Earliest evidence for Maya calendar may have been found in Guatemala

By Carissa Wong.

The earliest evidence of the Maya calendar can be found in two pieces of an ancient wall. The fragments are decorated with a dot and line above a deer head and they are from a temple that was built between 2300 and 2200 years ago.

Several ancient communities living across the Americas tracked the time using cycles of 13 days and 20 days named after gods. 260 days before the cycle repeats, a specific day is assigned a number and a name in this calendar. The calendar is thought to have been used to decide when to hold ceremonies, mark important dates or predict future events.

Most previous evidence for calendar use by these ancient people was found on stone monuments. Evidence has been found that the Maya people may have used this calendar over a century earlier.

The San Bartolo archaeological site includes a pyramid called Las Pinturas, which was discovered in 2001. The Maya completed several phases of construction, with earlier structures eventually knocked down to form the foundations of the pyramid.

When the researchers sorted through the plaster collected from the pyramid's foundations, they realized that two pieces fit together to form a date symbol.

Stuart believes that this is the earliest example of the Maya calendar showing the day seven Deer.

Read more: Jungle festivals led to first Maya cities

The platform may have been used as an observatory for looking at the rising sun or other bodies in the sky. Stuart says it's like a kind of architectural clock.

The team dated the symbols to between 300 and 200 BC by using radiocarbon dating charcoal. Stuart believes that the symbols may have been used to reference a deity or a person.

Some archaeologists are unsure if this is the earliest evidence of the 260-day calendar. Mary Pohl at Florida State University believes that a previously discovered roller stamp from Mexico shows that the date was used in 500 BC. Stuart thinks the symbols on the stamp from 500 BC aren't a form of date notation like the Maya system.

There is clear evidence of the 260-day calendar use in this study. The University of Arizona's Takeshi Inomata says that this work is very important.

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