Most of us have taken, or at least interacted with, medicine at some point or another in our lives. This can range from more “simple” over-the-counter drugs to more complex medicines specifically designed for exact illnesses. Considering the Covid-19 era we are going through and as search for a vaccine is at the highest possible speed, it is important to have at least a general idea on how medicines are developed for our use. This article aims to explore how a complicated mix of chemical compounds in a laboratory end up as pills on a shelf in your local pharmacy. We will also explore a brief history of pharmacology, where drugs get their names, how drugs come into fruition, the various affects that drugs can have on our bodies, along with the discrepancies that exist between them in regard to when, how, and why they should be taken.

Pharmacology is the study of the interactions that occur between a living organism and the chemicals that affect normal or abnormal biochemical functions. It includes the study of how a drugs can affect our biological systems, such as individual organs or an entire part of the body, and how the body overall responds to the drug. The discipline encompasses the sources, chemical properties, biological effects and, therapeutic uses of drugs. Substances with medicinal properties are considered pharmaceuticals, whereas drugs given for therapeutic purposes are usually called medications. Drug therapy, which is also called pharmacotherapy, is the use of drugs to prevent, diagnose, and treat signs, symptoms, and disease processes. When prevention or cure is not a reasonable goal, relief of symptoms can greatly improve quality of life and the ability to function properly on a day-to-day basis. Developing an understanding of this craft can allow us to better appreciate how molecules interact to form the drugs and medicines that can change our lives, and perhaps even allow us to contemplate their complex creation and existence.

In its most simplistic definition, a medication is a substance that is ingested or placed onto the body in order to cure a disease or condition (antibiotics are given to cure an infection), treat a medical condition (anti-depressants are given to treat depression), relieve symptoms of an illness (pain relievers are given to reduce pain), given to prevent diseases (flu vaccine helps to prevent the person from complications of having the flu).

Source of drugs

Historically, drugs were mainly derived from plants, animals, and minerals. Morphine, insulin, and iron are all commonly used examples of their respective sources. Belief in the curative powers of plants and certain substances rested exclusively upon traditional knowledge. But empirical information was not subjected to critical examination. Until the end of the 19th century, medicines were made by natural organic or inorganic products including mostly dried or fresh plants and their parts. These compounds might contain substances that possess healing properties or reactions that exert a toxic effect. It is important to remember that many fruits, vegetables, and plants still possess great power despite not having a “modern” origin.

Most drugs used nowadays are synthetic chemical compounds manufactured in laboratories which are synthesized by altering the chemical structure of an existing drug. The first drug of a particular group of drugs are called prototypes. For example, morphine is the prototype of opioid analgesics, and penicillin is the prototype of antibacterial drugs. Drug classifications and prototypes are defined and most new drugs can be assigned to a group. We must be hopeful and continue to search far and wide for cures for all  diseases, whether they be organic or synthetic, since our world is full of an infinite amount of possibilities and discoveries.

Drug names

The systematic naming of pharmaceutical drugs is called “drug nomenclature.” Drugs primarily have three types of names: chemical names, generic names, and trade names. The chemical names are the scientific names that often sound complex and are based upon the molecular structure of a drug. During development, the company will apply for regulatory approval of the drug by the relevant national regulatory agency, such as the U.S. Food and Drug Administration (FDA), and will be granted a generic name for it. Generic names usually indicate, via their stems, what drug class the drug belongs to. For example, oseltamivir is an antiviral drug because its name ends in the -vir suffix.

After development, testing, and regulatory acceptance of a drug, the pharmaceutical company gives the drug a trade name, which is a standard term in the pharmaceutical industry for a brand name or trademark name. Many drugs have multiple trade names which can reflect separate marketing strategies in different countries, manufactured by different companies, or both.

Drug investigation

A new drug investigation is the beginning of the journey of a chemical compound to a drug that will be used in clinics. The testing process of a chemical compound begins with animal studies to determine potential beneficial uses and also potential toxic side effects of the candidate compound.  The results from these animal studies are reviewed, and if the results are satisfactory, the compound then undergoes clinical trials in humans that people can voluntarily sign up for. Most clinical trials use a randomized, controlled experimental design that involves selection of subjects according to established criteria, random assignment of subjects to experimental groups, and administration of the test drug to one group and a control substance to another group.

