanded three times without losing its original characteristics. Under a microscope drops containing a reserve of silk can be seen at intervals on these thinner ‘hunting silks’.

After its web is complete the spider hides out of sight, somewhere on the outer strands of the web. When an insect flies into the web and struggles, the spider is alerted by the vibrations and runs out. It rapidly contains the victim’s struggle to escape by tying it up with the silk set aside for this purpose in the drops: the elasticity of the hunting silks is vital in this task. While tying it up, the spider injects the victim with the poison from behind its jaws which both paralyses the insect and acts as a digestive juice softening up the now helpless corpse. The spider then goes on injecting and sucking back fluids until the soft parts of the corpse have been digested – any skeletal parts left over are simply discarded.

Spiders put their weaving skills to a number of different uses. As well as making the insect traps we call spider webs, they weave draglines’ that help them to locate themselves and to break their fall if they should slip. Small spiders spin a sort of ‘parachute’ thread that allows them to be carried on the wind.

Some species of spider make active traps. Menneus spins an elastic net between its legs and sweeps it through the air to catch passing insects. Cledomelea dangles from one leg a blob of sticky silk at the end of a long thread and swings it out to attach its prey. Trapdoor spiders (Ctenizidae) dig a burrow closed by a silken door; when an insect ventures near, the spider darts out to capture the imprudent victim.

Spider webs are beautiful, intricate constructions: threads which serve as scaffolding during the construction process are removed once the web, a mesh of sticky and non-sticky lines, has been completed. The skill of producing webs is clearly instinctive, but the irregularity and variety of web forms shows that the skill is adapted by individual species to serve different functions and suit different circumstances – some webs hang in the air to catch insects as they fly, others are laid across the ground, both at angles calculated (presumably by experience) to lure and intercept prey.

Recent research has shown that some A. Glomosus spiders use ultraviolet rays to attract their prey. In one experiment fruit flies (Drosophila) were set free between two webs lit up by a white beam. One web was that of a A. Glomosus spider and radiated ultraviolet rays; the other was not: the flies were attracted to the former

Another remarkable species are the Dolmedes spiders which have long legs (8-10 cm) and striped, brown bodies. They live near water ponds where they have learnt, despite having very poor sight, to catch fish. Their hunting-gathering technique is of awe-inspiring dexterity and patience, rivaling that of any human fisherman. First the spider walks around on the bank to pick a site suitable for laying a web. Once that is done, it waits patiently, standing partly on water and partly on land. A special sticky secretion helps secure its hold on the surface of the water. While waiting, it prepares its poison in its mouth. When a small fish happens by, the spider plunges forward to seize it, releasing its poison into the water as it does so. As the poison begins to work, the spider turns over making its own body a sort of float for the struggling fish, carries it to land and there consumes it.

Some species of spiders do not make webs to ensnare their prey. Instead, they actively pursue their prey or lie in ambush for it. They are endowed with specially keen sight or touch sense, used respectively for hunting in daylight or in the dark. The ambushing varieties are remarkably well camouflaged – the colour and shape of their bodies making them almost invisible against the immediate background of leaves or bark or stones and sand.

One of the night-hunting spiders of the Amazon jungle spends the day hiding in crevices or in holes in trees, emerging into the jungle at night to stalk its food. Its legs spread the width of a human hand and move with utmost stealth until, when near enough, the spider makes a sudden, final dash, seizing small mammals (humming-birds, for example), stunning them with its poison, then dragging and shaking them to death. The detestation and horror this species arouses in human beings is hardly justified – its poison is not more troubling to a human than a bee sting.

Reputation and significance

Spiders have a very negative image among human beings. Perhaps the number of legs, the grotesque facial expression, the hairiness of some species, the fact that they carry a poison, but most of all, the fact that they hide in corners and come out unexpectedly – have contributed to the spiders’ bad reputation. The poison of spiders, with just two exceptions (the ‘black widow’ and the ‘brown recluse’), is relatively harmless to humans.

Spider silk cannot economically be converted into silk cloth for human use. However, it has been used for the cross-hairs of optical instruments. More recently, the silk of the tropical species Nephila has been employed in the manufacture of bullet-proof jackets. The Nephila spin huge webs strung across trees, as long as 2 metres or more, and of a silk so strong and elastic that the local peoples make very effective fishing nets from it.

On balance, it is high time human beings overcame their irrational detestation of spiders. We should be grateful to them for all the good they do for us in preserving our persons and properties, especially our crops, against devastation by insects. One authority calculated the spider population of England and Wales as of the order of 2.5 billions at any one time. This means that if (at a most conservative estimate) each spider eats 100 insects a year, then the total number of insects consumed by spiders is 250 billions annually.

REFERENCES

‘Spiders’ Microsoft (R) Encarta. Copyright (c) 1994 Microsoft Corporation. Copyright (c) 1994 Funk & Wagnall’s Corporation.

Buton, M. & Buton, R. (1975) Enevlopedia of Insects and Arachnids, BPC Publishing Ltd, London.

Gerald, L. & Wood, F.Z.S. (1982) The Guinness Book of Animal Facts and Feats, Guinness Superlative Ltd, London.

Waterson, AR. (ed.) (t975), Collins Enevlopedia of Animals, William Collins Sons & Co Ltd, London and Glasgow.

SPIDERS IN GUINESS BOOK OF RECORDS

The largest and the heaviest spider: The Guyanan ‘bird-eating’ spider (Theraphosa

blondi) of South America has long been credited with the ‘largest spider’ title. A male specimen with a leg-span of 254mm (10 in) and a body length of 89mm (3.5 in) weighed just under 57g (2 oz).

The smallest spiders are the midget spiders (Symphytognathidae), the tiniest of which is the pale yellow Patu marplesi of Western Samoa, S.W. Pacific. A male specimen found in moss at an altitude of 610m (2000 if) measured 0.43mm (0.07 in), which means it is half the size of a full-stop on this page!

The largest spider webs are the aerial ones spun by the tropical orb weavers of the genus Nephila. Several examples found in the Karrakpur Hills near Monghyr, central Bihar, India measured 1.5m (5ft) in diameter (about 4.79m (1 5ft 9in) in circumference) and had long supporting guy-lines up to 6.1 m (2Oft) in length.

The smallest webs in the world are the aerial ones spun by midget spiders. That of the orb weaver Chasmoeephaion armaturn of New Zealand measures about 9-10mm (O.35-0.39in.) in diameter which means it is half the size of a small postage stamp.

The highest speed recorded for a spider on a level surface is 53cm/s (1 .73ft/s) (= 1.90km/h; 1.18 miles/h) for a female house spider, Tegenaria atrica. This may not seem very fast, but the spider covers a distance equivalent to 330 times its own body length in ten seconds.