Abstract Mortality curves are a valuable tool to study taphonomy and to infer population structure in ancient communities; however, they rely on the precise determination of ontogenetic ages of individual animals, which is often uncertain for fragmentary and isolated fossil remains. In this paper, we develop a new protocol to construct mortality curves for fossil rhinocerotids using both tooth rows and isolated teeth, based on dental wear. We tested and calibrated this protocol using 29 skulls and 18 jaws of extant rhinoceroses (Diceros bicornis, Rhinoceros sondaicus, and R. unicornis). We then applied it to four extinct rhinocerotid species from the late early Miocene locality of Beon 1 of Montreal-du-Gers, SW France: the teleoceratines Brachypotherium brachypus and Prosantorhinus douvillei, the basal rhinocerotine Plesiaceratherium mirallesi, and the early elasmotheriine Hispanotherium beonense. Findings allow us to estimate population structures of these rhinocerotids, based on the percentage of juveniles, subadults and adults. The mortality curves of Beon 1 rhinocerotids reveal several major periods of vulnerability: birth, weaning, sexual maturity, and middle-late adulthood. When compared to extant populations (D. bicornis, Ceratotherium simum, and R. unicornis) and other ancient case studies (Miocene of USA, Pleistocene of Southeast Asia and France), mortality rate curves from Beon 1 are similar in early and late life; however, they lack the increased socially-driven mortality that is observed between 25 and 50% of the potential lifespan in some populations of D. bicornis and in the Miocene teleoceratine Teleoceras proterum. The population structures of Pr. douvillei, Pl. mirallesi, and H. beonense are close to those of extant populations of D. bicornis. In contrast, adult specimens of B. brachypus are overrepresented at Beon 1, similarly to Aphelops malacorhinus at Love Bone Bed (USA), probably due to taphonomical bias. It is important to note that considering isolated or associated teeth alone results in significant differences in mortality curves and population structures at Beon 1, hence both samples should be studied.

中文翻译：

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法国 Montréal-du-Gers 的 Béon 1 地区晚期早中新世犀牛科（哺乳动物，Perissodactyla）的死亡率曲线和种群结构

摘要 死亡率曲线是研究埋藏学和推断古代社区人口结构的重要工具；然而，它们依赖于对个体动物个体发育年龄的精确确定，对于零碎和孤立的化石遗骸，这通常是不确定的。在本文中，我们开发了一种新的协议，基于牙齿磨损，使用牙齿排和孤立牙齿构建化石犀牛的死亡率曲线。我们使用现存犀牛的 29 个头骨和 18 个颌骨（Diceros bicornis、Rhinoceros sondaicus 和 R. unicornis）测试和校准了该协议。然后，我们将其应用于法国西南部蒙特利尔杜热尔 Beon 1 的中新世晚期晚期的四种已灭绝的犀牛物种：长角角兽 Brachypotherium brachypus 和 Prosantorhinus douvillei，基底犀角 Plesiaceratherium mirallesi，和早期的 elasmotheriine Hispanotherium beonense。研究结果使我们能够根据幼年、亚成体和成体的百分比来估计这些犀牛的种群结构。Beon 1 犀牛的死亡率曲线揭示了几个主要的脆弱时期：出生、断奶、性成熟和成年中后期。与现存种群（D. bicornis、Ceratotherium simum 和 R. unicornis）和其他古代案例研究（美国中新世、东南亚更新世和法国）相比，Beon 1 的死亡率曲线在生命早期和晚期相似；然而，它们缺乏社会驱动的死亡率增加，这种死亡率在某些双角 D. bicornis 种群和中新世远角角角兽中观察到的潜在寿命的 25% 至 50% 之间。Pr的人口结构。杜维莱, PL. mirallesi 和 H. beonense 与 D. bicornis 的现存种群接近。相比之下，B. brachypus 的成年标本在 Beon 1 中的数量过多，类似于 Love Bone Bed（美国）的 Aphelops malacorhinus，可能是由于埋藏学的偏见。重要的是要注意，单独考虑孤立或相关的牙齿会导致 Beon 1 的死亡率曲线和人口结构存在显着差异，因此应研究两个样本。