Characterisation of the Genetic Diversity, Structure and Admixture of Dromedary Populations

The dromedary (Camelus dromedarius) commonly referred to as ‘ship of the desert’ has played an important part in the development and expansion of trading networks across inhospitable habitats over three millennia. Caravan roads were among the main exchange networks in human history and they likely facilitate livestock movements across large geographic distances. In particular dromedary camels are known to have been traded along these roads. The aim of this study was to use genetic markers to assess the population genetic diversity and structure of the Camelus dromedarius. Nine hundred and seventy animals from 20 countries representative the entire species geographic range were screened with 17 microsatellite loci. Our results support extensive dromedary camel movements along the trade routes contributing significantly to the current gene pools. More particular, weak genetic differentiation is observed across most of dromedary populations, likely the result of high gene flow along the trading routes. However, the Horn of Africa population appears to have been genetically isolated from the others populations, a possible consequence of its environmental and cultural distinctiveness limiting the amount of gene flow. The results foster our comprehension of the evolutionary history of C. dromedarius while providing an unique new window on the pattern and process of trading in ancient times.