Tracking Hannibal with Ancient Horse Dung

Hard as history scholars and scientists have tried, they can’t seem to pinpoint the exact location where Hannibal famously crossed the Alps to invade Italy and defeat the Romans in 218 BC. Until now the path has remained largely illusive, however thanks to an unlikely source, researchers are maintaining that they’re closer than ever to finding the sweet spot.

Thanks to advanced modern science and samples of ancient horse waste, microbiologists are claiming that they’ve found what could be the path that the legendary leader of the Carthaginian army carved through the mountains. Forerunning around 15,000 men, 15,000 horses and 37 elephants, Hannibal’s feat crippled the Roman war machine and went down in history as one of the most impressive military achievements of all time. For over 2000 years historians have debated over his exact path, and finally bona fide archaeological evidence could offer closure.

Carbon dating 2000-year-old faeces

Fronted by Bill Mahaney of Toronto’s York University, an international team set their sights on the Col de Traversette pass bordering France and Italy. Using a blend of environmental chemistry, microbial genetic analysis, pollen testing and geophysical techniques, the team was able to source ancient faecal materials excreted by horses. Carbon isotope analysis dated the waste to around 200BC, which is remarkably close to the year Hannibal’s army traversed the mountains.

So how was the team able to determine where the faecal material came from? More than 70% of horse dung microbes belong to the Clostridia group, which meant that when microbiologists detected high counts in the samples, they knew they were excreted by the army’s mounts. As Clostridia bacteria thrive in soil, they were able to survive in the mountains for thousands of years.

Follow up research now underway

While the findings are an exciting discovery, Mahaney is stressing that they can’t be 100% certain until further analysis is carried out. This includes expanding the scope of gene analysis and assembling complete or partial Clostridia genomes using faecal samples from the supposed route.

As indicated by Mahaney and his team, science plays an integral role in helping us learn more about the past. For a glimpse at one of the most exciting and transformative laboratory techniques now being used by scientists worldwide, ‘Advances in Multi-mode Mass Spectrometry for Tissue Imaging Studies’ explores how the combination of matrix assisted laser desorption ionisation (MALDI) and MS is a powerful technique for the spatial localisation of a wide range of compounds.