From Vanishing Dots to Piggy Banks: This Week's Curios

Every day of the year, CEO Justin Kitch writes a quirky fact, known as the Daily Curio, intended to tickle the brains of lifelong learners everywhere. This is a weekly digest.

Last week's Curios covered illusions to trick your brain, boozy physics thought experiments, and piggy bank etymology.

Curio No. 1158 | Sound illusions
In yesterday's Curio, we discussed an amazing optical illusion. Now check out this amazing auditory illusion. In 1974, a musicologist named Diana Deutsch developed the scale illusion. In the scale illusion, two separate parts play a seemingly unrelated line of quarter notes. Each part is then separated in a stereo mix so that the left audio channel plays one part, and the right audio channel plays the other. When you listen to the channels mixed together on headphones, the brain does something amazing: it turns the two parts into perfectly ascending and descending scales. Listen for yourself below--headphones recommended... keep reading.

Curio No. 1157 | Vanishing dots, internet destroyer of 2016
And you thought the blue and black dress was cool. Here's an optical illusion that will blow your mind--not to mention hurt your eyes. The image was designed by vision scientists and originally published in the journal Perception. It shows 12 black dots on a gray grid. But our eyes can only see at most one row of four dots at a time--as we refocus on new rows, we lose sight of dots previously visible. It's really better if you see for yourself below! Images like this one, known as grid illusions, have been around for a while. The first one was created by German physiologist Ludimar Hermann in 1870, and is known as a Hermann Grid.... keep reading.

Curio No. 1156 | Quiet as a mouse
Shh, listen to this. There is now scientific proof that silence is golden. Mice subjected to two hours of silence per day experience cell growth in the hippocampus, the brain's memory center. The researchers tested silence against several other sound stimuli--ambient sound, white noise, recorded calls of mice pups, and Mozart's piano sonatas--all of which caused new cell development, except for white noise. But only the cells grown in silence were integrated into the brain after seven days. The new finding complements other studies showing silence benefits blood pressure and positive self-image. Unfortunately silence is rare here at Curious World HQ... keep reading.

Curio No. 1155 | The drunkard's walk
Physicists have a long history of creative "thought experiments" that illustrate important principles. For example: Schroedinger's cat, the plum pudding model, and the spherical cow. But my personal favorite is the drunkard's walk. It likens the motion of a molecule to a drunk man walking around an unfamiliar city. Each step he makes is completely random: he could go backward, forward, or any direction in between. Yet, if you follow the drunkard around town, he always moves farther from his starting point over time. Why? Common sense say it's just as likely--given a completely random route--that he would end up where he started? But it's not true. The first step must move the drunkard away from the starting point... keep reading.

Curio No. 1154 | Clever pirate patches
Pretty much every stereotype you knew about pirates is made for Hollywood: the peg leg, gruff men always saying "arr matey," the Jolly Roger flag, maps of buried treasure. Except for one. Historians think pirates may have actually worn eyepatches for a very practical reason: to preserve night vision. Pirates' eyes were subjected to extreme changes in light conditions because of their life at sea. While the insides of ships were likely pitch black at all hours, on the decks the sun was shining brightly. For extreme changes from bright to dark, and vice versa, eyes can take up to 25 minutes to recover full functionality... keep reading.

Curio No. 1153 | Breaking the piggy bank myth
What's the story with piggy banks? The need for a secret place to hide coins is self-explanatory--especially for anyone with siblings. But why the pig? Many amateur etymologists have latched onto an urban legend about the piggy bank from the 1965 book How Did It Begin? The author states that the Old English word for clay was pygg. People had been using clay jars to store money since B.C.E, thus they were using "pygg jars." Over time pygg jars became piggy jars became piggy banks. From there all it took was one clever potter and voila, little banks shaped like actual pigs. If that sounds like a little too good of a story, it probably is... keep reading.

Curio No. 1152 | Slimy politicians
Here in the US, we're used to our modern-day politicians being a little slippery. But now there is news that two of the giants in American history, Jefferson and Lincoln, are marred with slime. Literally: the Jefferson and Lincoln Memorials in Washington D.C. are infested with slime. The black stuff, called biofilm according to the National Park Service official euphemism, has been growing on the dome of the Jefferson Memorial since 2006. It has also been found on the Lincoln Memorial, the Congressional Cemetery and the D.C. War Memorial. It's made up of clingy microorganisms and it is common on stone surfaces, especially marble.... keep reading.

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