Abstract The Mexican horse Equus conversidens is a representative member of the Quaternary North American megafauna. Systematics, phylogeny, and stable isotope ecology of this species are known in some detail, although information regarding population ecology is unexplored. Numerous fossil remains (isolated teeth, mandibles, skulls, and postcranial elements) of this horse have been collected from Pleistocene deposits that outcrop at southeastern Hidalgo, central Mexico. The available dental sample is suitable for recovering some aspects of its population dynamics. Our study compares life history traits of cohorts of E. conversidens from the state of Hidalgo to extant and Pleistocene species of equids from North America (United States and Canada), Europe (France), and Africa (Rwanda, Namibia). Life tables and age-structured models allow us to describe demographic parameters and mortality patterns. We highlight that E. conversidens was a typical K-strategists with high probability of surviving to adulthood with asymptotic growth rate (λ = 1.05) indicating a population close to balance. Considering the mammalian associations from different habitats in southeastern Hidalgo and the flexible diet of E. conversidens, we suggest that ambush (Panthera atrox) and cursorial predators (Canis dirus) played a major role in the prime-dominated mortality pattern of this species. The presence of a woodland-grassland ecosystem that sustained a high diversity of herbivores and the occurrence of large-sized predators suggest that the population dynamics were regulated by resource availability and selective predation, as it occurs in populations of the extant plains zebra, E. quagga.

中文翻译：

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伊达尔戈（墨西哥中部）晚更新世马科马科（Perissodactyla，Equidae）的种群动态：与现存和化石马科动物种群的比较

摘要 墨西哥马 Equus conversidens 是北美第四纪巨型动物群的代表成员。该物种的系统学、系统发育和稳定同位素生态学在某些细节上是已知的，尽管有关种群生态学的信息尚未探索。这匹马的许多化石遗骸（孤立的牙齿、下颌骨、头骨和颅后元素）是从墨西哥中部伊达尔戈东南部露头的更新世沉积物中收集到的。可用的牙科样本适用于恢复其种群动态的某些方面。我们的研究比较了来自伊达尔戈州的 E. conversidens 队列与来自北美（美国和加拿大）、欧洲（法国）和非洲（卢旺达、纳米比亚）的现存和更新世马科动物的生活史特征。生命表和年龄结构模型使我们能够描述人口统计参数和死亡率模式。我们强调，E. conversidens 是典型的 K 策略者，很有可能以渐近增长率 (λ = 1.05) 存活到成年，表明种群接近平衡。考虑到来自伊达尔戈东南部不同栖息地的哺乳动物协会以及 E. conversidens 的灵活饮食，我们建议伏击 (Panthera atrox) 和游动捕食者 (Canis dirus) 在该物种的主要死亡模式中发挥了重要作用。林地-草地生态系统的存在维持了高度多样性的食草动物和大型食肉动物的出现表明种群动态受到资源可用性和选择性捕食的调节，