Morphological Approach to Genetic Variability of the Asiatic Wild Ass ( Equus hemionus ) Using Non-metric Skull Characters

Abstract

The Asiatic wild ass ( Equus hemionus ) is a globally endangered large mammal threatened by competition with livestock, poaching as well as habitat fragmentation and loss. Because of these environmental stresses it can be assumed that the species suff ers from lower developmental stability and that barrier eff ects could cause genetic isolation. To gain more insight into the population genetics of the Asiatic wild ass, a series of 440 skulls found in two Gobi regions of Mongolia were examined. The epigenetic variability and epigenetic distance between the samples as well as their fl uctuating asymmetry were studied by using 62 non-metric skull characters to test and evaluate possible genetic depletion, genetic isolation and the general infl uences during ontogenesis. The high epigenetic variability, I ev = 0.39 did not diff er between the two regions indicating no evidence of genetic depression. The very low, but signifi cant epigenetic divergence of MMD = 0.05 between the Dzungarian Gobi and the Southern Gobi suggests restricted connectivity. The moderate degree of fl uctuating asymmetry (FA = 0.11 – 0.15) found gives no signs of reduced developmental stability. Thus, our results suggest that Asiatic wild ass from Mongolia are from genetically viable populations.

Keywords

• Asiatic wild ass
• epigenetic variability
• Equus hemionus
• fl uctuating asymmetry
• non-metric skull characters
• population genetics
• Southern Mongolia