Stable isotopes reveal diet shift from pre-extinction to reintroduced Przewalski’s horses

The Przewalski’s horse (Equus ferus przewalskii), the only remaining wild horse within the equid family, is one of only a handful of species worldwide that went extinct in the wild, was saved by captive breeding, and has been successfully returned to the wild. However, concerns remain that after multiple generations in captivity the ecology of the Przewalski’s horse and / or the ecological conditions in its former range have changed in a way compromising the species' long term survival. We analyzed stable isotope chronologies from tail hair of pre-extinction and reintroduced Przewalski’s horses from the Dzungarian Gobi and detected a clear difference in the isotopic dietary composition. The direction of the dietary shift from being a mixed feeder in winter and a grazer in summer in the past, to a year-round grazer nowadays, is best explained by a release from human hunting pressure. A changed, positive societal attitude towards the species allows reintroduced Przewalski’s horses to util...普氏野马（Przewalski’s horse，*Equus ferus przewalskii*）是马科现存唯一的野生马类，亦是全球少数几类曾在野外灭绝、经人工圈养繁育成功后得以重新野化回归的物种之一。然而目前仍存在潜在隐忧：经多代圈养后，普氏野马的生态习性及其原分布区域的生态环境或已发生改变，进而威胁该物种的长期生存。本研究对准噶尔戈壁（Dzungarian Gobi）灭绝前种群与重新引入种群的尾毛稳定同位素年代序列展开分析，结果显示二者的同位素饮食组成存在显著差异。该物种饮食结构的转变方向，从过去冬季为混合取食者、夏季为草食者，变为如今的全年纯草食者，这一变化最合理的解释为人类狩猎压力的解除。而社会对该物种态度的积极转变，使得重新引入的普氏野马得以利用...