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(CNN)Evidence of ancient hybrid camels has been uncovered by archaeologists who were working to restore a temple in northern Iraq damaged by ISIS.
The Temple of Allat, which dates to the second century AD, is located in the city of Hatra, a UNESCO World Heritage site. Once a sprawling metropolis, it served as the capital of the Kingdom of Hatra. The remains of the ancient city were heavily vandalized by religious extremists between 2015 and 2017. Before that, the temple had also suffered decades of neglect.
During restoration after the recent damage, researchers spied something unexpected in a frieze above a door of the Temple of Allat. The horizontal stone piece of artwork appeared to show hybrid camels that resulted from crossing two different breeds.
The depiction of these camels has helped researchers gain a better understanding of ancient Hatra, which was a small neighboring kingdom of the Roman and Parthian empires -- though those neighbors were often more hostile than friendly.
The artwork also adds to the growing evidence that researchers have of when and where camel hybrids were bred. Previously, researchers believed different types of camels were crossbred primarily in expansive empires. This latest finding shows the practice was more widespread.
"The image appears to express a precise message -- the direct involvement of the king in camel herding, management and hybridization practices," said Massimo Vidale, an associate professor at the Università degli Studi di Padova in Italy.
Breeding hybrids of a sacred animal
The artwork was added to the temple during a renovation conducted by King Sanatruq I and his son, Abdsamiya in 168 AD, the researchers believe. It was during this time that the royals rededicated the temple to the goddess Allat, in addition to erecting nearly life-size statues of themselves.
Previous research on the stone frieze suggested that it depicted eight dromedaries, with two Bactrian camels in the middle.
Dromedaries are Arabian camels that sport one hump. These swift animals are ideal for riding or even racing. In contrast, Bactrian camels are native to Central Asia and have two humps. These hardy pack animals can withstand high altitudes, cold temperatures and even drought.
When Vidale and his colleagues took a closer look at the artwork, they noticed that the faces and fur of the two so-called Bactrian camels actually looked more like a cross between a Bactrian camel and dromedary.
And rather than a sizable space between the two humps, there was just a slight indentation -- a trait that has been observed in hybrids of these camel breeds.
People have been breeding camels since the first century AD, according to the oldest hybrid camel animal skeletons recovered from the Roman and Parthian empires.
This husbandry practice went into effect thousands of years ago because it leads to stronger and more resilient animals. Hybrid camels could carry double the load of dromedaries and more than double what a Bactrian camel could support.
Despite its diminutive size when compared with the surrounding empires, the kingdom of Hatra was still able to import distant Bactrian camels from the steppes of Central Asia and breed camels as a show of power.
Political power flex
Camels were likely considered to be a sacred animal to Allat, and other sculptures and friezes within the temple show the goddess riding the animals sidesaddle.