Studying the language and culture of Mangareva, anthropologists at the University of Bergen in Norway found a mathematical system that appears to mix base-10 and base-2.
A tiny island 5000 kilometers south of Hawaii, Mangareva was first settled 1000 years ago by people using a decimal counting system. According to the University of Bergen's Andrea Bender and Sieghard Beller, though, the islanders added a binary element in the form of special counting words, all of which signified decimal numbers multiplied by powers of two. Bender and Beller realized that the Mangarevan system makes it possible to use binary arithmetic for calculations of large numbers.
“I was so thrilled that I couldn't sleep that night,” Bender says.