Rabu, 21 September 2011

Top 10 Common Medical Myths

At the List Universe we love to dispel myths – so here we are, yet again, presenting another list of common myths that need to be debunked and forgotten once and for all. This time we look at medical myths – of which there are thousands. This is a selection of the ten most common, but do feel free to add your own to the comments.
Sugar Hyperactivity
The Myth: Sugar makes kids hyperactive
Dr. Vreeman and Dr. Carroll, both pediatricians at the Riley Hospital for Children recently said: “in at least 12 double-blinded, randomized, controlled trials, scientists have examined how children react to diets containing different levels of sugar. None of these studies, not even studies looking specifically at children with attention deficit-hyperactivity disorder, could detect any differences in behavior between the children who had sugar and those who did not.” This includes artificial and natural sources of sugar. Interestingly, in the study, parents who were told their children had been given sugar when they hadn’t, noted that the child was more hyperactive. So it seems it is all in the parent’s mind.

Body Heat
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The Myth: You lose most of your body heat through your head
A military study many years ago tested the loss of temperature in soldiers when exposed to very cold temperatures. They found rapid heat loss in the head – and so the idea that we lose heat through our heads was born. But what they didn’t tell you was that the soldiers were fully clothed except for their heads. This obviously skews the statistics considerably. The fact is, completely naked, you lose approximately 10% of your body heat through the head – the other 90% is lost via the other parts of your body.

Water Consumption
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The Myth: You should drink at least eight glasses of water a day
The origins of this myth is most likely the fact that a 1945 government agency said that the human body needed around 8 glasses of fluid a day. This included the fluid from all of the foods we eat and drinks like tea and coffee. Somehow over time “fluid” turned to “water” and the modern water myth arose. This also lead to silly slogans like “if you are thirsty it is too late” – a concept that would seem to have been invented by water bottlers who have something to gain from excess water consumption in the population in general. So, in reality, if you are thirsty, drink some water. If you are not, don’t.
Gummed Up
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The Myth: Chewing gum takes seven years to pass through your system
I am sure we have all been told at least once in our life by a concerned adult, not to swallow gum as it will take seven years to leave our bodies. This is right up there with the whole “fruit seed growing a tree in your stomach” silliness, but while most adults realize the tree story is a myth, they don’t realize that the gum one is too. It is true that gum is not digestible in the human body, but it simply passes whole through your system. It doesn’t stick to your insides, it just continues along with any food you have eaten and pops out the other end. This myth may have partly arisen from the fact that swallowing gum was once viewed as lower class and ignorant.
Arthritic Knuckles
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The Myth: Cracking your knuckles will cause arthritis in later life
The cracking sound in the knuckles is caused by the bones moving apart and forming a gas bubble – the sound is the bubble bursting. It is quite common to hear someone warning a knuckle-cracker that they will get arthritis, but the worst that can happen to a compulsive-cracker is that their finger joints may weaken over time. Arthritis is caused by a variety of things (such as crystal formations in the case of gout) – but knuckle cracking isn’t one of them.