Patent protection

New drugs that are developed by pharmaceutical companies will be covered under patent protection. This means that only the pharmaceutical company that holds the patent is allowed to manufacture, market, and eventually profit from the drug. This is seen as a return on the company’s investment that it took to develop the drug, which may require years of work and millions of dollars, along with an incentive for developing other drugs. Other pharmaceutical companies cannot manufacture and market the drug during the patent period.

Usually, the drug patent is awarded for around twenty years in the United States, however the number of years varies across countries and drugs. Pharmaceutical companies apply for a patent long before the clinical trial period even begins. The effective patent period after the drug has finally received approval is often around seven to twelve years. After the patented period expires the drug can be manufactured and sold by other companies. The drug is referred to as a generic drug at this point, and they are required to be therapeutically equivalent and much less expensive than trade name drugs.

Pharmacoeconomics

Pharmacoeconomics involves all of the costs that are accrued due to drug therapy and experimentation including those related to purchasing supplies, dispensing the drug, storing it, administrative fees, laboratory and other tests that are used to monitor patient responses, and losses from expiration. The length of a patient’s illness or hospitalization is also considered. While the most important factor is the health of the patient the costs for treatment are increasingly being considered as a major factor when choosing medications, and research projects that compare costs have greatly increased in recent years. The goal is to make it easier for patients to choose the most cost-effective drugs that combine high quality treatment at an affordable price. For drugs or regimens of similar efficacy and toxicity, there is considerable pressure upon doctors and pharmacies to prescribe less costly drugs for shorter duration.

Prescription and non-prescription drugs

In many countries, consumers have two legal routes of access to therapeutic drugs. One route involves a prescription or order from a licensed health care provider, such as a physician, dentist, or nurse practitioner. The other route is by over-the-counter (OTC) purchase of drugs that do not require a prescription. Both of these routes are regulated by various drug laws that change from country to country. Acquiring and using prescription drugs for non-therapeutic purposes, by persons who are not authorized to have the drugs or for whom they are not prescribed, is illegal.

The rejection of drugs in modern society

Nowadays, there are some people who deny various kinds of treatments because of their religious beliefs. This category of people is only a minority, as the majority of religions advocate for people to be healthy and to take care of their health as much as they can. In almost all belief traditions, the human body is believed to be a trust, and in case of any disease, the most appropriate and fastest treatment methods should be used. Even substances that are not normally permitted are allowed by scholars to be used if the person’s safety is concerned. For believers, the most important goal in life is to worship God, and for this to be possible the body must be healthy.

One day, people asked Prophet Muhammad, peace be upon him:

“Should we make use of medical treatment?”

He replied: “Make use of medical treatment, for God has not made a disease without appointing a remedy for it, with the exception of one disease, namely old age.”

People are encouraged to seek out those remedies and to use them with skill and kindness. Let us also remember that Jesus, peace be upon him, too, was very active in his ministry of healing. He showed by God’s permission miracles like curing the blind and the deaf, and bringing the dead back to life. Thus, religions do not refuse treatment with any available methods, and they even strongly encourage treatment and prevention of diseases.

Religions are also well known to treat stress, which wreaks havoc on the mind and body. It is still not known exactly how stress harms our health, but researchers have found that chronic psychological stress is associated with body’s losing its ability to regulate the inflammatory response. It has been shown that the effects of psychological stress on the body’s ability to regulate inflammation can promote the development and progression of disease. We know that religions and beliefs give people hope and significantly decrease the stress.

Human beings are the most precious creation, and health is necessary for us to achieve the purpose of our existence. Using scientific medicine together with faith and religion can help people to protect their health. Being the science of drugs and by investigating new drug therapies, pharmacology helps us exactly with that.

History of Pharmacology

Claudius Galen (129–200 A.D.) was the first person who attempted to consider the theoretical background of pharmacology.

Ali al-Tabari (838 A.D.) Medieval Islamic physicians used natural substances such as Papaver somniferum Linnaeus, poppy, and Cannabis sativa Linnaeus, hemp as a source of medicinal drugs. Although poppy had medicinal benefits, Ali al-Tabari explained that the extract of poppy leaves was lethal, and the extracts and opium should be considered poisons (4).

