One of the great advantages of LiDAR is that it can even show familiar sites in a new way. Near the iconic plazas at Tikal (above), this 3D rendering reveals that two features once thought to be natural, are instead further examples of the pyramids that punctuate the site (Inset).
to allow ritual parades within a town by connecting different pyramid groups. But in some areas, you also have these really long causeways that link different sites. In some cases, they run right off the edge of our data, and we don’t even know what they’re connecting to. So there are definitely Maya superhighways out there!’
‘Another surprise came from the bajos. These are huge depressions in the geology of northern Guatemala; bajos means “low” in Spanish. They are basically nasty seasonal swamps, so when it’s raining they fill up, but we never thought that they were particularly productive for the Maya. There was some evidence that soil at the very edge of the bajos would be collected and used elsewhere, but we certainly didn’t expect there to be much in the middle of these things. On the LiDAR data, though, we can make out grids and networks of canals and what we think are field systems. Even when you go out and look at these anomalies on the ground, the features are so subtle that you couldn’t be sure they were real without the LiDAR
demonstrating that these reticular patterns exist. We know from work in Belize that the Maya exploited wetlands there, so they must have found a way to use these swamp systems too. It fits really nicely, because when you see 60,000 new structures, one of the first questions you ask is “How did they feed all of these people?” So it’s really good to have that addressed too.’
Classic palimpsest Of course, the Maya period does not represent a single moment in time. Instead, the LiDAR data compresses thousands of years of culture into a single image of the landscape. Most of the new structures are believed to belong to what is known as the Classic period, which stretched from around AD 250-1000. As its name implies, this was the period when Maya society reached its zenith, so it seems a reasonable working model that this was also the time when they left the biggest footprint on their jungle home. Even so, the beginning of the Classic period used to be tied to
Re h a k at ya s i m e / M
st re a m
: D
P H OTO
major innovations, including the raising of glyphic inscriptions, but, as is so often the way, fresh archaeological discoveries have blurred such clear distinctions. One painted inscription, for example, has been radiocarbon dated to the 3rd century BC, suggesting literacy centuries before the Classic period. This is just one of many signs that the Preclassic period, running from c.2,000 BC-AD 200, was not just a lacklustre prelude for the marvels to follow, but an era that was cosmopolitan and complex in its own right.
‘In some areas, including near El Zotz, there are Preclassic settlements, and you can tell the difference’, says Tom, ‘because the structures look very different. There are rounded, more eroded shapes, which look kind of like pimples on the landscape, and stand out against the hard, angular shapes created by Classic structures. So there are places where the LiDAR lets you start to make a nice distinction. One thing that I have been looking at is a Preclassic settlement between El Zotz and Tikal, called
18
CurrentWorldArChAeology
Issue 96
