Your fingerprints can predict some health issues. Looking at the sun can make you sneeze. You grow a new skeleton every ten years. Science hasn’t uncovered every mystery, but what it has discovered will blow your mind.
Science Knows Why ...
1. You get goose bumps. When you feel a chill or see something scary, your body releases a surge of adrenaline. The point is to make your body hair stand up—which helped our animal ancestors stay warm and also made them look larger in the face of predators. Getting those individual hairs to stand at attention requires the teeny skin muscles at the base of each follicle to contract, making your skin look vaguely like a goose’s postplucking—hence, goose bumps.
2. You grow wisdom teeth. Wisdom teeth are actually a third set of molars. They allowed our forebearers to munch on rough food such as roots, nuts, and meat, especially when other teeth fell out (alas, our ancestors had poor oral hygiene). About 35 percent of people never develop wisdom teeth, partly because of an evolutionary shift that means the human jaw is often too small for them. The rest of us start developing them by age ten, though they don’t fully emerge until young adulthood, which is when we (allegedly) acquire full-grown wisdom.
3. Your fingers and toes wrinkle in water. When you’re in the bath, water seeping into your skin makes the upper layers swell. That causes the blood vessels below to constrict, which in turn causes some of the upper layers of skin to collapse. The irregular pattern of swelling and falling skin is what we see as wrinkles on our fingertips and toes.
この記事は Reader's Digest US の June 2019 版に掲載されています。
7 日間の Magzter GOLD 無料トライアルを開始して、何千もの厳選されたプレミアム ストーリー、8,500 以上の雑誌や新聞にアクセスしてください。
すでに購読者です ? サインイン
この記事は Reader's Digest US の June 2019 版に掲載されています。
7 日間の Magzter GOLD 無料トライアルを開始して、何千もの厳選されたプレミアム ストーリー、8,500 以上の雑誌や新聞にアクセスしてください。
すでに購読者です? サインイン
Mom's Last Ball Game
Flipping to the Orioles turned into an inside-the-retirement-park home run
THE BITTER TRUTH ABOUT SUGAR (AND SUGAR SUBSTITUTES!)
It's no secret that Americans have a serious addiction. Here's how to cut back on the sweet stuff, once and for all.
Breaking Camp
Good campers leave no trace. Bad ones leave with hilarious stories.
"I HAD TO DO IT"
Americans are living longer, forcing loved ones to make impossible choices about their long-term care
GROWING Joy
Gardening yields endless rewards, from first sprouts to final harvest, and then the best part: sharing the bounty
I Tried It ...Exercises to Relieve "Tech Neck"
I STARE AT MY phone for five hours a day. At least, that's what an impertinent weekly notification tells me. As a result, I've developed \"tech neck❞— head forward, shoulders rounded and back slumped-and it causes pain in my back, shoulders and neck.
Eye Health Epidemic
What's behind the sharp increase in nearsightedness?
HOW TO DEFUSE A BOMB, ACCORDING TO MY MOM
OK, SWEETIE, NOW just stay calm and don't panic. I SAID DON'T PANIC. You're making me nervous.
Crazy for Curry
It's steeped in spice-and not the one you think
Ringing True
He thought his late parents' wedding bands were gone forever