History

• The belief that gunpowder, even though it was a Chinese invention, was first used for war by the Europeans is a misconception. The Chinese used flame throwers and gunpowder arrows for military purposes from the 900s onward.
  
  


• 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 (see Paul Revere's Ride).
  
  


• Christopher Columbus's efforts to obtain support for his voyages were not hampered by a European belief in a flat Earth. In fact, sailors and navigators of the time knew that the Earth was spherical, but (correctly) disagreed with Columbus' estimates of the distance to the Indies (see Flat Earth). If the Americas did not exist, and Columbus had continued to the Indies (even putting aside the threat of mutiny he was under) he would not have survived long enough to reach them at the rate he was going.
  
  


• Abraham Lincoln's Emancipation Proclamation did not immediately free all American slaves because it took winning the civil war to bring Confederate slaves under his authority and it took the thirteenth Amendment to the United States Constitution to free slaves in the few Union slave states. Some slaves were immediately freed by the Emancipation Proclamation; but most slaves were freed as Confederate territory came under Union control.

• Napoleon Bonaparte (pictured) was not especially short. After his death in 1821, the French emperor's height was recorded as 5 feet 2 inches in French feet. This corresponds to 5 feet 6.5 inches in Imperial (British) feet, or 1.686 metres, making him slightly taller than an average Frenchman of the 19th century. The metric system was introduced during his lifetime, so it was natural that he would be measured in feet and inches for much of his life. A French inch was 2.71 centimetres, an Imperial inch is 2.54 centimetres. In addition to this miscalculation, his nickname, "le petit caporal", adds to the confusion, as non-francophones mistakenly take petit literally as meaning "small"; in fact, it is an affectionate term reflecting on his camaraderie with ordinary soldiers. He also surrounded himself with soldiers, his elite guard, who were always six feet tall or more.
  
  


• During World War II, King Christian X of Denmark did not thwart Nazi attempts to identify Jews by wearing a yellow star himself. Jews in Denmark were never forced to wear the Star of David. The Danish government did help most Jews flee the country before the end of the war.
  
  


• Italian dictator Benito Mussolini did not make the trains run on time. Much of the repair work had been performed before Mussolini and the Fascists came to power in 1922. Accounts from the era also suggest that the Italian railways' legendary adherence to timetables was more myth than reality.
  
  


• It is believed that the phrase "Qu'ils mangent de la brioche." ("Let them eat cake.") was not said by Marie Antoinette, but by another noble (a princess in another country, at another time). An argument to support this theory is that the brioche had not been invented, yet, by the time of the French Revolution. Also, Jean-Jacques Rousseau recounts the anecdote in the 6th book of his 'Confessions' three years before Marie Antoinette joined the court at Versaille in 1770.
  
  


• The German crowd witnessing John F. Kennedy's speech did not, as commonly believed only in the United States, mistake Ich bin ein Berliner to mean "I am a jelly doughnut". Although that was an interpretation of the phrase, the people of Berlin understood his intent.

Food origins

• Spaghetti bolognese did not originate in Italy. The actual name in Italian is spaghetti con ragù (spaghetti with ragù).


• French fries probably originated in Belgium. The name comes from the cooking term "to French" which means to cut food into strips, hence they are "frenched and fried".


• French dressing neither originated, nor has been popular, in France.


• Danish pastries do not come from Denmark but Austria. In Denmark they are known as "wienerbrød" ("Vienna bread").

Astronomy

• While in a low orbit, a viewer can see the Great Wall of China (pictured here in a satellite image) from space, but it is not unique in that regard. From a low orbit of the earth, many artificial objects are visible on the earth, not just the Great Wall of China: highways, ships in the sea, dams, railroads, cities, fields of crops, airports, and even some individual buildings. As to the claim that it is the only man-made object visible from the moon, Apollo astronauts reported that they could not see any man-made object from the moon, not even the Great Wall.
  
  


• The phrase "dark side of the Moon" is thought to refer to the a side of the moon that is always dark. In fact, it refers to the far side of the moon where radio transmissions from Earth are blocked by the intervening mass of the Moon (making it "dark" to line-of-sight communications). Since the Moon is locked in a synchronous orbit, it always keeps the same side toward the Earth, and therefore the far side is never visible from Earth. Once per synodic month, the near side of the Moon is indeed largely illuminated by the Sun, and the far side is literally "dark". At this time, we are able to see most of the area of the near side, resulting in a full moon.
  
