July 28, 2010

Ancient DNA provides clues to donkey domestication

Proceedings of the Royal Society B doi: 10.1098/rspb.2010.0708

Ancient DNA from Nubian and Somali wild ass provides insights into donkey ancestry and domestication

Birgitta Kimura et al.

Genetic data from extant donkeys (Equus asinus) have revealed two distinct mitochondrial DNA haplogroups, suggestive of two separate domestication events in northeast Africa about 5000 years ago. Without distinct phylogeographic structure in domestic donkey haplogroups and with little information on the genetic makeup of the ancestral African wild ass, however, it has been difficult to identify wild ancestors and geographical origins for the domestic mitochondrial clades. Our analysis of ancient archaeological and historic museum samples provides the first genetic information on the historic Nubian wild ass (Equus africanus africanus), Somali wild ass (Equus africanus somaliensis) and ancient donkey. The results demonstrate that the Nubian wild ass was an ancestor of the first donkey haplogroup. In contrast, the Somali wild ass has considerable mitochondrial divergence from the Nubian wild ass and domestic donkeys. These findings resolve the long-standing issue of the role of the Nubian wild ass in the domestication of the donkey, but raise new questions regarding the second ancestor for the donkey. Our results illustrate the complexity of animal domestication, and have conservation implications for critically endangered Nubian and Somali wild ass.


1 comment:

AK said...

A common process in animal breeding is to bring in a male from another locale for cross-breeding with the herd. Obviously, this wouldn't show up in an mtDNA analysis.

For that matter, it's even possible that Onsager (Equus hemionus) jacks might have been used, also without showing up in an mtDNA analysis.