Theophrastus von Hohenheim (1493–1541), also known as “Paracelsus”, began to question doctrines from antiquity. He prescribed chemically defined substances with such success that professional enemies had him prosecuted as a poisoner. Against such accusations, he defended himself with the thesis that has become an axiom of pharmacology:

“If you want to explain any poison properly, what then isn‘t a poison? All things are poison, nothing is without poison; the dose alone causes a thing not to be poison.”

Johann Jakob Wepfer (1620–1695) was the first to use animal experimentation for pharmacological or toxicological actions.

Rudolf Buchheim (1820–1879) founded the first institute of pharmacology at the University of Dorpat (Tartu, Estonia) in 1847, which firstly made pharmacology as an independent scientific discipline. In addition to a description of effects, he strove to explain the chemical properties of drugs.

Oswald Schmiedeberg (1838–1921), together with his many disciples, helped to establish the high  reputation of pharmacology. He partnered with pathologist Bernhard Naunyn (1839–1925) to found the first journal of pharmacology, which has since been published without interruption.

After 1920, the pharmacological industry had their own pharmacology laboratories outside established university institutes. After 1960, departments of clinical pharmacology were set up at many universities and in industry.

References

1. Clinical Drug Therapy: Rationales for Nursing Practice – Seventh 7th Edition, Lippincott Williams &Wilkins.
2. Basic&Clinical Pharmacology, 12^th Edition, McGrawHill Lange.
3. Modern Pharmacology with Clinical Applications, Sixth Edition, Charles R. Craig and Robert E. Stitzel, Lippincott Williams &Wilkins.

Despite that, there are more than 100 types of amino acids found in nature; only 20 of them are employed for protein synthesis. Among these 20 amino acids, excepting glycine, which does not display chirality, only the L-form of the 19 is used for protein synthesis. This is because ribosomes, where protein synthesis occurs, do not feature the utilization of D-form amino acids. As nothing in the universe exists in vain but with multiple tasks, D-amino acids have a job in the maintenance of life after protein synthesis in very different fashions. The way D-amino acids are employed in the execution and control of physiological preferences amazes scientists.

Up until recent times, D-amino acids were believed to be synthesized mostly by bacteria and plants, unlike mammals, and were considered dysfunctional as they passed, via consumption of nutrients, from bacteria and plants. However when D-amino acids were noticed for having roles as important as L-amino acids during the 1990s, the field gained significance. It was demonstrated that D-amino acids were found widely in invertebrates, vertebrates, and humans as free forms or inside proteins, undertaking critical functions in the nervous and endocrine systems. The most interesting point is the conversion of amino acids from the L-form into the D-form after the protein synthesis occurs in the peptides that are present in the venomous secretions of various animals. This conversion leads to the alteration of the peptide identity and function. Racemase and isomerase (epimerase) enzymes are utilized as they are created for this task. Usually, one or two amino acids of the D-form peptides are in D-form.

When chemist Gunther Kreil of the Austrian Academy of Sciences learned about the use of South American poisonous tree frogs (Phyllomedusa sauvagei ) during Shamanic hunting ceremonies by local Peruvian tribe (Matses), he studied this poison in detail. Participants of the ceremony first caused a burn on their chest region, then applied the poison they obtained from the frog skin over it. Diarrhea and tachycardia started within a minute, followed by a brief faintness. Once they recovered after a few minutes, they were to find themselves in a much more vigorous and exhilarated state of mind. The poison they were applying to their chest contained the dermorphin peptide, which has psychoactive, hallucinogenic effects and a D-amino acid. This peptide is a pain killer 30-40 times more effective than morphine. Among the 7 amino acids found in this peptide (heptapeptide), all are in L-form, except for one. Only the alanine, as the second in the peptide sequence, is in D-form and is produced via the isomerase enzyme from the L-alanine after the protein synthesis. G. Kreil discovered this D-form synthesizing enzyme in 2005. When this peptide was synthesized artificially in the laboratory, it did not display any biological activity or hallucinogenic effect. After a careful investigation of the case, it was found that frog skin based peptide had a D-form alanine second in its sequence; however, the one produced in laboratory had an L-form alanine. It was the presence of only one D-amino acid that made the difference in discovering the identity and function to the natural peptide in the poison.