  


• 
  The gravity of a black hole is slightly weaker than, not stronger than, the gravity of the star which formed it (at distances greater than the star's radius). Isaac Newton's laws of gravitation state that, for an object with a spherically symmetric distribution of mass, two things affect how much gravitational force is felt by an observer: the mass of the object and the distance between the observer and the object's centre. A black hole has slightly less mass than the star which formed it, because when a star becomes a supernova, some of the star's mass is converted into energy according to Einstein's equation E = mc², and a great deal of the star's mass is returned to the interstellar medium. Only when a distance of (slightly less than) the star's original radius is passed does gravity become greater. The event horizon is usually much smaller than the original star's radius. As such, black holes are not similar to "cosmic vacuum cleaners". Objects can settle into stable orbits around them just as they would around any other mass in space, including stars.
  
  


• When a meteor lands on Earth (after which it is termed a meteorite), it is not usually hot. Small meteorites are not hot when they fall to Earth — in fact, many are found with frost on them. A meteorite has been in the near–absolute zero temperature of space for billions of years, so the interior of it is very cold. A meteor's great speed is enough to melt its outside layer, but any molten material will be quickly blown off (ablated), and the interior of the meteor does not have time to heat up because rocks are poor conductors of heat. Also, atmospheric drag can slow small meteors to terminal velocity by the time they hit the ground, giving them time to cool down.
  
  


• The North Star, Polaris, is not the brightest star in the night sky, contrary to popular belief. This honour is held by Sirius, with an apparent magnitude of -1.47 (Polaris in comparison is 1.97, barely making the top-50 brightest stars list). Its importance lies in its proximity to the north celestial pole, meaning its location in the sky currently marks North.
  
  


• Seasons are not caused by being closer to the Sun in summer and farther in winter due to Earth's elliptical orbit. In fact, Earth's elliptical orbit approximates a circle to such an extent that temperature differences between summer and winter cannot be explained by differing distances. Instead, Earth exhibits seasons because of its axis tilt of 23 degrees. This causes, for example, New Zealand's Winter to coincide with the United Kingdom's Summer.
  
  


• The Lunar phases are not caused by the Earth's shadow. Instead, as the Moon orbits Earth, we see its illuminated half from differing angles in relation to the Sun.

Health

• People do not use only ten percent of their brains. This myth is thought by some to have emerged after the discovery of glial cells in the brain, or it could have been the result of some other misunderstood or misinterpreted legitimate scientific findings, or even been the result of speculation by self-help gurus.

• 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).

• Warts on human skin are caused by viruses that are unique to humans (Human papillomavirus), and not by proximity to, or contact with, toads.


• Koalas are not bears. They are not even placental mammals; they are marsupials.


• Some bats use echolocation to navigate whilst flying in darkness. Bats are not blind, however. Their eyes are small and poorly developed, but they are still capable of sight, particularly long-range; and in fact can be severely disoriented by excessive light.


• The claim that a duck's quack doesn't echo is false.


• Jellyfish and starfish are not fish. They are Cnidarians and Echinoderms respectively. Many scientists refer to them as "sea jellies" and "sea stars".


• Polar bears do not eat penguins. Polar bears only live in the Arctic, while penguins are not native to the northern hemisphere.


• The notion that goldfish have a memory of only three seconds is completely false. They have been trained to navigate mazes and can recognise their owners after an exposure of a few months.


• Lemmings do not engage in suicidal dives off cliffs when migrating. This misconception is due largely to the Disney film White Wilderness, which shot many of the "migration" scenes on a large turntable in a studio. Photographers later pushed the lemmings off a cliff using a broom.


• Mammal blood is bright red or scarlet when oxygenated and a darker red when not oxygenated (and never blue). However veins with deoxygenated blood do appear blue.

Physics

• The Coriolis effect does not determine the direction of rotation of water draining from sinks, bathtubs, or flushing toilets. The influence of the Coriolis effect on motions over such small distances and such short times is very small. Only motions on spatial scales of many miles (kilometers) and time scales of many minutes or hours, such as long-range missiles, weather systems, and ocean currents, are appreciably affected by the Coriolis force (for a small-scale system which can detect the Coriolis force, see Foucault pendulum). Most containers of water are not initially still; in order for the Coriolis effect to have a chance of prevailing, the rotation of the water relative to the container must be less than its rotation with the Earth. Even at the North or South Poles, where the effect is strongest, the movement of water in a tub would have to be slower than one rotation in 24 hours. Then, unless careful precautions are taken, the torque produced by flow over the geometry of the tub overwhelms the tiny Coriolis force. Most toilets inject water into the bowl at an angle, and will flush in the corresponding direction anywhere in the world: the resulting spin of the water in the bowl is fast enough to complete a rotation in seconds—tens of thousands of times too fast to be overcome by the Coriolis effect.
  
