BELFAST, Northern Ireland, April 4 (UPI) -- The crossing of the Alps and invasion of the Roman Empire by Hannibal and his army during the Second Punic War is considered by historians to be one of the greatest military campaigns in history, but until now, archaeologists couldn't say definitively where Hannibal and his troops crossed.
Human evidence of Hannibal's crossing has been hard to find, but new research has revealed traces of the animals that Hannibal and his army brought with them.
While excavating near a pond along a proposed passing called Col de Traversette, researchers from Queen's University Belfast discovered a "mass animal deposition" -- a layer of ancient excrement. The deposit was confirmed using a combination of microbial genetic analysis, environmental chemistry, pollen analysis and other tests.
Gene fragments sequenced from samples of the deposit suggest the excrement is dominated by microbes from the bacterial group Clostridia. For this reason, researchers believe the excrement was left by horses.
The pond next to the dig site is one of the only water sources on the route large enough to be shared by dozens of animals.
"The bacteria are very stable in soil, surviving for thousands of years," researchers Chris Allen, a microbiologist at Queen's University, wrote in The Conversation.
Carbon isotope analysis suggests the horse droppings were left around 200 B.C., close the the historical record of Hannibal's crossing in 218 B.C.
"The deposition lies within a churned-up mass from a 1-meter thick alluvial mire, produced by the constant movement of thousands of animals and humans," Allen said in a press release.
Researchers are hopeful that further genetic sequencing from the deposit can shed additional light on the historic crossing.
"We may also be able to find parasite eggs -- associated with gut tapeworms -- still preserved in the site like tiny genetic time capsules," Allen said. "With this information, we hope to to shed considerable light on the presence of horses, men -- and even Hannibal's famous elephants -- at the Traversette mire."
