Donkeys have been used for centuries by humanity; pulling Mesopotamian war chariots or grinding grain during the Middle Ages. These animals have carried the heavy burden of civilization for many centuries.
When do we domesticate donkeys?
Now a new DNA study has revealed just how old the relationship between humans and domesticated donkeys ( Equus asinus ) really is.
“ The story of the donkey has baffled scientists for years,” says Ludovic Orlando, a molecular archaeologist at the Toulouse Center for Anthropobiology and Genomics in France. This discovery shows that donkeys were domesticated at one time, approximately 3,000 years before horses.
By comparing these genomes with those of wild asses, the researchers found that all donkeys could trace their lineage back to a single domestication event in East Africa, perhaps the Horn of Africa, around 5000 BC.
The researchers, led by Paul Sabatier University in Toulouse, France, have performed a comprehensive genetic analysis of modern and ancient donkeys, revealing their origins, expansion and management practices. By evaluating 238 modern and ancient donkey genomes (207 modern donkeys, 31 ancient donkeys, and 15 wild equids), the scientists found strong phylogeographic evidence supporting a single domestication event in East Africa more than 7,000 years ago.
“Donkeys subsequently spread to Eurasia from ~2500 BCE, with Central and East Asian subpopulations differentiated ~2000 to 1000 BCE,” the team wrote.
This event was followed by a series of expansions across Africa and Eurasia, where various subpopulations eventually became isolated and differentiated, most likely due to the aridity of the Sahara desert.
On the other hand, horses, their equine cousins, are thought to have been domesticated twice, the first time around 6,000 years ago on the steppes of western Eurasia.
Throughout history, donkey management involved interbreeding and the production of large stocks, particularly during a period when these creatures were essential to the Roman economy and military activities.
The authors suggest that the Romans bred improved strains of donkeys to produce mules that were essential to sustaining the military and economic might of the empire. Taken together, the genomic and archaeological evidence have the power to tell a comprehensive story of domestication: a story about donkeys that also tells about us.
“Donkeys are extraordinary working animals that are essential to the livelihoods of millions of people around the world,” say the experts who publish their work in the journal Science. “As humans, we owe a debt of gratitude to domestic donkeys for the role they play and have played in shaping society. Understanding humanity’s shared history with donkeys isn’t just about the past, it could actually be useful in the future .”
Referencia: E.T. Todd et al. The genomic history and global expansion of domestic donkeys. Science. Vol. 377, September 9, 2022, p. 1172. doi: 10.1126/science.abo3503.