Thursday, September 08, 2022

Donkey domestication occurred more than 7,000 years ago in Africa, genomic study finds


Peer-Reviewed Publication

AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE (AAAS)

A comprehensive genomic analysis of modern and ancient donkeys reveals the origins, expansion and management practices underlying the important pack animal’s domestication over thousands of years. Understanding the donkey’s largely overlooked genetic history is not only important in assessing their contribution to human history but could also improve their local management in the future. Domestic donkeys (Equus asinus) have been important to humans for thousands of years, providing a source of animal labor and long-distance transport for many cultures. However, despite their importance to ancient pastoral societies across Africa, Europe and Asia, little is known about their long history with humans, particularly regarding their origin, domestication and the impact of human management on their genomes. Although these creatures remain essential for developing low- and middle-income communities, particularly those in semi-arid and upland environments, they remain notably understudied, likely due to their currently undervalued status and loss of utility in modern industrialized societies, according to the authors. To address this gap, Evelyn Todd and colleagues evaluated 238 modern and ancient donkey genomes, discovering new insights into their domestication history. Todd et al. found strong phylogeographic evidence supporting a single domestication event in eastern Africa more than 7000 years ago (~5000 BCE). This was followed by a series of expansions throughout Africa and into Eurasia where subpopulations eventually became isolated and differentiated, perhaps due to the aridification of the Sahara. Eventually, genetic streams from Europe and the Near East found their way back into western African donkey populations. The analysis also uncovered a new genetic lineage from the Levant region that existed roughly 2200 years ago and contributed increasing gene flow toward Asian donkey populations. Todd et al. also revealed insights into donkey management, including breeding and husbandry, including evidence for selection for large size and significant inbreeding in ancient donkey populations.

No comments:

Post a Comment