Type Cast: The Japanese Fascination with Blood Types

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Actor Ken Watanabe was born in Koide, Niigata, Japan, on October 21, 1959. He was nominated for an Academy Award for his role in The Last Samurai, and has more recently appeared in Batman Begins and Inception. He survived leukemia, which he was diagnosed with in 1989, and has Hepatitis C. In 2004, he was featured in People magazine's issue listing the fifty most beautiful people. One can learn all of this from Watanbe's Wikipedia entry.

To learn his blood type, however, you will have to dig deeper. Not much deeper, though. That information is in his Wikipedia entry, too—his entry on the Japanese Wikipedia, that is. (For those who do not speak Japanese, here's a screenshot of it, translated. Pay particular attention to the infobox on the right, three lines up from the bottom.) He's blood type A.

Why is it there? Because Japanese culture treats blood types much like the Western world treats Zodiac symbols: mythical indicators as to people's personalities and, in relationships, to their compatibility with others. These blood type characteristics are shown at left. While science has widely debunked any causal connection here, an estimated 90% of Japan's residents know their blood types.

And blood type-related products are a good business in Japan. In 2008, four of the top selling books (seen here) in the country were "manuals" for people with a specific blood type — one for each possibility. One can also purchase condoms which, while functionally identical (thankfully), are colored and decorated in different ways, intending to match with some traits specific to the wearer's blood type. There are also soft drinks tailored to the drinker's blood type with, for example, Type AB drinks having extra magnesium in them, as a way to decrease the drinker's stress and play into their blood-borne strengths.

Of course, this "information" comes with a downside—discrimination. In 2006, the New York Times reported on a particular oddity: almost all of the Japanese-born American baseball players (except for Ichiro Suzuki) were Type Os. Japanese culture sees this group as the "warrior" archetype, leading some to believe that not being a Type O makes it harder for teams to sell fans on a player's skill. A 2008 article in the Guardian takes a more explicit stance, noting that blood type harassment (called "bura-hara") has lead to "bullying among kindergarten children, denying jobs to otherwise ideal candidates and ending happy relationships."

But the tradition continues—and even invades modern applications into everyday life. Sign up for a Facebook account using the Japanese interface and fill out your profile information. You will see the standard American options—name, birthday, gender, and whether you are romantically interested in men or women. And, as seen here (translated loosely, which explains "love object"), you'll also see a drop-down menu for blood type.
On June 13 of this year, someone in Japan put a watermelon up for sale and found a buyer—at a price just under $4,000 (in equivalent yen). The watermelon is a densuke watermelon—a rare type commercially grown only on the Japanese island of Hokkaido. Only 10,000 of these spotless, black watermelons (seen here—the inside is the familiar red) are harvested each year, and then annually one of the first ones is put up for auction, with the highest price ever topping $6,000. The watermelons typically retail for around $200.

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Wisconsin Department of Natural Resources
Why Is Ice Slippery?
Wisconsin Department of Natural Resources
Wisconsin Department of Natural Resources

If you’ve ever shakily stepped onto the ice at your local skating rink, you are intimately familiar with the fear of falling on slippery ice. But what makes ice so slippery in the first place? Interestingly enough, scientists are still trying to figure that one out.

Physicists used to believe that ice became slippery when it was exposed to applied pressure. This pressure, they theorized, lowered the melting temperature of the top layer of ice. They believed that when a person went ice skating, the pressure from the blade caused the topmost layer of ice to melt. The thin layer of water allowed the ice skate to glide easily over the surface. After the blade passed, the top layer of water refroze.

However, most scientists today claim that this theory is wrong. “Ice is a very mysterious solid,” Robert M. Rosenberg, a chemistry professor at Lawrence University, said in an interview with The New York Times.

Scientists found that while pressure does lower the melting point of ice, it only does so by a fraction of a degree. Instead, they proposed that the friction from an ice skate causes the ice to melt beneath it.

Others believe that ice naturally possesses a fluid layer comprised of unstable water molecules. While these molecules search for stability, they move chaotically over the ice’s surface and create a slippery layer.

Determining Migratory Patterns of Early Humans — With Earwax!

Dan Lewis runs the popular daily newsletter Now I Know (“Learn Something New Every Day, By Email”). To subscribe to his daily email, click here.

Earwax is mostly gross, but it serves a few purposes: protecting our ear canals from bacteria and dryness, assisting in cleaning and lubrication, and — surprisingly — helping anthropologists determine the migratory patterns of early humans.

While most native English speakers have wet, amber-to-brown colored earwax, there's a second type — dry, gray, and flaky. Which type of earwax you have is determined genetically, with the dry type being recessive and perhaps the result of a genetic mutation somewhere along the way. For some reason, the mutation is common among East Asians. An estimated 97 to 100 percent of people of European and African descent have the wet-type earwax, while 90 percent or more of those descended from East Asians have the dry type.

The gene that controls the relative wetness of earwax is tied to sweat, generally, and the prevailing belief amongst researchers is that the recessive gene, insofar that it reduces sweat output, had advantages in the colder climates of northern China (where, along with Korea, dry earwax is most common), where the mutation seems to have begun.

But for the rest of the world population, earwax makeup is mixed. Native Americans and people from southeast Asia, for example, exhibit dry earwax in 30 to 50 percent of the population, and it appears to occur more densely in some communities thereof than others. Armed with this information, researchers can determine in part the ancestral routes of different people and how those ancestors got to where their descendants now live.
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BONUS FACT: Whales' earwax increases over time without (mostly) discharging. This makes the amount of earwax in a whale's ear proportional to its age. As many whales (for example, baleen whales such as the blue whale, the world's largest mammal) do not have teeth, earwax buildup is one of the best ways to determine how old the whale is. For toothed whales and dolphins? Their teeth grow in layers and, much like the rings of a tree's trunk, the layers are used to determine the animal's age.

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