Humans are masters of navigation. Over the course of history, we’ve developed tools to help us explore not only Earth but other planets. Yet strip away all those tools, blindfold us, and tell us to walk in a straight line, and inevitably we become a directional mess, turning in tight loops. Many studies in the past century — though mostly informal — have cataloged this phenomenon again and again. Without some form of reference, such as a mountain, a building, or even the sun, humans are incapable of walking in a straight line, no matter how hard we try. It happens whether we’re blindfolded or just lost in the forest. So what’s going on?

The compass wasn’t originally used for navigation.

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The Chinese created the first compass — made with a lodestone — in the third century BCE. Early compasses were used for divination and other spiritual purposes rather than navigation, but eventually their useful wayfinding attributes won out.

We don’t know for sure, but scientists have been able to rule out some popular go-to explanations. Researchers from the Max Planck Institute for Biological Cybernetics in Germany discovered that body asymmetries (different-sized legs, right-handedness vs. left-handedness, etc.) didn’t account for such vast misdirection. Additionally, the idea that people can’t correctly calculate the movement of their legs doesn’t explain the tight-looped pattern. The Max Planck scientists theorize that with every blindfolded step, a very small directional discrepancy from a straight line is introduced, which then compounds with every additional step. Without the aid of visual references to unconsciously correct for these discrepancies, blindfolded people are poor at navigating a straight line, and will inevitably begin walking in tight-looped circles. While this theory explains why humans do this, scientists aren’t sure of the biological how (though they think errors in the inner ear may be to blame). For now, this straight-line conundrum remains one of the many mysteries of the human brain and body.

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The average adult blinks about 15 times a minute, whether to lubricate the eyes, clear unwanted irritants, or refocus attention. Babies, on the other hand, blink far less often — only two to three blinks per minute on average. So, why do infants blink less than adults? The answer may lie with our brain’s dopamine levels, which control human blinking. Scientists initially made connections between this feel-good neurotransmitter and blinking because people with schizophrenia, who usually have excess dopamine production, may blink more frequently. The inverse is also true — Parkinson’s disease, caused by damaged dopamine-producing neurons, makes people blink less often. So a baby’s infrequent blinking may be a clue about how the brain forms after we’re born, showing that a baby’s dopamine system is likely still forming and thus impacting blinking frequency. 

Birds blink just like humans.

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Like humans, birds have an upper and lower eyelid — but they also possess a third eyelid, known as a nictitating membrane. This transparent nictitating membrane sweeps sideways across the cornea, keeping it clean and moist. As a result, most birds don’t blink like humans do.

However, dopamine production is only one piece of the mystery. Scientists also theorize that because a baby’s eyes are small, they likely require less lubrication than adult peepers. Babies may also blink less often because it’s actually pretty demanding to be a baby, requiring more active attention to gather the necessary visual information for survival (and thus leaving less energy for blinking). So while babies may seem like pint-sized layabouts, they’re actually putting in a lot of work to become functioning and frequently blinking members of society. 

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The internet is unfathomably vast, but it’s also quite small. In fact, a researcher in 2006 found that in physical terms, it only weighed about 50 grams — roughly the same as three large strawberries. That estimate was updated to 141 grams in 2018, and as the internet continues to grow exponentially, we can assume it’s well on its way to the equivalent of a whole crate of strawberries. What’s actually being weighed in that calculation are the electrons inside the computer servers that make the internet run. The weight of that energy is considerably heavier than that of the actual stored data on the internet itself, which in 2007 was measured as low as 0.2 millionths of an ounce — about the same as the smallest grain of sand you can imagine. There are at least 100 million internet servers in existence, which weigh quite a lot when combined.

Strawberries are berries.

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They actually belong to the rosaceae (rose) family and have been called a “false fruit” by botanists.

These are all estimations, of course. The internet is growing at a rapid pace, and any calculations of its size — whether in terms of the information contained therein or the actual mass of the infrastructure — could quickly become outdated. Even so, the disparity between how simultaneously big and tiny the web can seem by different measurements remains striking.

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No two humans smell exactly alike, because odor is a complex medley of aromatic influences that come from our environment, genes, and various secretions; all of these add up to what’s known as our volatile organic compound (VOC). Gender can also be a differentiating factor, as a 2023 study from Florida International University discovered. As part of the experiment, 30 self-described men and 30 self-described women grasped cotton balls for 10 minutes in hands that hadn’t been washed for at least an hour. Those cotton balls were then analyzed using gas chromatography and mass spectrometry to identify the individual chemicals that made up the various VOCs of the participants. Using a type of data analysis known as chemometrics, the researchers were able to identify the gender of the participant based on their hand odor with stunning 96.67% accuracy. In other words, men’s and women’s hands seem to produce different odors. 

The bacteria that make body odor are good for you.

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Most human sweat is essentially odorless salt water, but when skin bacteria eat proteins in our sweat, they produce odor. Yet many of these stinky types of skin bacteria actually protect us from eczema, as well as from dangerous infections such as MRSA.

Such a fact aligns with a variety of evidence that humans have subtle aromatic differences. Diseases have particular smells (acute diabetes smells like rotten apples, for example) and diet can also play a role. One study even discovered that single males smell differently than their partnered counterparts, mainly due to differences in testosterone levels. As for our hands, this subtle chemical fingerprint could one day inspire new tools for forensic scientists to analyze crime scenes. But for now, our fragrant hands remain primarily an aromatic oddity.

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