Archaeologists working in one of the most impenetrable rain forests in Guatemala have stumbled on a remarkable discovery: a room full of wall paintings and numerical calculations.
The buried room apparently was a workshop used by scribes or astronomers working for a Mayan king. The paintings depict the king and members of his court. The numbers mark important periods in the Maya calendar.
The room is about the size of a walk-in closet. It's part of the buried Maya city of Xultun. There are painted murals on three walls, depicting a resplendent king wearing a feather and four other figures. Maya paintings this old — the site dates to the ninth century — are very rare; tropical weather usually destroys them.
But David Stuart, an anthropologist at the University of Texas, Austin, says the numbers are the most intriguing discovery. "The wall is covered in numbers and this is something that really got our attention very early on," he says. "This is an unusual thing about the Xultun mural."
Stuart says some of the numbers are calendars that mark Maya ceremonies, or the cycles of the moon, Venus and Mars. Some calculations appear to be efforts to predict lunar eclipses.
"It's kind of like having a whiteboard in your office where you write down numbers you want to remember if you are a physicist or a mathematician," Stuart says. "And it's amazing it's on a wall. It's not in a book."
Maya numbers are written with bars and dots. Their use in calendars and astronomy is well-known from a Maya book called the Dresden Codex, which is written on the bark of a fig tree. But the Xultun murals are centuries older than the book.
Writing in the journal Science, the scientists say the murals confirm what Maya archaeologists have been saying for years: The Maya calendar does not predict the end of time in 2012, as some New Age prophets have argued. In fact, the murals register future time stretching far beyond 2012.
Archaeologist William Saturno from Boston University compares Maya calendars to a car's odometer.
"If we're driving a car," Satruno says, "we don't anticipate that at 100,000 miles the car will vanish from beneath us. We know that it will reset to zero, and the next 10th of a mile we go we'll have another number to look at."
What these Maya timekeepers were doing was simply marking the passage of time from past to future, but in discrete intervals.
The buried city of Xultun was discovered in 1915 but was so hard to get to that archaeologists mostly ignored it. Saturno started exploring it in 2008. A member of his team found the mural room two years later, under just a few feet of soil. They got an emergency grant from the National Geographic Society to dig into it.
Looters had stolen everything removable, but the murals and the numbers remained.
Saturno says there may be lots more to find at Xultun. They've examined only about 1 percent of the buried city.
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