Baby teeth
The Myth: Teething causes a fever
Scientific studies have been done in the area of teething which show no correlation at all between fever and teething. If your baby is suffering from a new tooth and they also have a fever, it is advisable to check for other causes of the fever. The same is true of diarrhea which is also often blamed on teething in infants. It is always better to be safe than sorry when dealing with the health of children.
Cancer Treatment
The Myth: Cancer treatment is painful and pointless – furthermore, it is incurable
While this may have been almost true thirty years ago, medical advances have meant that modern cancer treatments are far more effective and cause less suffering for the patient. A few decades ago, 90% of children with leukemia died; today 80% survive. Many people think cancer is incurable as there isn’t a “one drug fixes all” cure, but there are many people who are completely cured of cancer. Various drugs exist to treat different types of cancer, and many of them are extremely effective and well worth trying if you do get the disease.
Back Pain
The Myth: Back pain should be treated with bed rest
The opposite is actually true in this case. Bed rest can prevent the lower back from fully recovering – or at the very least, delay the recovery significantly. Patients who continue to engage in ordinary activities recover faster and usually have fewer problems with recurring pain and other back troubles. Interestingly, many studies have shown that this is not just true of back problems, but also many other medical problems. Thirty-nine independent studies found bed rest to be more harmful than good in a broad range of illnesses.
Turkey Sleep
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The Myth: Eating turkey makes you sleepy because it contains tryptophan
This is one of the most common myths on this list – and it pops up every year around Thanksgiving. But actually, chicken and ground beef contain almost identical quantities of tryptophan as turkey does. Other foods such as cheese and pork contain significantly more of the chemical than turkey. So why do people think turkey makes them sleepy? It is most likely due to turkey appearing at very large meals often eaten during the day rather than the evening. The heavy meal slows blood flow which can cause drowsiness, and the timing can have a huge psychological impact: in other words, you are imagining it.
Midnight Snacks
The Myth: Eating at night makes you fat
Secret snackers rejoice! This is a complete myth. It doesn’t matter what time of day you eat, as long as you eat only the total calories that you burn each day, you will not gain weight. If you eat fewer calories than you burn, you will lose weight, and if you eat more calories, you will gain. It is as simple as that. Having said that, the routine of three meals a day at the same time each day can have other benefits in life (routine is good and it helps humans work more effectively), but snacks at night are no worse than snacks in the morning or afternoon.
Weight Gain
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The Myth: It is harder to lose weight than to gain weight
Actually – once you get your head around a new eating pattern, math and science are working in your favor. It is mathematically easier to lose than to gain. For example, if you eat 3,500 calories more than you burn, you will gain 0.3 pounds (0.14 kg), but if you burn 3,500 calories more than you eat, you will lose 1 pound (0.45 kg). Also, if you want to lose weight, you can expose yourself to significant changes in temperature which speeds up your metabolism. Finally, the above information is based on a pure fat diet – variations to the math occur when you introduce other types of food.

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Rabu, 27 Juli 2011

Top 10 Common Myths About Cannabis

Cannabis is probably the world’s most popular casual use drug that is illegal in most nations. It has become so widespread that many people wouldn’t think twice about asking to light up at a friend’s or to smoke in public places. It is an ancient drug that has been used throughout history for medical, magical, and pleasurable purposes. Thanks to the scare-tactics of propaganda in the 1960s and 1970s, there are many myths surrounding the drug – this list intends to put things straight once and for all.
Fat Storage
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Myth: Cannabis’ active ingredient THC gets stored in body fat and its effects can last days or even weeks
Fact: It is true that cannabis (like many other drugs) enters the body’s fat stores, and it is for this reason that it can be detected long after use, but that is the only part of this myth which is true. The fact is, the psychoactive aspects of the stored cannabis are used up quickly and while the residue of the drug remains, it no longer has any effect on the person. Furthermore, the presence of THC in body fat is not harmful to the fat, the brain, or any other part of the body.

Memory Loss
Myth: Cannabis use causes memory loss and a general reduction in logic and intelligence
Fact: This is another myth which has elements of truth to it – no doubt the reason it is believed by so many. Laboratory tests have shown that cannabis diminishes the short term memory – but only when a person is intoxicated with it. A person who has taken cannabis will be able to remember things learned before they took it but may have trouble learning new information during intoxication. There is no scientific evidence whatsoever to suggest that this can become a long-term or permanent problem when sober.

Scientific Proof
Myth: Cannabis has been scientifically proven to be harmful
Fact: Let us start with a quote: “the smoking of cannabis, even long term, is not harmful to health.” This quote comes from the peer-reviewed British medical journal The Lancet (founded in 1823). There is certainly no scientific consensus on cannabis use, and certainly no scientific proof that casual use is dangerous to health.
Loss of Motivation
Myth: Cannabis use causes apathy and a lack of motivation
Fact: In fact, studies done on test subjects in which they were given a high dose of cannabis regularly over a period of days or weeks found that there was no loss in motivation or ability to perform. Of course, abuse of any intoxicating substance over long periods will reduce a person’s ability to function normally, but cannabis is no better or worse. Furthermore, studies indicate that cannabis users tend to have higher paid jobs than non-users.
Crime Statistics
Myth: Cannabis causes crime
Fact: Some people believe that cannabis use leads to violence and aggression, and that this, in turn, leads to crime. But the facts just don’t stack up. Serious research into this area has found that cannabis users are often less likely to commit crimes because of its effect in reducing aggression. Having said that, because of the number of nations that have outlawed cannabis, most users in the world are technically classified as criminals merely for possessing the drug.

