New study on elephant energetics sheds light on Hannibal’s Alpine crossing route

In 218 BC during the Second Punic War, the Carthaginian general Hannibal led an army of 46,000 men and 7,000 horses through the Alps into Italy to invade the Romans. He also took with him 37 war elephants. Historians have disagreed for centuries on which route Hannibal was most likely to have taken. A new study co-authored by Pembroke Senior Associate Professor Fritz Vollrath and published in Proceedings of the National Academy of Sciences offers convincing evidence to help map the Carthaginian general’s famous Alpine crossing route. 

The study considered which of all the possible Alpine routes would have been the most energy efficient, especially for the army’s war elephants. Drawing on modelling methods based on the energy costs of movement of contemporary African elephants, which plan their journeys to save energy and find food more easily, the research team was able to estimate the energy costs of different possible Alpine crossings. Their findings suggest that the Col de la Traversette is the most likely route as opposed to Col du Clapier which was another strong contender. 

According to the study, the Col de la Traversette would have been the shortest and most energetically efficient route. Other possible routes through Col de Mongenèvre, Col du Clapier or Col du Mont Cenis would have required between 11-19% more energy for the army as a whole. 

These findings show how interdisciplinary research and analysing ancient sources in tandem with modern analytical methods in ecology can lead to new discoveries about historical events. Professor Fritz Vollrath shared: “Applying insights gained from studying the energetics of African elephants in Kenya is bringing a novel dimension to the longstanding debate over Hannibal’s Alpine crossing.” 

You can find the study ‘Energy costs of Hannibal’s alpine crossing’ in Proceeding of the National Academy of Sciences.