Real or Myth?
14 Popular Claims, Checked

True only for the sharks called obligate ram ventilators, which include great whites, makos and whale sharks: they have lost the ability to pump water over their gills, and would die from lack of oxygen if they stopped swimming. Sharks such as nurse and bullhead sharks use their mouth muscles to draw water over their gills, so they can breathe while lying still. Some, such as the tiger shark, can switch between the two.

SOURCE Joseph Castro, Live Science, 29 May 2013.

Swallowing one is possible, but "it would be a strictly random event". A sleeping person breathes, has a beating heart and may snore, all of which make vibrations that warn spiders off. The correction has its own twist. The story that the statistic was invented in 1993 by a columnist called Lisa Birgit Holst, writing in PC Professional, is also made up: the magazine and the columnist do not exist, and her name is an anagram of this is a big troll.

SOURCE Scientific American, quoting Rod Crawford of the Burke Museum; Snopes, on the invented origin story.

Generally not to the unaided eye from low Earth orbit. One of its wider parts might be about ten metres across, and NASA's chief scientist for Earth observation said the wall's materials are "similar in color and texture" to the land around it. Yang Liwei, China's first astronaut, flew on Shenzhou 5 in October 2003 and said afterwards that the Earth looked "very beautiful", but "I did not see the Great Wall from space." A NASA astronaut later photographed sections of it from the space station with a 180mm lens; he said he did not see it himself.

SOURCE People's Daily, 17 October 2003; NASA, 9 May 2005; Phil Plait, Scientific American, 2024.

Shown the claim in a newspaper column in 1935, he replied: "I never failed in mathematics. Before I was fifteen I had mastered differential and integral calculus." His school-leaving certificate from Aarau, dated 3 October 1896, gives him a 6, the top mark, in algebra, geometry, descriptive geometry and physics. He did fail the entrance exam for the Zurich Polytechnic in 1895, but on the non-science subjects, French especially, and he was two years younger than the other applicants.

SOURCE Walter Isaacson, TIME, 2007; his 1896 certificate; ABC Science, 2004.

The line is in Rousseau's Confessions, Book VI, where he recalls the saying of "a great princess" who, told that the peasants had no bread, answered qu'ils mangent de la brioche: let them eat brioche. He names no princess. He wrote that part around 1767, and Marie Antoinette only came to France from Austria in 1770.

SOURCE Rousseau, Confessions, Book VI; The Phrase Finder.

Cattle have two kinds of colour-sensing cone, not three: they are dichromats, and colour-blind to red. What draws the charge is the movement of the cape. Bulls charge the larger cape, the capote, just as hard, and it is magenta on one side and gold or blue on the other. In a 2007 television test, a bull went after two moving cowboys and left alone a person in red who stood still.

SOURCE Jacobs, Deegan and Neitz, Visual Neuroscience, 1998; Live Science.

The only Viking-age helmet preserved whole, from a warrior's grave at Gjermundbu in Norway, has no horns, and no contemporary source mentions Vikings wearing horned headgear, according to the National Museum of Denmark. The museum does note horned figures in some art of the period, and that such headgear may have been worn for display or ritual; in battle, it says, horns "would get in the way". The popular image took off in 1876, when Carl Emil Doepler designed the costumes, horned helmets included, for Wagner's Der Ring des Nibelungen at the Bayreuth Festival.

SOURCE National Museum of Denmark; Snopes; museum-digital on Doepler.

In experiments at the University of Plymouth, goldfish learned to push a lever for food, and when the lever worked for only one hour a day, they learned to press it at the right time. They can keep memories for at least three months. None of the sources we read points to any study that found three seconds.

SOURCE BBC Wildlife (Discover Wildlife).

Milk is usually at the back. Why is argued both ways. A dairy buyer told NPR's Planet Money in 2016 that it is there "because that's where milk comes in", so the cold chain is never broken, and called the walk-past-everything idea "a consumer misconception". On the same programme the food writer Michael Pollan argued that shops are laid out to make you cover ground, and a supermarket consultant called the walk past other goods a "side benefit". Both reasons can be true at once.

SOURCE NPR, Planet Money, episode 555, 21 September 2016.

The behaviour is real; the reason is not shown. Bison face into winter storms, while cattle tend to drift with the wind and can end up trapped in the corners of fenced pastures. A bison specialist told Snopes that bison face into the storm more than they walk into it, and there is no evidence that they know it gets them through faster. The Canadian Bison Association's explanation is insulation: facing the storm keeps snow and cold air from blowing under their coats.

SOURCE Snopes (rated it a mixture).

The idea has been credited to him for a long time, but no record from Napoleon himself has turned up. The earliest version we found is in 1827, in a life of Napoleon that the Swiss general Antoine-Henri Jomini wrote in Napoleon's own voice: quand l'ennemi fait un faux mouvement, il faut se garder de l'interrompre (when the enemy makes a false move, take care not to interrupt him). Archibald Alison's 1836 history, citing Jomini, turned it into dialogue: "when the enemy is making a false movement we must take good care not to interrupt him." The wording "making a mistake" is attributed to him in print by 1888. One fact-check rates the attribution correct on the strength of the 1827 book; we leave it unverified because that book was written by Jomini, in Napoleon's voice, not by Napoleon.

SOURCE Jomini, 1827; Alison, 1836; Quote Investigator; Snopes.

It often strikes the same place again and again, especially tall, pointed, isolated objects. The US National Weather Service says the Empire State Building is hit an average of 23 times a year.

SOURCE US National Weather Service, "Lightning Myths".

"We use virtually every part of the brain, and that [most of] the brain is active almost all the time," the Johns Hopkins neurologist Barry Gordon told Scientific American. The brain is about three percent of body weight and uses about 20 percent of the body's energy. The same article allows that at a given moment of rest only a small part may be busy; the myth is that the rest is never used.

SOURCE Scientific American, quoting Barry Gordon.

This one holds up. Honey is very low in water, acidic (a pH of roughly 3 to 4.5), and contains small amounts of hydrogen peroxide made by an enzyme from the bees, so very little can grow in it. "As long as the lid stays on it and no water is added to it, honey will not go bad," Amina Harris of the Honey and Pollination Center at UC Davis told Smithsonian. It can crystallise; that is not spoiling. One caveat that matters: the NHS says not to give honey to babies younger than 12 months, because it can contain the bacteria that cause botulism.

SOURCE Smithsonian, 2013; NHS, "Botulism".