By Brittany Callan
Vista Alegre, Mexico – Exploring an overgrown Mayan temple in the old Mayan port city of Vista Alegre – located on an island off the coast of the Yucatan Peninsula – wasn’t quite what I expected. Videogames such as Uncharted, Tomb Raider, Assassin’s Creed: Black Flag set up romantic over-the-top temples that I’m sure are responsible for my love of crumbling ancient ruins. I knew better than to expect environments resembling the ones portrayed in my fantasies. But I don’t have an archaeologist’s trained eye – I wouldn’t have been able to notice an archaeological pit on my own.
We were stopping at the island so that Northwestern University geologist Patricia Beddows could check on and replace some of the flow and temperature sensors she had deployed nearby. She is an associate professor of instruction in Earth and Planetary Sciences at Northwestern and has spent years researching in the Yucatan. She decided to give a tour of the archaeological site while we were here. I was following Beddows for an embedded reporting assignment.
The pits are typically divided into units, a meter square and 10 centimeters deep. Archaeologists and their students sift and sort all of the material dug out of the pit, once used by the Mayans as storage chambers. Anything that isn’t just geological material gets carefully collected and this includes pottery, shells and bones. The rest of the material is put back into the pit at the end of the digging season and then covered up to look like the rest of the jungle floor. There are about 20 to 30 pits at Vista Alegra and almost all of them included some human remains, showing that the island didn’t have enough room for people to bury their dead. All of the artifacts and remains are gathered for safe-keeping at a building owned by the multinational archaeologists who work on the site.
The site has a couple of different holes in the ground that are built by the Maya on high points. These holes, called “chultun,” were used for water or food storage. However, because they are on high points, it seems unlikely that they were used to capture water, leaving a mystery as to where the people living on the island got their water. People lived at the site intermittently from 800 B.C. to the mid-16th century. Beddows lived on this site for a month at one point and says her group of a small number of people had challenges maintaining a water supply. Hundreds of people lived on this island in ages past. It served as a connection point between coastal and inland areas on a trade route for Mayan freight canoes. Beddows says the site might lead to a piece in the basic equation of the area’s water budget that scientists are currently missing. There might have been areas of coastal freshwater discharge that the ancient people could use.
One chultun goes deeper than the current water table where archaeologists were still finding material. This material had clearly been on dry land when it was used, but it now is flooded by groundwater. Beddows says that this might mean there is something scientists are missing about how the sea level has changed over time.
“There’s something here we don’t fully understand,” she says. The site challenges what scientists currently accept about the tectonic stability in the area. The archaeology at this site and at others nearby are forcing a fundamental rethinking of tectonic stability, which has been assumed to exist since a paper published in 1970. Beddows compares the potential movement to a teeter totter where parts of the platform are rising while others are dropping. This could mean that what looks like sea level rise actually is the land going down, or the opposite, which would inform the way adaptions measures to climate change are implemented.
We wander for a bit on the pathways that have been cleared for researchers as we look for the central pyramid. A massive, beautiful carved stone of a snake head used to lie in front of the temple but was taken away by the National Institute of Archaeology out of concern that it would be stolen. Looting – even in a remote site such as this one, only accessible by hiring a fishing boat – is still a real risk. We find the pyramid, which is actually next to a plaza we encountered earlier. The pyramid, after centuries of erosion, looks like a pile of worn rock with weeds growing out from between them. When it was first created, the outside of it would have been plaster. The pyramids at popular tourist sites once also looked like this before clearing the vegetation and putting surface stones back in place.
We scramble up the rocks to the top, where we can see above the treetops of the jungle. The pyramid is extremely steep. Beddows says the reason for that is because it reduces the total volume of building materials needed to create it, which is important when all of the rock on the island would have been moved here from somewhere else. The only methods of transport meant carrying the rocks or bringing them by canoe, both of which would have been difficult.
“It actually made more sense for them to invest in making more cement, which is made by burning lime,” requiring wood and labor, Beddows says. “But that’s probably easier than hauling rocks.”
We carefully walk sideways down the pyramid, sliding and trying not to knock any of the rocks out of place or erode them. We leave the scientific mysteries of the site behind us, where it awaits the next expedition of researchers to visit.