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Myth: Cannabis kills brain cells
Fact: Cannabis does not cause any profound changes in a person’s mental ability. It is true that after taking the drug some people can experience panic, paranoia, and fright, these effects pass and certainly don’t become permanent. It is possible for a person to consume so much of the drug that they suffer from toxic psychosis, but again this is not unique to cannabis and is very rare.
Gateway to Other Drugs
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Myth: Cannabis is a gateway drug – in other words, it leads to abuse of more potent drugs
Fact: For most people, cannabis is a terminus drug, not a gateway drug. Users of high strength drugs such as heroin or LSD are also statistically more likely to have used cannabis in the past, but this is just toying with statistics; when comparing the number of cannabis users with hard-drug users, the numbers are extremely small – suggesting that there is no link at all.
Modern Potency
Myth: Cannabis is more potent now than in the past
Fact: The reason that this myth has come about is that samples taken by drug enforcement agencies are used to test for potency but they are a tiny sample of the cannabis on the market. The vast majority of cannabis taken today is the same potency as it has been for decades. In fact, even if the potency were greatly higher, it would make little difference to the user as cannabis of varying potency produces very similar effects. Furthermore, there is statistical data on cannabis potency dating back to the 1980s which is more reliable than present methods of detection, and that shows little or no increase.
Lung Damage
Myth: Cannabis is more damaging to the lungs than cigarettes
Fact: First of all, people who smoke cannabis but not cigarettes tend to smoke far less frequently – thereby limiting their exposure to the dangers in the smoke. Furthermore, smokers of cannabis are not inhaling the many additives that go into commercial cigarettes to make them burn down faster or to stay alight. There has even been some evidence that marijuana smoke does not have the same effect on the bronchial tubes as cigarette smoke, so even heavy use may not lead to emphysema.
Cannabis and Addiction
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Myth: Cannabis is highly addictive
Fact: Less than one percent of Americans smoke cannabis more than once per day. Of the heavy users, a tiny minority develop what appears to be a dependence and rely on the assistance of drug rehabilitation services to stop smoking but there is nothing in cannabis which causes physical dependence and the most likely explanation for those who need assistance is that they are having difficulty breaking the habit – not the “addiction”.
This list was inspired by the excellent work of the Drug Policy Alliance Network.

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Rabu, 22 Juni 2011

10 Debunked Scientific Beliefs Of The Past

Science fills us all with great wonder and it has done so for generations, but there have been an incredible number of “scientific discoveries” which were later found to be completely false. This list looks at ten of the more fascinating cases of scientific falsehoods from history.
Rain Follows the Plow
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“Rain Follows the Plow” is the name given to a climatology concept which is now completely debunked. The theory said that human settlement caused a permanent increase in rainfall – thus enabling man to move to areas previously considered arid. It is this 19th century theory that brought about the settlement of the Great Plains (previously known as the Great American Desert), and parts of South Australia. The theory was eventually refuted by climatologists, and in the settled areas of South Australia, drought brought an end to the attempted settlements.

World Ice Theory
Hanns Hoerbiger
This strange theory has a relatively normal name, but rest assured, the concept is far from it. Hans Hörbiger (pictured above), an Austrian engineer and inventor received a vision in 1894 which told him that ice was the substance of all basic substances and had created the ice moons, ice planets, and a “global ether”. He said “I knew that Newton had been wrong and that the sun’s gravitational pull ceases to exist at three times the distance of Neptune[.]” Unbelievably this theory got a great deal of support. One of the strongest supporters of the concept was Houston Stewart Chamberlain (British born posthumous son-in-law of composer Richard Wagner) who went on to become one of the leading theorists behind the development of the Nazi Party in Germany.

