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Do People Really Walk in Circles When They’re Lost?

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It’s a reliable movie trope: Our heroes are lost in the woods, and in their valiant effort to make a beeline out of the forest or back to camp or civilization, they inevitably get turned around and wind up back at the same spot where they began.

When a science television show approached Jan Souman, a research scientist at the Max Planck Institute for Biological Cybernetics, with a viewer’s question about the phenomenon, Souman wasn't sure if people actually did accidentally circle back. When lost, he thought, people would probably veer left or right randomly, but not actually circle back.

To find out, he and his research group gathered nine volunteers and stuck six of them in a German forest and the other three in the Tunisian desert. All of them were instructed to walk as straight as possible in one direction for several hours while wearing GPS receivers so that the researchers could analyze their routes.

Course Correction

Souman found that all of them eventually veered off course, and more than half did end up circling back to cross their own paths without realizing it. There was an interesting twist, though. The circling only happened with the four of the forest walkers who made their journeys in overcast conditions and the one desert walker who walked on a night with no visible moon. Those who could see the sun or moon managed to travel in straighter lines and, when they did lose their way, moved as Souman had predicted, veering left and right while generally going in the same direction and not crossing back on their route.

In a second experiment, the researchers had 15 volunteers try to walk in a straight line for an hour while blindfolded. When they couldn't see at all, the walkers circled back sooner, more often, and in tighter arcs, sometimes making a circle about the size of a basketball court.

The two experiments cast doubt on an older idea that this kind of disorientation comes from biomechanical asymmetries—like a differences in length or strength between the left and right legs—that create small but consistent directional bias. That would cause a person to consistently veer off in the same direction, especially when the person is blindfolded and without visual cues to compete with the bias. But only three of the walkers had a tendency to veer in one direction, while the others varied wildly in their circling, with their paths looking like a child had scribbled on a piece of paper. Walking in circles, Souman and his team think, isn’t caused by some physical bias, but an uncertainty about where straight ahead lies that increases over time.

Visual Clues

For the walkers in the first experiment, visual cues appeared to be very important. Those who could see some external reference point—the sun, the moon, a hill in the far distance—could use it to recalibrate their sense of direction and maintain a relatively straight path. (Interestingly, Souman notes that the volunteers in the first experiment walked for several hours, during which the sun moved about 50 to 60 degrees; rather than following a correspondingly bent path, they were able to correct for this, even if subconsciously.)

The volunteers who walked when it was cloudy or dark or while they were blindfolded didn’t have this luxury and walked in circles. Without a reference point to maintain their course, these subjects had to rely on other cues, like sounds and information from the vestibular system, which aids in movement, balance and spatial orientation. Small random mistakes in the processing of these cues, Souman and team think, add up over time, especially when the senses are limited. Eventually, the internal compass fails and “random changes in the subjective sense of straight ahead” lead a person off the straight and narrow path and right back where they started from.

Big Questions
Where Should You Place the Apostrophe in President's Day?

Happy Presidents’ Day! Or is it President’s Day? Or Presidents Day? What you call the national holiday depends on where you are, who you’re honoring, and how you think we’re celebrating.

Saying "President’s Day" infers that the day belongs to a singular president, such as George Washington or Abraham Lincoln, whose birthdays are the basis for the holiday. On the other hand, referring to it as "Presidents’ Day" means that the day belongs to all of the presidents—that it’s their day collectively. Finally, calling the day "Presidents Day"—plural with no apostrophe—would indicate that we’re honoring all POTUSes past and present (yes, even Andrew Johnson), but that no one president actually owns the day.

You would think that in the nearly 140 years since "Washington’s Birthday" was declared a holiday in 1879, someone would have officially declared a way to spell the day. But in fact, even the White House itself hasn’t chosen a single variation for its style guide. They spelled it “President’s Day” here and “Presidents’ Day” here.

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Maybe that indecision comes from the fact that Presidents Day isn’t even a federal holiday. The federal holiday is technically still called “Washington’s Birthday,” and states can choose to call it whatever they want. Some states, like Iowa, don’t officially acknowledge the day at all. And the location of the punctuation mark is a moot point when individual states choose to call it something else entirely, like “George Washington’s Birthday and Daisy Gatson Bates Day” in Arkansas, or “Birthdays of George Washington/Thomas Jefferson” in Alabama. (Alabama loves to split birthday celebrations, by the way; the third Monday in January celebrates both Martin Luther King, Jr., and Robert E. Lee.)