In recent years dermorphin has started to be used as an illegal performance enhancer during horse races because of its pain killer feature. Horses on dermorphin can run longer and faster since they cannot feel the pain related to foot fatigue.

P. Kuchel of Sydney University also showed a D-amino acid presence in the peptide structured of the poison in the Platypus, a semiaquatic egg-laying mammal. Males use this poison as a weapon to fend off competitors. In 2009, Matthew Waldor and his friends at Harvard University discovered that the sugar-protein mix (matrix) called peptidoglycan found in the composition of bacterial cell walls is structured in a way to contain primarily D-alanine, D-methionine, and D-leucine. More interestingly, D-amino acids of the peptidoglycan structure were able to play a stimulatory role in coordinating the activities of other bacteria in the colony. For example, they acted as light houses in the use of florescence and helped in the formation of thin layers (bio-films) on various surfaces in bacteria. Once we understand the way D-amino acids help in communication between bacteria, it will be possible to use them as a drug. It’s possible they can be used to disintegrate bacteria that forms on teeth, in the lungs of cystic fibrosis patients, on clogs in fuel lines and water tanks, and in medical devices such as catheters.

D-amino acid containing peptides found in lobsters help maintain salinity levels and facilitate courtship in mating seasons. In recent years, D-amino acid containing antimicrobial peptides were discovered (bombinines) in the secretion glands of fire-bellied toad skins (Bombina sp). In this peptide, the second amino acid was in the D-form (D-allo-isoleucine). Two different peptides were found containing D-amino acids in the second position of the amino acid sequence of the poison secreted by Platypus males.

One of the reasons for D-amino acids to exist in animal poisons is that peptides containing D-Amino acids can not be easily degraded by the proteases (peptide bond breaking enzyme) of the host or opponents. Even though proteases can quickly and easily digest proteins composed of L-form amino acids, they struggle to do so with peptide bonds between D and L form amino acids. Pharmaceutical companies are trying to add D-amino acids to the peptide-structured drugs to prevent the quick degradation of peptides and proteins used for treatments when ingested. However, the addition of a D-form amino acid brings the high possibility of a situation that changes the function of a peptide or protein, or causes the loss of a protein. Nonetheless, specialists in this field point out that at least some amount of the D-amino acids that are produced by trillions of bacteria found on the skin, in the digestive track, and among other parts of the body can still be utilized for human health and convenience.

The D-serine of the mammalian nerve systems (glial cells and neurons), the D-aspartate of the neuro-endcorine, endocrine tissues, and testicles, and the D-alanine and D-aspartate amino acids of aquatic animals are abundant. D-Serine in the brain is synthesized by the conversion of L-serine into D-serine by the serine racemase enzyme. D-aspartate is in charge of hormone synthesis and secretion, and the regulation of spermatogenesis, and is produced by aspartate racemase and degraded by D-aspartate oxidase. It is also predicted to play role in the synthesis of hormones such as melatonin and testosterone.

As of now, four enzymes have been detected to be in charge of D-amino acid metabolism in mammals. How these are controlled is still unknown.

Publications pertaining to the association of epilepsy, schizophrenia, and bipolar disorders with enzymes in charge of D-amino acid synthesis and break down have increased in recent years. From this point of view, serine racemase and D-amino oxidase can be used to develop new potential drugs regarding the treatment of similar NMDA receptor associated diseases.

The first data demonstrating the use of D-amino acids in saliva in organs outside of the human brain was obtained by Y. Nagata and his team at the University of Nihon, Tokyo. A team led by Kenji Hamase of the Kyushu University discovered high levels of D-alanine storage in the beta cells of the rat pancreas. Kuchel, who discovered the enzymes converting the L-amino acids in to D forms in duck-billed Platypus poison, also found similar enzymes in the hearts of mice and humans. According to Kuchel, the physiological roles of those in humans remain to be unknown.

As a result, the common feature of toxins and antimicrobial peptides that are produced and secreted by animals is to contain D-amino acid. These peptides can be the source of a potential drug in the treatment of diseases such as cystic fibrosis, schizophrenia, and macular degeneration of the eye.

