Ever heard that a daddy longlegs' bite is incredibly venomous, but its fangs can't pierce your skin? Or that you'll get warts from handling a toad? Well, those are both common misconceptions, though plenty of people think they're true. Here are a few more "facts" that...aren't.
1) Humans register the four flavors on different parts of the tongue
First, humans can taste five basic flavors, not four (sweet, sour, bitter, salty, and umami, like soy sauce). Secondly, the idea of the tongue map comes from a poorly performed experiment from the early 1900s. It's been proven wrong over and over since then. (Put some salt on the tip of your tongue and you'll see for yourself.)
2) The Great Wall of China is the only human-made object visible from the moon
Little of Earth is visible from the moon except the oceans, the continents, and some clouds, so spying the Great Wall of China would take a bit more than eagle eyes. Even from only 180 miles up (since "space" is a rather nebulous term), the Great Wall is pretty much invisible. So what human-made objects can you see from space? Things like highways, airports, and large dams.
3) Chameleons change color as camouflage
While the cuttlefish might change color to blend in (and the mimic octopus can even change the texture of its skin!), the humble chameleon changes color to signal mood, aggression, light intensity, territory, and mating behavior, despite what cartoons would have you believe. In other words, a chameleon's impressive color-changing abilities are just an extremely flashy form of communication, not a way to hide it from prey or predators.
4) Vikings wore horned helmets
Although people from many different cultures around the world have worn horned helmets (usually as ceremonial forms of headwear), the Vikings, ironically, weren't one of them. This "fact" comes to us from the 1876 production of Wagner's Der Ring des Nibelungen. In other words, a costume designer thought some characters would look neat with horned helmets, and the idea that Vikings wore horned helmets spread from there.
5) Swimming within an hour of eating increases your chances of drowning
The idea behind this misconception is that eating supposedly diverts energy or blood from the muscles to the stomach to aid in digestion. Strenuous exercise while digesting food then leads to cramps, which then leads to drowning. Though the idea feels like common sense, it's completely false. Swimming after drinking alcohol, on the other hand...not such a great idea.