  


• It is not true that air takes the same time to travel above and below an aircraft's wing. This misconception is widespread among textbooks, reference books, and even appears in pilot training materials. If this were truly the case, there would be no lift generated by the wings and the plane wouldn't fly.

• Many textbooks state that electricity within wires flows at nearly (or even exactly) the speed of light, which can give the impression that electrons themselves move almost instantly through a circuit. The drift velocity of the charges (electrons) in a typical current-carrying wire is on the order of centimeters per hour (much slower than a snail) rather than hundreds of millions of meters per second (the speed of light). The random thermal motions of the electrons are much faster than the drift velocity, but still much slower than light, and with no tendency to occur in any particular direction. Where the electric current is visible, as in electrophoresis, the slow movement of brightly colored charge carriers can be seen directly. It is the electrical energy or signal which travels almost at the speed of light. Electrons, which have mass, can never travel at the speed of light (see Theory of relativity); moreover, not even the energy can travel at the absolute speed of light unless the metal conductors are immersed in vacuum. The electrical energy is transmitted through the electromagnetic field created by a voltage/current source. The field is propagated by photons, which move at the speed of light when in vacuum. Imagine a hose which is full of water and connected to a closed faucet. When the faucet is turned on, water begins coming out of the other end of the hose almost immediately; the speed of the pressure wave which starts the water in the hose moving is analogous to the speed of the electrical signal. But it takes much longer for the water entering the hose at the faucet to transit the entire hose; the water itself, analogous to the electrons in a current-carrying wire, moves along the hose much more slowly than does the information that the faucet has been opened. In alternating current, as used in wall outlets, the direction of current alternates rapidly (50 or 60 times per second), and in this case, the electrons stay in about the same place the entire time (on the filament inside a light bulb for instance), while vibrating back and forth over a very small distance.
  
  


• The blue color of lakes and oceans is not only a reflection of the blue sky. Water looks blue because water is blue; the water molecules do absorb some light, and they absorb red frequencies more than blue. The effect is small, so the blue color only becomes obvious when observing layers of water many meters (or more) thick. (This effect is noticeable to a lesser amount in white-painted swimming pools.) In salt water or mineral-laden fresh water, the color of dissolved minerals can also be seen. Sky-reflection does play a role, but only when the water surface is very calm, and only when the water is observed at a glancing angle less than approximately ten degrees.
  
  


• Astronauts in orbiting spacecraft are not experiencing true "zero gravity". In reality they are falling along with the spacecraft. Because gravity in a free-fall environment is not easily detected, conditions of free-fall will simulate a "zero-gravity" environment. NASA refers to these conditions as microgravity. Earth's gravitational effects are very strong at the low orbit altitudes used by the space shuttle (about 85% of gravity at Earth's surface), and of course there are also the effects of other planets and the Sun. Gravity falls off rapidly as one leaves the Earth's surface, but one can never completely escape the gravitational pull of the Earth (or any other mass in the universe) even at vast distances, though the effect may be negligible. A free-fall situation can be more properly called "simulated zero-gravity" since the free-falling bodies are actually under a strong gravitational pull. Simulated zero gravity can be experienced in any near-freefall situation, including extremely fast elevators (that only simulate reduced gravity) and skydiving (near-real simulation of zero gravity for a short time). Astronauts ride inside free-falling airplanes for training (see Vomit Comet).
  
  


• The Earth's North Magnetic Pole is not a north magnetic pole, but rather a south magnetic pole. Since a compass needle is a magnet whose "North" end has standard north polarity, and since magnetic poles are attracted to their opposites, the compass needle points to the magnetic south pole of the Earth's magnetic field. Therefore, the Arctic pole is a south-type pole, while the Antarctic pole is a north-type pole. (However, the poles have flipped in the past, with the last reversal being the Brunhes-Matuyama reversal of 780,000 years ago.) Earth also has a more complicated magnetic field than one might get from a simple dipole. The earth has a strong overall dipole on which is superposed on a weaker quadrupole, as well as higher-order magnetic moments. Not only have the magnetic poles moved to opposite geographic poles in the past, but they also drift around more or less randomly, presumably because of the movements of the molten nickel-iron alloy in the Earth's core.
  
