Data from: A combined mesowear analysis of Mexican Bison antiquus shows a generalist diet with geographical variation

Bison antiquus was one of the largest and most widely distributed megafaunal species during the Late Pleistocene in North America, giving rise to the modern plains bison in the middle Holocene. Despite the importance of the ancient bison, little is known about its feeding ecology. We employed a combination of extended mesowear, and mesowear III to infer the diet preference and habitat use of three Mexican samples of B. antiquus. Two northern samples from the Transmexican Volcanic Belt morphotectonic Province: La Piedad-Santa Ana and La Cinta-Portalitos, as well as one southern sample from the Sierra Madre del Sur morphotectonic province: Viko Vijin. We found that the northern Mexican samples were primarily non-strict grazers, while the southern sample displays a pattern consistent with mixer feeder habits. This suggests variability among the diets of these bison samples, caused by different paleoenvironments. This evidence complements the paleoenvironmental reconstructions in the studied localities; for the northern samples, open prairies composed of patches of woodland or shrubland and for the southern locality a fluvial floodplain with short-lived vegetation. In both scenarios, grasses (Poaceae) were non-dominant. The dietary habits of our samples of ancient bison in Mexico are the southernmost dietary inference for the species in North America and expand our knowledge of the dietary habits of Bison antiquus during the late Pleistocene.

古野牛（Bison antiquus）是北美晚更新世（Late Pleistocene）分布最广、体型最大的巨型动物物种（megafaunal species）之一，于中全新世（middle Holocene）演化出现代平原野牛。尽管该古野牛类群具有重要研究价值，学界对其取食生态学（feeding ecology）却知之甚少。本研究结合拓展牙齿磨耗法（extended mesowear）与牙齿磨耗III法（mesowear III），对3份墨西哥古野牛标本的食性偏好（diet preference）与生境利用模式（habitat use）进行推断。这3份标本分别采自：跨墨西哥火山带构造地貌省（Transmexican Volcanic Belt morphotectonic Province）的2份北部标本——拉皮埃德达-圣安娜（La Piedad-Santa Ana）与拉辛塔-波塔尔托斯（La Cinta-Portalitos），以及南马德雷山脉构造地貌省（Sierra Madre del Sur morphotectonic province）的1份南部标本——维科维金（Viko Vijin）。研究结果显示，北部墨西哥标本主要为非严格草食性动物，而南部标本则呈现出与混合食性相符的取食模式。这表明不同古环境造成了这批野牛标本的食性差异。本研究结果可为研究区域的古环境重建提供补充证据：北部标本对应的生境为散布林地或灌丛的开阔草原，南部标本对应的生境则为生长短期植被的河流泛滥平原。两类生境中，禾本科（Poaceae）植物均不占优势。本研究中墨西哥古野牛标本的取食习惯，是北美范围内该物种最南端的食性推断结果，拓展了我们对晚更新世古野牛取食习性的认知。