These prove that, especially in biology, exceptions are common; life is enriched via examples of extraordinary lives, processes, and mechanisms in unexpected places by unpredictable molecules or interesting reactions that can’t be predicted. Such discoveries help deepen our wonder at the intricacy and wisdom of creation.

Why is this surface area so large? What could the wisdom behind it be? Tiny endoplasmic canals play a role in inner cell transportation and distribution of matter. ER is the organized industry district in the cell. Most of the factories of molecules produced by chemical reactions are found here. ER is the production spot in the cells of proteins and hormones. Consequently, a broad surface area is very necessary and important.

Different degrees (pH) of acid are necessary for each reaction. However, because the acid necessary for one reaction can negatively affect the other reactions, thousands of opposite, intricate and different reactions take place. For this reason, membrane surface areas need to be wide. Sometimes hundreds of protein molecules are produced in just a second in a cell. The rapid and flawless lining up side-by-side of tens, hundreds or thousands of amino acids can only be achieved with a knowledge and power that surpasses these very small structures.

Wrapping the inside of the cell like a web and forming a buffer against mechanical effects, ER is responsible for establishing the flexibility and soundness of the cell. In muscle cells, ER takes the name Sarcoplasmic Reticulum (SR), which has a very important duty in the contraction of muscles. The size of the surface area of SR in the muscles of the structural frame is proportionate to the speed of muscle contraction. Consequently, there is more SR in muscle cells where there is rapid contraction. SR also serves as a calcium depot in muscle cells. Normally calcium is a deadly poison for the cell, and for this reason it is kept out of the cell. The concentration of calcium outside the cell is 10,000 times more than it is inside the cell. However, SR stores calcium in the cell in its own body. Thus, it both prevents the cell from being harmed and it provides the necessary calcium for contraction.

ER has the duty of eliminating the poison in the liver cells from the body by means of gall. For example, jaundice-causing bilirubin is a deadly poison for the brain especially in newborn babies. If jaundice is not treated, motor loss (paralysis) and intelligence loss can result from brain damage. Bilirubin and glucuronic acid combine by means of some enzymes on the surface of ER in the liver and are thrown into the gall bladder. In this way ER plays an important role in making foreign matter harmless and in reducing the side affects of medications to a minimum. Babies’ sensitivity to some medications during the first three months of life is due to ER’s not yet being developed enough to eliminate their harmful effects.

If it is taken into consideration that all of these mechanisms exist in human, animal and plant cells, it can be clearly seen that a broad and complex structure in such a small volume and its many functions can only have been placed there by the All-Powerful whose knowledge, wisdom, artistry, will and power permeate every moment and every spot.

Celaloglu is a freelance writer from Turkey with a degree in biology.

A man is willing to die (why?), his family seems to have no objections (how come?), there is an institution assisting this family (how come?), it is being recorded and broadcast (what?!).

The controversial documentary stirred up a reaction in some religious circles and pro-life charities, as viewers discussed the ethics of broadcasting euthanasia in the days following this program. But what is so chilly about this video is not whether a network should broadcast it, but a man’s willingness to end his own life. If life had any meaning for this person, he would not be willing to cause his own death. If he meant anything to his family, they would never allow him to do it. This story is so desperate, so heartbreaking, that it leaves us without words.

Mary Lahaj of Boston shares with us a story in this issue that would counterbalance the hopelessness and dispel the dark clouds the above-mentioned documentary caused. “At God’s Door” is the story of a woman who was able to stand up on her own feet after a traumatic youth. Hers is a source of inspiration for many of us who have failed, or feel on the edge of a cliff at times, to rise up in belief for a new life.

Professor Anwar Alam from India reviews a book on a global movement of education and dialogue: The Gulen Movement, Civic Service Without Borders is one of a handful of must-read books that authoritatively deals with this social phenomenon—called the Hizmet movement—affiliated with successful schools, dialogue activities, and relief organizations around the world.

An interview with Paul Davies lays down some of the “Great Questions of Existence” and shares with us how science can contribute to our making sense of them.

The Lead Article expounds on the rights of God and human rights, and how they are related. “Life” is one such right, and the Giver of Life certainly has something to say about this.

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.