A mysterious new pyramid has been unearthed using laser scans of an ancient "lost city" of the Maya, in northern Guatemala.
Scientists using airborne light detection and ranging technology, or LiDAR, spotted signs of the ancient structure near Tikal, Guatemala's premier archaeological site.
The ruins of Tikal were abandoned more than a thousand years ago, and were rediscovered by a gum sapper in 1853.
Tikal was the capital of a warring state that became one of the most powerful kingdoms of the Maya.
But the new ruins were unusual, and different from the rest of Tikal, showing off the distinctive architecture found in Teotihuacan, more than 800 miles to the west.
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The complex – a pyramid – is thought to be a replica of a square at Teotihuacan known as the Citadel, National Geographic reports.
Stephen Houston of Brown University told National Geographic: “The similarity of the details was stunning”.
Further excavations found artefacts suggesting the site may have been a quasi-autonomous settlement within Tikal.
The city of Tikal flourished between 300 and 850AD, and was known to the Maya themselves as Mutul.
Edwin Román-Ramírez, director of the South Tikal Archaeological Project, said: “We knew that the Teotihuacanos had at least some presence and influence in Tikal and nearby Maya areas prior to the year 378.
“But it wasn’t clear whether the Maya were just emulating aspects of the region’s most powerful kingdom. Now there’s evidence that the relationship was much more than that.”
Research last year hinted at why Tikal’s inhabitants abandoned the city, finding toxic levels of pollution in reservoirs that suggested its water became undrinkable after droughts in the ninth century.
Researchers from the University of Cincinnati found toxic levels of mercury and algae in four central reservoirs in Tikal.
“The conversion of Tikal’s central reservoirs from life-sustaining to sickness-inducing places would have both practically and symbolically helped to bring about the abandonment of this magnificent city,” the study concluded.
Geochemical analysis found that two reservoirs nearest the city palace and temple contained extremely high and toxic levels of mercury.
The researchers traced the contamination back to a pigment the Maya used to adorn buildings, clayware and other goods.
During rainstorms, mercury in the pigment leached into the reservoirs, where it settled in layers of sediment over the years.
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