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Native Americans on the western Great Plains were making and tossing dice 6,000 years before people in Africa, Asia and Europe, according to new research at Colorado State University.

Games of chance are considered to be the intellectual precursor to probability theory, statistics and scientific thinking.

Robert Madden, a doctoral student at Colorado State University and the report's author, said while trading relationships typically developed over many years, playing dice helped create trust on the spot.

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"This allowed people that didn't know each other well to come together," Madden explained. "Because they all understood the game and exchanged goods on a very fast basis without the need for those long-term relationships."

The earliest examples of dice were found at archaeological sites in Colorado, New Mexico and Wyoming, dating back 12,000 years to the Late Pleistocene Folsom period. Until now, scientists thought dice appeared only in complex Old World societies some 5,500 years ago. While kids and men tossed dice, Madden noted the historical record suggests 70% of players were women.

Unlike modern casino gambling where players compete against "the house," the games were entirely one-on-one. Madden pointed out ancient dice were made of bone or wood and were often oval or rectangular in shape. Many were flat, like a poker chip, while others were flat on one side and round or hollow on the other and they were always thrown in groups.

"Unlike, for instance, on a six-sided dice where the possible outcomes are one, two, three, four, five, six, you might throw five two-sided dice, you'd still get six possible outcomes but those outcomes are going to be zero, one, two, three, four, and five," Madden outlined.

Madden identified more than 600 dice from archaeological sites across North America, spanning from the end of the ice age to the time after European contact. He added they are still being used today.

"Usually if you've got something that was happening a few thousand years ago, it's exceedingly rare to see it continue," Madden acknowledged. "They are continuing. You can go on YouTube right now and find videos of groups getting together and playing these games."