Bruegel Alchemist
Alchemy has its roots (in the Western world) in Ancient Egypt where it combined with metallurgy in a form of early science. The Egyptian alchemists discovered the formulas for making mortar, glass, and cosmetics. From Egypt it eventually spread to the rest of the Ancient world and led to modern alchemy in which men would try to turn metals into gold, to conjure up genies, and perform all manner of bizarre not-so-science-like activities. While it has contributed in some ways to modern science, the discipline of true science caused the death of alchemy which could not stand up to the rigorous testing of its pseudoscience.
California Island
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From the 16th century, European experts in geography were convinced that California was an island separate from the North American mainland. Maps of the time show a large island on the left of the land mass and California continued to appear this way even into the 18th century. There was at the time also a rumor that California was an earthly paradise like the Garden of Eden or Atlantis. A romance novel from 1510 describes it thus:
Know, that on the right hand of the Indies there is an island called California very close to the side of the Terrestrial Paradise; and it is peopled by black women, without any man among them, for they live in the manner of Amazons. — Las Sergas de Esplandián by Garci Rodríguez de Montalvo
The matter was finally put to rest indisputably on the 1774-1776 expeditions of Juan Bautista de Anza. Interestingly, it is likely that within 25 million years, Baja California and part of Southern California really will separate from North America due to tectonic plate movement.
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Geocentricity is the concept which states that the earth is the center of the Universe and that all other objects move around it. The view was universally embraced in Ancient Greece and very similar ideas were held in Ancient China. The idea was supported by the fact that the sun, stars, and planets appear to revolve around Earth, and the physical perception that the Earth is stable and not moving. This was combined with the belief that the earth was a sphere; belief in a flat earth was well gone by the 3rd century BC. The geocentric model was eventually displaced with the work of of Copernicus, Galileo, and Kepler in the 16th Century.

The Four Humors
The Four Humors
In classical antiquity right up to modern times, it was believed that the body contained four humors: blood, yellow bile, black bile, and phlegm. It was believed that the right balance of these four humors made a person healthy but an excess or decrease in any one of these would cause illness. Because of this belief, treatments of sickness would include bloodletting, purges, and emetics. Occasionally a mixture of herbs would be used to restore the balance. The humors were also applied to foods – for example wine was choleric (yellow bile). This classification still exists today to some extent, as we refer to some foods as “hot” and others as “dry”. The concept of humors was not replaced until 1858 when Rudolf Virchow published theories of cellular pathology.
Vitalism states that the functions of living things are controlled by a “vital force” and not biophysical means. Vitalism has a long history in medical philosophies – and it has ties to the four humors. It is sometimes referred to as a “life spark” and even as the soul. In the Eastern traditions it is essentially the same thing as “qi” or “chi”, which is heavily tied in to oriental medicinal methods. The concept is (as can be expected) completely rejected by most mainstream scientists. In 1967, Francis Crick, the co-discoverer of the structure of DNA, stated “And so to those of you who may be vitalists I would make this prophecy: what everyone believed yesterday, and you believe today, only cranks will believe tomorrow.”
Maternal Impression
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Maternal Impression is an old belief that a mother’s thoughts while pregnant can impart special characteristics on the child in her womb. For many years this idea was used to explain congenital disorders and birth defects. Maternal Impression was used to explain the disorder suffered by the Elephant Man: it was suggested that his mother was frightened by an elephant while she was pregnant with him – thereby imprinting the memory of an elephant on her child. Depression was also explained in this manner. If a mother had moments of strong sadness during pregnancy, it was believed that her child would ultimately suffer from depression in later life. Genetic theory caused the almost complete eradication of this belief in the 20th century.
The theory of phlogiston dates to 1667 when Johann Joachim Becher (a German physicist) suggested that there was a fifth element (phlogiston) to go with the four classical elements (Earth, Water, Air, Fire) which was contained within objects that could burn. It was believed that when an object burned, it released its phlogiston (an element without taste, mass, odor or color) and left behind a powdery substance called calx (what we now know to be oxide). Objects that burned in air were considered to be rich in phlogiston and the fact that a fire burned out when oxygen was removed was seen as proof that oxygen could only absorb a limited amount of the substance. This theory also led to the idea that the human need to breathe had a sole function which was to remove phlogiston from the body. The entire concept was superseded by Antoine-Laurent Lavoisier’s discovery that combustion could only occur with the help of a gas such as oxygen.
Spontaneous Generation
Before microscopes and theories of cells and germs, man had other ideas about the creation of living things. He bizarrely believed that life arose from inanimate matter (for example, maggots come spontaneously from rotting meat). Proponents of this view (virtually everyone) used the Bible as a source of evidence, due to the fact that God made man from dust. However, the view did exist before Christianity and Aristotle said, in no uncertain terms, that some animals grow spontaneously and not from other animals of their kind. Earlier believers had to come up with some pretty strange ideas to make their theory work: Anaximander (a Greek philosopher who taught Pythagoras) believed that at some point in man’s history, humans had been born from the soil spontaneously in adult form, otherwise they could never have survived. Before we laugh too hard at the ancients, we should note that many Scientists right up to the 19th century believed this, and some even wrote recipe books for making animals. One such recipe (to make a scorpion) calls for basil, placed between two bricks and left in sunlight. The theory was not finally put to rest until 1859, when Louis Pasteur proved it wrong once and for all.

