Domestication of the donkey might have been slower and less linear than previously thought, according to an international group of researchers.
Washington, March 11 : Domestication of the donkey might have been slower and less linear than previously thought, according to an international group of researchers.
Collaborators from Washington University in St. Louis and the University of Copenhagen studied 10 donkey skeletons from three graves dedicated to donkeys in the funerary complex of one of the first Pharaoh's at Abydos, Egypt.
The researchers found that donkeys around 5,000 years ago were in an early phase of domestication, and that they looked like wild animals but displayed joint wear that showed that they were used as domestic animals.
"Genetic research has suggested African origins for the donkey. But coming up with an exact time and location for domestication is difficult because signs of early domestication can be hard to see. Our findings show that traces of human management can indicate domestication before skeletal or even genetic changes," said Fiona Marshall, professor of Anthropology at Washington University in St. Louis.
In their study report, published in the online edition of the Proceedings of the National Academy of Sciences, the researchers write that domestication of the donkey from the African wild ass was a pivotal point in human history because it transformed ancient transport systems in Africa and Asia, and the organization of early cities and pastoral societies.
During the study, the researchers examined the 5,000-year-old Abydos skeletons along with 53 modern donkey and African wild ass skeletons.
They observed that the Abydos metacarpals were similar in overall proportions to wild ass, but their individual measurements varied.
While mid-shaft breadths of the domestic donkey resembled wild ass, mid-shaft depths and distal breadths were intermediate between the two species.
However, the researchers also observed that all the Abydos skeletons exhibited a range of wear and other pathologies on their bones consistent with load carrying.
The authors of the study write that morphological similarities to wild ass suggest that despite their use as beasts of burden, donkeys were still undergoing considerable phenotypic change during the early dynastic period in Egypt.
According to them, this pattern is consistent with recent studies of other domestic animals that suggest that the process of domestication is slower and more complicated than had been previously thought.
ANI