Part of SRSU Assistant Professor’s research was featured on the cover of “Science” magazine

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Donkeys are generally stubborn and not particularly fast animals.
But new research published in the Sept. 9 issue of the journal Science reveals that donkeys spread like wildfire from Africa some 4,500 years ago, reaching Europe and Asia within just a few centuries. increase.
This shows the important role donkeys played in past human societies. Especially as beasts of burden to mobilize people, cultures and goods across arid deserts and rugged mountains.
Amazingly, where and when the donkey was first domesticated has long remained a scientific mystery. Archaeological finds, texts, and iconographic evidence suggest large areas of northeastern Africa as possible sources.
However, they also referred to regions outside of Africa, perhaps the Arabian Peninsula, or even further afield, Mesopotamia.
Previous studies aimed at tracking the evolutionary history of donkeys using genetics failed to find significant support for candidate regions.
“We decided to sequence the genome of a donkey from a hitherto overlooked area,” said CNRS research director at the Center for Human Biology and Genomics in Toulouse (CNRS / Paul Sabatier, University of Toulouse III). said Ludovic Orlando, senior author of the study. in a press release. “This was hoped to reveal a key missing piece of the puzzle.”
This provided a research team of 49 scientists from 37 laboratories around the world with the most extensive panel of donkey genomes. However, mapping the genetic diversity of donkeys today may not be enough, as modern breeding and trade may have traded animals in very distant regions. , we also need to use the cutting edge of ancient DNA research to characterize the genomes of past-living donkeys.
Dr. Laura Patterson Rosa, Assistant Professor of Animal and Equine Sciences at Saarros State University, was part of the team that analyzed the donkey genome as part of the study.
Dr. Patterson Rosa’s efforts include the Pega, a unique South American donkey breed, handpicked for its smooth locomotion – a “walking” donkey breed – and endurance since the colonization of the Americas. A donkey sampling was included. Global and historical comparative genomic analyzes have shown that historical descriptions of the origin of this breed may not be entirely accurate. It raised concerns as conservation may require deliberate outbreeding to maintain health and population diversity.
“Modern donkeys in different parts of the world show very strong genetic differences, especially between the continents of Africa, Europe and Asia,” said lead author Evelyn Todd, PhD, in a press release. said in
In addition to marked geographic differences, the team found that the timing of isolation between different populations followed clear trends. It first started in Africa and spread to Eurasia and Asia. Researchers report that it originated in Africa about 7,000 years ago. This is roughly the time when the once lush Sahara region became one of the driest deserts on earth. They estimate that donkeys spread out of Africa at least 4,500 years ago and rapidly spread eastward into Asia and westward into Europe within up to 1,000 years.
The expansion is not only in one direction, but also back in Africa. Studies have shown, for example, that donkeys were already being traded between Europe and Africa across the Mediterranean by Roman times. These exchanges were two-way, and although they continued after the fall of the Roman Empire, they left the most important genetic imprint on modern donkeys in West Africa.
The ancient genome provided a safely mapped point in time and helped researchers track the spread of donkeys around the world. I made it One such lineage was discovered in the Levant about 2,000 years ago, but as researchers were able to identify traces of its genetic heritage in modern donkeys throughout Eastern Europe, Central Asia and East Asia, It probably inhabited a much wider geographical area.
The researchers also found that wild relatives of donkeys also donate some of their genes to different parts of the world.
“This may reflect free-range donkey populations in some parts of Africa and the Arabian Peninsula,” said Evelyn Todd.
Clearly, this study reveals important differences between the donkey and its close relative, the horse. In contrast to horses, donkey inbreeding has not increased significantly in modern times. This suggests similar reproductive strategies in the present and in the past.
But the researchers didn’t just track global patterns in donkey management techniques. They found a mule breeding center at Boingville-en-Woevre, a Roman site in northern France dating from the 2nd to his 5th century. There, at a time when mules provided the labor force to carry military equipment and supplies across empires spanning thousands of kilometers, breeders seem to have produced particularly inbred strains of giant donkeys. By crossing these giant donkeys with horse females, breeders were able to produce very valuable sterile mules.
Here, the genetic evidence echoes texts of Roman writers who stated that selective breeding of animals of exceptional stature was already common practice and lucrative business at the time.
“This is the beauty of ancient DNA that provides data that allows us to test hypotheses from other classical historical sources,” Orlando concluded.
Genetic research went one step further. The limited presence of horses at Boenville en Woevre suggests either female horses brought in for mating, or donkey breeders who visited the surrounding farms with giant males. A different kind of journey, certainly more limited in area than what brought their ancestors out of Africa thousands of years ago, but nonetheless contributed to the building of the mighty Roman Empire. Did.
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