  


• Due to Archimedes's principle, the melting of glaciers contributes far more to raising sea level than the melting of sea ice or floating icebergs. The predicted threat of rising sea levels due to global warming is mainly due to the detachment or melting of inland ice, such as that on Greenland and in Antarctica, the melting of glaciers, and the thermal expansion of seawater. Melting of sea ice in the Arctic makes only a tiny contribution, by lowering the global average salinity (and therefore the density) of seawater.
  
  


• The melting of Antarctic ice is not predicted to be the largest cause of rising sea levels in the near future. While complete melting of the Antarctic ice sheet would be the largest contribution to sea level change, according to IPCC predictions, the likelihood of this event is uncertain. Antarctica may even help offset rising sea level by accumulating more snow. At worst, the melting of Antarctic ice is predicted to be only the fourth-largest potential contribution to sea level rise by the year 2100 (−170 to +20mm), after thermal expansion of the world's oceans (+110 to +430mm), melting glaciers (+10 to +230mm), and melting Greenland ice (−20 to +90mm).

• A Crookes radiometer or "light-mill" (pictured) does not turn by radiation pressure. In fact, it turns in the opposite direction from what one would expect due to radiation pressure. The correct explanation is essentially that molecules of gas in the partial vacuum inside rebound from the vanes of the radiometer, transmitting a different force depending on the temperature of the gas (rebounding more forcefully from the black, hotter side of the vanes).
  
  


• Introductory science courses often teach that the period of a pendulum is independent of its amplitude, and students often mistakenly believe that is precisely true. It is only approximately true, and only for small amplitudes, for which a pendulum approximates simple harmonic motion.
  
  


• It is not true that a nozzle (or a person's thumb) on the end of a garden hose makes the water squirt farther because of the Bernoulli principle. The pressure at the end of a hose depends very much on the speed of the water which flows through miles of pipe. The faster the water moves through the pipe, the greater is the friction that cuts down pressure at the output end. (The friction in rusty pipes is even greater.) If the speed of the water is lessened, the friction also lessens and the pressure at the output is increased. Of course, if the water is shut off and does not flow there is no friction. This results in full pressure - but no water output. When the water is flowing, putting a finger over the end of the hose reduces the number of gallons per minute that flow through the pipe, so the water in the pipe moves more slowly. This results in less friction in the pipe and consequently more pressure left in the water when it arrives at the end of the hose - and it will squirt farther. This can be demonstrated by connecting a hose directly to a water tank with sufficient elevation (i.e., pressure). Any restriction on the end of the hose will reduce the flow of water, but the water will squirt the same distance.
  
  


• That all objects, irrespective of their masses, fall at the same rate in a vacumn (i.e. ignoring air resistance) is not entirely true. Rather, it depends on how you frame the experiment. The effect of gravity depends on the sum of masses (i.e. the object falling and the object it is falling towards), and not just on the mass of the heaviest object.

Evolution

• In biology the word evolution describes the changes that occur in populations of living organisms over time. Describing these changes does not address the origin of life: for that, see abiogenesis. The two are commonly and mistakenly conflated. Biological evolution likewise says nothing about cosmology, the Big Bang, or where the universe, galaxy, solar system, or Earth came from.
  
  


• The word "theory" in "the theory of evolution" does not imply doubt in mainstream science about the validity of this theory; the words "theory" and "hypothesis" are not the same in a scientific context (see Evolution as theory and fact). A scientific theory is a set of principles which, via logical deduction, explain the observations in nature. The same logical deductions can be made to predict observations before they are made. The theory describing how evolution occurs is a "theory" in the same sense as the theory of gravity, the theory of relativity, or indeed number theory.
  
  


• Evolution by natural selection is not an entirely random process; the random results of mutation are filtered by the non-random process of natural selection and other non-random mechanisms. On the other hand, some evolutionary changes result from genetic drift, and are entirely random.
  
  


• Evolution does not need to be directed (although some people believe it is). It is a process, like the fractal growth of a snowflake, where complex structures come from simple rules.


• Humans did not evolve from chimpanzees or any other modern ape; instead they share a common ancestor (possibly Sahelanthropus tchadensis) that existed around 7 million years ago in the late Miocene epoch.However, the genuses Ardipithecus and Orrorin are alternative candidates for this common ancestor.
  
