Welcome to Discovery, your guide to the immense (and scientific) wonders of the world. This week, a look at nature’s most exquisite creation and why gastric cancer rates are rising in women. But first: the truth behind these mysterious feet that washed ashore along the Salish Sea.

PHOTOGRAPH BY REBECCA HALE AND MARK THIESSEN/NATIONAL GEOGRAPHIC IMAGE COLLECTION

In 2007, a 12-year-old girl spotted a lone blue-and-white running shoe on a beach in British Columbia. When she looked inside, she found a sock. Then, upon closer look, a foot. The next year, five more shoe-clad feet appeared on nearby Canadian beaches prompting all kinds of theories: Was it the work of serial killers? Aliens?

The truth, it turned out, was even more unexpected.  

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PHOTOGRAPH BY DAVID DOUBILET, NAT GEO IMAGE COLLECTION 

PHOTOGRAPH BY DAVID LIITTSCHWAGER 

If you ask someone how animals use their eyes, they’ll probably assume it’s the same way humans do. The answer is far more complicated than meets the eye. 

BEFORE YOU GO: Unravel the mysteries of the world’s most critical rainforest.

Today’s newsletter was edited and curated by Jennifer Baik and produced by Amanda Williams-Bryant. Thanks for reading!