Mental Floss

BIG QUESTIONS

There's a legitimate reason, and it isn't purely aesthetic.

Natural rubber is white, and so were the earliest car tires. So, why are modern-day tires black? The answer is linked to Crayola and carbon black.

Jake Rossen
The bow of the USS ‘Samuel B. Roberts,’ lying more than 4 miles under the surface of the Pacific Ocean.

These are the five deepest shipwrecks ever discovered, including the USS ‘Samuel B. Roberts,’ which went to the depths of the Philippine Trench during the Second World War.

Tim Brinkhof






“Say uncle!”

One theory says it comes from an Irish word; another says we have the ancient Romans to thank. But the joke is on those theories, because the real story is more complicated than that.

Kara Kovalchik, Erin McCarthy










It's not whipped cream.

Cool Whip’s ingredients aren’t a total mystery—but they’re also not as simple as cream and sugar.

Ellen Gutoskey
A supermarket poultry case containing packages of raw chicken.

Salmonella, norovirus, and other germs are often found in raw poultry and fresh produce—and can find their way into your digestive system. Here’s what to know about the symptoms and treatments for food poisoning.

Jake Rossen




Cinco de Mayo, or May 5, is recognized around the country as a time to celebrate Mexico’s cultural heritage. Like a lot of days earmarked to commemorate a specific idea or event, its origins can be a little murky. Who started it, and why?

Jake Rossen


NASA officially prohibits alcohol aboard its missions, but that didn’t stop some American astronauts from enjoying a wee nip with their Russian colleagues.

Nick Keppler


A crowd of workers gathered at a May Day event in New York City, early 20th century.

May Day isn’t just for Maypole-dancing anymore. Here's how May 1 evolved from a pagan holiday to a communist day of remembrance.

Michele Debczak
There have been 23 Pope Johns, but only one Pope Francis.

For centuries, men assuming the top job in the Roman Catholic Church kept their birth names. That changed with Pope John II.

Paul Park
An aerial view of a sinkhole in Wales that appeared in December 2024.

Sinkholes have gulped down suburban homes, Corvettes, the White House lawn, a sizable chunk of Louisiana, and even people. How does the ground just open up like that?

Roma Panganiban