35 Debunked Myths: Clearing Up Common Misconceptions – Part 1

420 did not originate from the Los Angeles police or penal code for marijuana use. In California, Police Code 420 means "juvenile disturbance", and California Penal Code section 420 prohibits the obstruction of access to public land. The use of "420" started in 1971 at San Rafael High School, where it indicated the time, 4:20 pm, when a group of students would go to smoke under the statue of Louis Pasteur.

2. Bulls are not enraged by the color red, used in capes by professional matadors. Cattle are dichromats, so red does not stand out as a bright color. It is not the color of the cape, but the perceived threat by the matador that incites it to charge.

3. The plate armor of European soldiers did not stop soldiers from moving around or necessitate a crane to get them into a saddle. They would as a matter of course fight on foot and could mount and dismount without help. In fact, soldiers equipped with plate armor were more mobile than those with mail armor (chain armor), as mail was heavier and required stiff padding beneath due to its pliable nature. It is true that armor used in tournaments in the late Middle Ages was significantly heavier than that used in warfare, which may have contributed to this misconception.

4. Flowering sunflowers point in a fixed direction (often east) all day long. However, in an earlier developmental stage, before the appearance of flower heads, the immature buds do track the sun (a phenomenon called heliotropism) and the fixed alignment of the mature flowers toward a certain direction is often the result.

5. The term "Immaculate Conception", was not coined to refer to the virgin birth of Jesus, nor does it reference a supposed belief in the virgin birth of Mary, his mother. Instead, it denotes a Roman Catholic belief that Mary was not in a state of original sin from the moment of her own conception.

The use of triangular corner flags in English football is not a privilege reserved for those teams that have won an FA Cup in the past, despite a wide belief to the contrary that inspired a scene in the film 'Twin Town'. The Football Association's rules are silent on the subject, and often the decision over what shape flag to use has been up to the individual club's groundskeepers.

7. Poinsettias are not highly toxic to humans or cats. While it is true that they are mildly irritating to the skin or stomach, and may sometimes cause diarrhea and vomiting if eaten, an American Journal of Emergency Medicine study of 22,793 cases reported to the American Association of Poison Control Centers showed no fatalities and few cases requiring medical treatment. According to the ASPCA, poinsettias may cause light to mid-range gastrointestinal discomfort in felines, with diarrhea and vomiting as the most severe consequences of ingestion.

8. Medieval Europeans did not believe Earth was flat; in fact, from the time of the ancient Greek philosophers Plato and Aristotle, belief in a spherical Earth remained almost universal among European intellectuals. As a result, Christopher Columbus's efforts to obtain support for his voyages were hampered not by belief in a flat Earth but by valid worries that the East Indies were farther than he realized. If the Americas had not existed, he would surely have run out of supplies before reaching Asia.

9. Meteorites are not necessarily hot when they reach the Earth's surface. In fact, some meteorites have allegedly been found with frost on them. As they enter the atmosphere, having been warmed only by the sun, meteors have a temperature below freezing. The intense heat produced during passage through the upper atmosphere at very high speed then melts a meteor's outside layer, but molten material is blown off and the interior does not have time to warm appreciably. Most meteorites fall through the relatively cool lower atmosphere for as long as several minutes at subsonic velocity before reaching the ground, giving plenty of time for their exterior to cool off again.

10. Sharks can suffer from cancer. The misconception that sharks do not get cancer was spread by the 1992 Avery Publishing book Sharks Don't Get Cancer by I. William Lane and used to sell extracts of shark cartilage as cancer prevention treatments. Reports of carcinomas in sharks exist, and current data do not allow any speculation about the incidence of tumors in sharks.

Golf did not originate as an acronym of "Gentlemen Only, Ladies Forbidden". The word's true origin is unknown, but it existed in the Middle Scots period.

12. Earthworms do not become two worms when cut in half. Only a limited number of earthworm species are capable of anterior regeneration. When such earthworms are bisected, only the front half of the worm (where the mouth is located) can feed and survive, while the other half dies. Some species of planarian flatworms, however, actually do become two new planarians when bisected or split down the middle.