You can look to official grammar sources to declare the right way, but even they don’t agree. The AP Stylebook prefers “Presidents Day,” while Chicago Style uses “Presidents’ Day.”

The bottom line: There’s no rhyme or reason to any of it. Go with what feels right. And even then, if you’re in one of those states that has chosen to spell it “President’s Day”—Washington, for example—and you use one of the grammar book stylings instead, you’re still technically wrong.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at

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Big Questions
How Do You Steer a Bobsled?
 Quinn Rooney, Getty Images
Quinn Rooney, Getty Images

Now that the Olympics are well underway, you might have developed a few questions about the games' equipment. For example: How does one steer a bobsled? Let's take a crack at answering this pressing query.

How do you steer a bobsled?

Bobsled teams careen down an icy, curving track at up to 90 miles per hour, so steering is no small concern. Drivers steer their sleds just like you steered your childhood sleds—by manipulating a pair of ropes connected to the sled's steel runners. The driver also gets help from the rest of the crew members, who shift their weight to aid with the steering.

Why do speed skaters wear glasses?


Speed skaters can fly around the ice at upwards of 40 mph, so those sunglasses-type specs they wear aren't merely ornamental. At such high speeds, it's not very pleasant to have wind blowing in your eyes; it's particularly nightmarish if the breeze is drying out your contact lenses. On top of that, there's all sorts of ice and debris flying around on a speed skating track that could send you on a fast trip to the ophthalmologist.

Some skaters also say the glasses help them see the track. American skater Ryan Bedford recently told the Saginaw News that his tinted shades help him focus on the track and filter out distracting lights and camera flashes from the crowd.

What kind of heat are the biathletes packing?

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As you might guess, there are fairly strict rules governing what sort of rifles biathletes carry on the course. They are equipped with guns chambered for .22 LR ammunition. The gun must weigh at least 3.5 kilograms without its magazines and ammunition, and the rifle has to have a bolt action or a straight-pull bolt rather than firing automatically or semi-automatically.

Is a curling stone really made of stone?

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You bet it is, and it's not just any old stone, either. Curling enthusiasts swear by a very specific type of granite called ailsite that is only found on the Scottish island of Ailsa Craig. Ailsite supposedly absorbs less water than other types of stone, so they last longer than their competitors.

Ailsa Craig is now a wildlife sanctuary, so no new ailsite has been quarried since 2002. As a result, curling stones are incredibly expensive. Kays of Scotland, which has made the stones for every Olympics in which curling has been an official event, gets prices upwards of $1,500 per stone.

What about the brooms?

The earliest curling brooms were actual brooms made of wood with straw heads. Modern brooms, though, are a bit more technologically advanced. The handles are usually made of carbon fiber, and the heads can be made of synthetic materials or natural hair from horses or hogs. Synthetic materials tend to be more common now because they pull all of the debris off of the ice and don't drop the occasional stray bristle like a natural hair broom might.

What are the ski jumpers wearing?

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It may look like a ski jumper can pull on any old form-fitting bodysuit and hit the mountain, but things are a bit more complicated than that. Their suits have to be made of a spongy material and can't be thicker than five millimeters. Additionally, the suits must allow a certain amount of air to pass through them; jumpers wearing suits without sufficient air permeability are disqualified. (This rule keeps jumpers from wearing suits that could unfairly act as airfoils.) These rules are seriously enforced, too; Norwegian skier Sigurd Petterson found himself DQed at the 2006 Torino Games due to improper air permeability.

Those aren't the only concerns, though. In 2010, judges disqualified Italian jumper Roberto Dellasega because his suit was too baggy.

What's up with the short track speed skaters' gloves?

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If you watch a bit of short track speed skating, the need for gloves quickly becomes apparent. When the skaters go to make passes or careen around a turn, they need the gloves to keep from cutting their hands due to incidental contact with other skaters' blades.

There's more to the gloves than just safety, though. Since the skaters' hands often touch the ice during turns, they need hard fingertip coverings that won't add friction and slow them down. The tips can be made of any material as long as it's hard and smooth, but you've got to give American skater Apolo Ohno some style points for the gold-tipped left glove he broke out in 2010.


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