10 Facts About the World That Are Hard to Believe at First Sight (11 photos)
Are you sure you know how the world around you works? Are you willing to bet that the bear once had a completely different name, and that the book could be the result of a prank? 
The history of humanity and nature is full of incredible twists and turns: from literary hoaxes that became reality to animals that evolve before our eyes. This collection features 10 facts that sound like fiction, but are actually the pure truth.
1. The Superpower of the Selected 
A certain percentage of people can voluntarily tense their tensor tympani muscle to create a low, booming sound in their ears. This often occurs when yawning or squeezing their eyes tightly shut. This internal "thunder" serves to naturally muffle loud sounds, but some can activate it at will.
2. A very densely furred animal 
Muskoxen have an average hair follicle density of 42.8 ± 1.4 per mm², which is approximately 4,500 hairs per cm². By comparison, the average human has hair density of 125 to 200 per cm².
3. Characteristics of Metabolic Decline 
Metabolism doesn't actually decline steadily from age 20. A large-scale study published in the journal Science suggests that it remains stable from age 20 to age 60 and only begins to decline after that.
4. A Unique Animal 
Opabinia, an animal that lived 508 million years ago, had five eyes, a backward-facing mouth, and a proboscis tipped with a claw. When the Opabinia reconstruction was first shown at a scientific meeting, the audience burst into laughter.
5. Magic or Coincidence? 
In 1913, at the Monte Carlo Casino in Monaco, the roulette wheel landed black 26 times in a row. The odds of this happening were approximately 1 in 68 million. Players lost millions of francs betting against black, hoping that such a long streak of black would be followed by a long streak of red.
6. The Book That Never Was 
One prank led to the creation of a real book. Annoyed by the way bestseller lists were compiled, radio host Gene Shepherd urged listeners to ask in bookstores for "I, Libertine"—a novel that never existed. Fans spread the hoax so widely that Ballantine Books hired Theodore Sturgeon to write the book, publishing it in 1956.
7. Genghis Khan's "Arrow" 
An enemy archer who nearly killed Genghis Khan voluntarily confessed after the battle, rather than beg for mercy. Genghis Khan spared him, renamed him Jebe ("Arrow"), and he went on to become one of the greatest generals of the Mongol Empire and one of the finest cavalry commanders in history.
8. Strict Rules 
Ferrari has a set of rules that owners of their cars must follow. For example, criticism of the brand is discouraged, modifications through unofficial channels are prohibited, and resale is prohibited during the first year of ownership. Those who fail to comply face lawsuits and injunctions.
9. The Genius of Camouflage 
Nature has gifted baron butterfly caterpillars with perfect camouflage. Their appearance imitates a dry leaf down to the smallest detail—from the outline to the finest network of veins, making them virtually invisible to predators.
10. A False Name 
Once upon a time, the bear had a real name, which we will never know. Our ancestors believed in the magic of words and were afraid to speak them out loud, lest they invite the predator himself. Thus, the dangerous beast became simply "the one who eats honey"—"the bear." A similar fate befell the snake. Its original name was lost, and a new one emerged from the word for "earth"—as in "crawling on the ground."