13. The word "f*ck" did not originate in Christianized Anglo-Saxon England (7th century C.E.) as an acronym for "Fornication Under Consent of King"; nor did it originate as an acronym for "For Unlawful Carnal Knowledge", either as a sign posted above adulterers in the stocks, or as a criminal charge against members of the British Armed Forces; nor did it originate during the 15th-century Battle of Agincourt as a corruption of "pluck yew" (an idiom falsely attributed to the English for drawing a longbow). Modern English was not spoken until the 16th century, and words such as "fornication" and "consent" did not exist in any form in English until the influence of Anglo-Norman in the late 12th century. The earliest certain recorded use of "f*ck" in English comes from c. 1475, in the poem "Flen flyys", where it is spelled fuccant (conjugated as if a Latin verb meaning "they f*ck"). It is of Proto-Germanic origin, and is related to either Dutch fokken and German ficken or Norwegian fukka.

14. Evolution is not a progression from inferior to superior organisms, and it also does not necessarily result in an increase in complexity. A population can evolve to become simpler, having a smaller genome, but biological devolution is a misnomer.

15. Ostriches do not stick their heads in the sand to hide from enemies. This misconception was probably promulgated by Pliny the Elder (23–79 C.E.), who wrote that ostriches, "imagine, when they have thrust their head and neck into a bush, that the whole of their body is concealed."

There is no evidence that Vikings wore horns on their helmets. In fact, the image of Vikings wearing horned helmets stems from the scenography of an 1876 production of the Der Ring des Nibelungen opera cycle by Richard Wagner.

17. Humans and dinosaurs (other than birds) did not coexist. The last of the non-avian dinosaurs died 66 million years ago in the course of the Cretaceous–Paleogene extinction event, whereas the earliest members of genus Homo (humans) evolved between 2.3 and 2.4 million years ago. This places a 63-million-year expanse of time between the last non-bird dinosaurs and the earliest humans. Humans did coexist with woolly mammoths and saber-toothed cats—mammals which are often depicted alongside humans and dinosaurs.

18. Marco Polo did not import pasta from China, a misconception which originated with the Macaroni Journal, published by an association of food industries with the goal of promoting the use of pasta in the United States. Marco Polo describes a food similar to "lagana" in his Travels, but he uses a term with which he was already familiar. Durum wheat, and thus pasta as it is known today, was introduced by Arabs from Libya, during their conquest of Sicily in the late 7th century, according to the newsletter of the National Macaroni Manufacturers Association, thus predating Marco Polo's travels to China by about six centuries.

19. Houseflies have an average lifespan of 20 to 30 days, not 24 hours. The misconception may arise from confusion with mayflies, which, in some species, have an adult lifespan of as little as 5 minutes. A housefly egg will hatch into a maggot within 24 hours of being laid.

20. Older elephants that are near death do not leave their herd and instinctively direct themselves toward a specific location known as an elephants' graveyard to die.

It is true that life expectancy in the Middle Ages and earlier was low; however, one should not infer that people usually died around the age of 30. In fact, earlier low life expectancies were very strongly influenced by high infant mortality, and the life expectancy of people who lived to adulthood was much higher. A 21-year-old man in medieval England, for example, could by one estimate expect to live to the age of 64.

22. Computers running macOS or Linux are not immune to malware such as trojan horses or computer viruses. While Microsoft Windows has a much larger number of viruses developed for it, this is a consequence of its extremely large market share – specialised malware designed to attack macOS and Linux systems has existed for many years.

23. Egg balancing is possible on every day of the year, not just the vernal equinox, and there is no relationship between astronomical phenomena and the ability to balance an egg. The tradition of balancing eggs on a particular date originates in China, when it was reported on by Life magazine in 1945. However, it was reported in 1987 that Frank Ghigo was able to balance some eggs on every day from February 27 to April 3, 1984. At the same time, he also found that "...some eggs would simply never balance, on the equinox or otherwise.

24. The expression "rule of thumb" did not originate from a law allowing a man to beat his wife with a stick no thicker than his thumb, and there is no evidence that such a law ever existed. The true origin of this phrase remains uncertain, but the false etymology has been broadly reported in media including The Washington Post (1989), CNN (1993), and Time magazine (1983).

25. The daddy longlegs spider (Pholcidae) is not the most venomous spider in the world, and they can indeed pierce human skin, though the tiny amount of venom they carry causes only a mild burning sensation for a few seconds. In addition, there is also confusion regarding the use of the name daddy longlegs, because harvestmen (order Opiliones, which are arachnids, but not spiders), crane flies (which are insects), and male mosquitoes (also insects) are also sometimes called daddy longlegs in regional dialects, and may occasionally share the misconception of being venomous.