Grit and consequence

Grit is implicated in several biological phenomena—it wears teeth, it fractures teeth, it drives tooth evolution, it elicits complex manual manipulations—any one of which could be described as a central topic in evolutionary anthropology. But what is grit? We hardly know because we tend to privilege the consequences of grit (it is abrasive) over its formal features, all but ignoring crucial variables such as mineral composition, material properties, and particle geometry (size, angularity), not to mention natural variation in the habitats of primates and their food surfaces. Few topics have animated so much debate and invited such cool indifference at the same time. Our goal here is to shine a light on grit, to put a philosophical lens on the nature of our discourse, and to call attention to large empirical voids that should be filled and folded into our understanding of primate natural history and evolution. Methods Raw data collected for figure 1c. See methods text of paper for more information.砂砾（grit）与多种生物学现象密切相关——它可磨损牙齿、造成牙折、推动牙齿演化，还能诱发复杂的手部操作行为，上述任一现象均可被视作进化人类学（evolutionary anthropology）的核心研究议题。但究竟何为砂砾？我们对此认知匮乏，盖因我们往往更重视砂砾的作用后果（即其磨蚀性），而非其形式特征，几乎完全忽略了矿物组成、材料属性、颗粒几何形态（尺寸、棱角度）等关键变量，更遑论灵长类栖息地及其食物表面的自然变异。鲜有议题能如砂砾这般，既引发诸多学术争论，又长期遭受冷遇。本文旨在聚焦砂砾这一研究对象，以哲学视角审视相关讨论的本质，并呼吁学界关注亟待填补的实证空白——这些空白理应被纳入我们对灵长类自然历史与演化的认知体系之中。 方法 用于生成图1c的原始数据。更多细节请参见论文的方法部分。