  


• The process of evolution is not necessarily slow. Millions of years are not required to see evolution, or even to see speciation in action. Indeed, it has been observed multiple times under both controlled laboratory conditions and in nature.
  
  


• Evolution does not happen within a single organism: a chimpanzee cannot be born a chimpanzee and turn into a different species within its lifetime. Evolution deals with changes to the gene pool of a population, which accumulate only over generations. Similarly, organisms cannot pass on acquired traits to their offspring; a bodybuilder's children are not born with more muscles (but see epigenetics).
  
  


• Evolution is not a progression from "lower" to "higher", and evolution does not require an increase in complexity (see Evolution of complexity). A population can evolve to become simpler, and have a smaller genome — often called "devolution", but that is a misnomer.
  
  


• The theory of evolution does posit "transitional forms"... but not "endpoint forms". That is, every animal, plant, fossil that exists, is an example of a transitional form. Evolution is an eternal and continuous process.
  
  


• The claim that "almost all mutations are harmful" is false. In fact, most mutations have no noticeable effect. One study gives the average number of mutations that arise in a human conception to be around 128, with an average number of harmful mutations per conception of 1.3.
  
  


• The claim that individuals with a different number of chromosomes can never produce viable offspring is false - Przewalski's Horse, for example, can produce viable offspring with the common horse, despite a different number of chromosomes.
  
  


• The claim that evolution is not scientific since it cannot be falsified is not true. Any number of discoveries could potentially falsify evolution - for example the discovery of a contemporary mammal fossil in ancient rock strata.
  
  


• The claim that evolution makes no meaningful predictions is not true - for example the discovery of the relationship between chromosome 2 and chimpanzee chromosomes at the end of the completion of the human and chimp genome projects was predicted, and makes no sense except as evidence of a common ancestor.

Religion

• Nowhere in the Bible is the fruit eaten by Adam and Eve in the Garden of Eden referred to as an apple. The fruit is called the "Fruit of the Knowledge of Good and Evil" and not identified as a known species. In middle English, however, apple was a generic term for all fruit, other than berries but including nuts, as late as the 17th century. Since Adam and Eve use fig leaves to cover themselves, the original author of Genesis was probably referring to a fig.
  
  


• The Ten Commandments are not consistent from one religion to another, or even among Christians (although they are the same Ten among these groups) except for the Samaritans, they are grouped differently (see this chart for example). In addition, besides the Ethical Decalogue repeated in Exodus 20:2–17 and Deuteronomy 5:6–21, there is a different set of ten commandments, the Ritual Decalogue, in Exodus.
  
  


• The term immaculate conception does not refer to Jesus's conception by the Virgin Mary (see Virgin Birth of Jesus), but rather to the Roman Catholic teaching that Mary herself was conceived without the stain of Original Sin. (See also Blessed Virgin Mary.)
  
  


• The number of Biblical Magi who visited Jesus is never specified, only that they carried three gifts. Additionally, they are never referred to as "kings". In addition, whilst they were said to have been informed of the birth of Jesus by the appearance of a new star, there is no textual evidence to suggest that they followed it.
  
  


• Nowhere in the Bible is Mary Magdalene ever referred to as a prostitute. Before her seeing of 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.
  
  


• The word "prodigal" in the parable of the Prodigal Son does not mean one who travels (or, alternatively, one who travels and then returns). "Prodigal" means "characterized by a profuse or wasteful expenditure". The Prodigal Son of the story wasted all of the money he obtained from his father and had to work as a lowly pig-tender until he finally recouped his losses and went back to his home.

Technology

• Thomas Crapper did not invent the flush toilet, Thomas Edison did not invent the light bulb, and Henry Ford did not invent the automobile or the internal combustion engine. In all three cases, their contributions were in the area of improving and popularizing the devices in question. For example, Ford introduced the assembly line, and used it to bring the cost of automobiles into reach of many more people, and Thomas Edison refined the internal gases and filaments, making a bulb last longer.


• ENIAC was not the first digital computer. Rather, it was the first general-purpose all-electronic computer. The Atanasoff-Berry Computer (ABC) and the Colossus computer were digital electronic computers but were not general-purpose, being designed for only particular applications. The Z3 was general-purpose but was partly electromechanical rather than electronic. Also, ENIAC did not use binary arithmetic, as the above three did (and as modern computers do); it used decimal.