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Senin, 20 Juni 2011

Top 10 Old Wives’ Tales Debunked

Almost all of us have, at some time, been chided by a parent or grandparent who has been mislead by an old wives’ tale. Their intentions are always good, but unfortunately they are misguided. There are thousands of old wives’ tales – ranging from the seemingly logical to the outright bizarre.
This is a list of ten of the most common old wives’ tales which are, in fact, bunkum! Feel free to use the comments to tell us about some of the more unusual tales you have come across in your life.
Feed a Fever Starve a Cold
In fact, both colds and fevers cause dehydration – so liquids are essential when suffering from either. In addition, missing out on food when you are sick is never a good idea as food provides the body with the sustenance it needs to get healthy. So, you should feed a fever and feed a cold. This, of course, does not mean to overeat – it means to eat healthy balanced meals.

Eating Before Swimming
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There is an old wives’ tale that says that if you eat within an hour of swimming you will get cramp. The Red Cross says that eating directly prior to swimming does not increase risk of cramp at all. They do, however, recommend at least waiting for digestion to begin if you have eaten a particularly fatty meal. They also recommend that you not eat gum or food while you are swimming.

Chocolate Causes Acne
There is actually not an iota of evidence to support this tale – no food type (not just chocolate) can cause acne or bad skin. Needless to say, eating too much chocolate or sugary food is unhealthy for the body, but it will not cause skin problems. Acne is actually caused by changes in the lower layers of the skin surrounding hair follicles.
Carrots Improve your Vision
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It is possible that this tale came about due to allied propaganda during the second world war when rumors were spread that the British airmen had excellent night vision due to eating carrots. The myth was spread to stop the Germans from discovering that the British were using Radar. While carrots contain vitamin A which is good for healthy eyes, eating lots of them will do nothing to improve your vision.
Catching a Cold
There are a huge number of myths about how to catch a cold, but in fact there is only one way to catch a cold virus – by direct contact with the virus itself. You can stand outside on a cold night with wet hair and your chances of getting a cold do not increase at all. The reason that colds seem to spread more in Winter is not from the cold itself, but the fact that people tend to live more often indoors and this increases your chances of coming in to contact with a sufferer. It is also worth mentioning that if you get a cold in your nose, you can not stop it from spreading to your chest if the virus is programmed to attack you there. Most cold medicines are completely pointless and do nothing to help except alleviate the pain through the inclusion of painkillers.

TV and Eyesight
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My parents constantly told me off for sitting too close to the television when I was a kid – I was told that my eyesight would deteriorate from doing so. The same was also said of reading in dim light. In fact, neither of these things do any damage to the eyes. It should be noted, however, that spending too much time in front of the TV is not good for children (regardless of how close they sit) as research has shown that children who spend 10 hours or more in front of the television each week are more likely to become overweight, aggressive, and slower in school.
Masturbation Causes Blindness
The tale states that masturbation will cause blindness (in France it is said it will cause deafness). This is not true (at least not completely) and the idea has probably been spread in order to prevent children from masturbating for religious reasons. Curiously, sperm contains quite a lot of zinc, and a serious zinc deficiency can cause a decline in vision. However, it is nearly impossible to cause a zinc deficiency through masturbating.
Knuckles and Arthritis
While it is true that constant knuckle cracking can reduce the strength of your grip and cause swelling, it does not lead to arthritis. There are many causes of arthritis (such as trauma or infection of a joint, or old age), but knuckle cracking is not one of them.
Spicy Food and Ulcers
Spicy Chicken Masala Curry
If a person suffers from an ulcer, spicy food can often aggravate it; however, ulcers are not caused by spicy food at all – if they were, ulcers would be pandemic in many eastern nations. An ulcer is usually caused by overuse of medications like aspirin and anti-inflammatories.
Toads and Warts
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It is almost certain that this strange old wives’ tale has come about because of the appearance of wart-like growths on many toads. In fact, these growths are not human compatible at all. Warts are caused by viruses and they are almost always exclusive to a particular genus of creature. Human’s cannot catch warts from other animals, and animals can not catch human warts. The most common human wart virus is called the human papillomavirus.

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Rabu, 11 Mei 2011

Another 10 Common Misconceptions

Lists about misconceptions and common errors are always popular. This is our second list of common misconceptions covering a variety of topics. Some misconceptions have come about through mistranslations, and others through Chinese-whispers like scenarios. This is another list of 10 common misconceptions.
10. Taste Buds Tot2006
Different tastes can be detected on all parts of the tongue, contrary to the popular belief that specific tastes correspond to specific sites on the tongue. The original “tongue map” was based on a mistranslation by a Harvard psychologist of a German paper that was written in 1901. Sensitivity to all tastes occurs across the whole tongue and indeed in other regions of the mouth where there are taste buds (epiglottis, soft palate).

9. Black Hole Hokum
The gravity of a black hole is slightly less than the gravity of the star that caused it. Black holes are not “cosmic vacuum cleaners”; objects can settle into stable orbits around them just as they would around any other mass in space, including stars.

8. Paul Revere’s Ride Ride-Of-Paul-Revere
Paul Revere was not the only American colonist who rode to warn the Minute Men of the British before the battle of Lexington and Concord of the American Revolutionary War. The story of Paul Revere is largely based on the poem “Paul Revere’s Ride”, written by Henry Wadsworth Longfellow in 1860.
7. CCTV Cameras Deter Crime
There is actually little evidence that CCTV security cameras deter crime; the most measurable effect of CCTV is not on crime prevention, but on detection and prosecution.
6. 72 Black Eyed Virgins
Muslim martyrs will not go to heaven and marry 72 black eyed virgins. This idea stems from a mistranslation: the Quran says martyrs going to heaven will get “hur,” and the word was taken by early commentators to mean “virgins.” But in Aramaic, hur meant “white” and was commonly used to mean “white grapes,” which the Quran compares to crystal and pearls, and contemporary accounts have paradise abounding with fruit, especially white grapes.

5. Mary Magdalen was a Prostitute Ivanov3A
The Bible makes no mention at all of Mary Magdalene being a prostitute. Before her seeing the risen Jesus, the only other mention besides the listing of her name is the mentioning in Luke 8:2 that she had been possessed by seven demons.
4. Worm Clones
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Many people believe that if you cut a worm in two, it will continue to live as two worms. In fact, a worm can survive being cut in half, but only one half can survive the operation; the other half dies.
3. Lemming Suicide
There is a widespread myth that lemmings throw themselves off cliffs in order to commit suicide in a bizarre natural method of keeping the populace under control. This is entirely untrue. The myth came about because of the Disney film White Wilderness, in which lemmings were filmed throwing themselves off cliffs. What really happened is the film crew used brooms to push the lemmings off the cliff.
2. Memory of a Goldfish
Goldfish are often thought of as having very short memories – usually up to a few seconds at the most. In fact, goldfish have been trained to navigate mazes, and after a few months it can recognize its owner.
1. Hair and Fingernails
Contrary to popular belief, hair and fingernails do not continue to grow after a person dies. The most likely cause of this myth is shrinkage in the skin after death which gives the false appearance of growth of the nails.

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