Department of Anthropology, University of Arkansas, Fayetteville, AR, USA; Environmental Dynamics Program, University of Arkansas, Fayetteville, AR, USA.
Department of Anthropology, University of Arkansas, Fayetteville, AR, USA.
J Hum Evol. 2020 Mar;140:102315. doi: 10.1016/j.jhevol.2017.03.005. Epub 2017 May 9.
Reconstructions of habitat at sites like Kanapoi are key to understanding the environmental circumstances in which hominins evolved during the early Pliocene. While Australopithecus anamensis shows evidence of terrestrial bipedality traditionally associated with a more open setting, its enamel has low δC values consistent with consumption of C foods, which predominate in wooded areas of tropical Africa. Habitat proxies, ranging from paleosols and their carbonates to associated herbivore fauna and their carbon isotope ratios, suggest a heterogeneous setting with both grass and woody plant components, though the proportions of each have been difficult to pin down. Here we bring dental microwear texture analysis of herbivorous fauna to bear on the issue. We present texture data for fossil bovids, primates, rodents, and suids (n = 107 individuals in total) from the hominin bearing deposits at Kanapoi, and interpret these in the light of closely related extant mammals with known differences in diet. The Kanapoi bovid results, for example, are similar to those for extant variable grazers or graze-browse intermediate taxa. The Kanapoi suid data vary by taxon, with one similar to the pattern of extant grazers and the other more closely resembling mixed feeders. The Kanapoi primates and rodents are more difficult to associate with a specific environment, though it seems that grass was likely a component in the diets of both. All taxa evince microwear texture patterns consistent with a mosaic of discrete microhabitats or a heterogeneous setting including both tree and grass components.
对 Kanapoi 等遗址的栖息地重建，对于理解人类在早更新世期间的进化环境至关重要。虽然南方古猿源泉种表现出传统上与更开阔环境相关的陆地两足行走的证据，但它的牙釉质具有较低的 δC 值，这与在热带非洲的林地中占主导地位的 C 类食物的消耗一致。栖息地示踪剂，从古土壤及其碳酸盐到相关的食草动物群及其碳同位素比值，表明存在一个具有草本和木本植物成分的混合环境，尽管每种成分的比例一直难以确定。在这里，我们利用食草动物群的牙齿微观磨损纹理分析来解决这个问题。我们提供了来自 Kanapoi 含人类化石沉积物的化石牛科动物、灵长类动物、啮齿动物和猪科动物（总共 107 个个体）的纹理数据，并根据已知饮食差异的密切相关的现存哺乳动物来解释这些数据。例如，Kanapoi 牛科动物的结果与现存的多变食草动物或食草 - 杂食中间分类群相似。Kanapoi 猪科动物的数据因分类群而异，其中一种与现存的食草动物模式相似，另一种则更接近混合食者。Kanapoi 的灵长类动物和啮齿动物更难以与特定的环境相关联，尽管似乎草是它们饮食的一个组成部分。所有分类群都表现出与离散微生境的镶嵌或包括树木和草本植物成分的混合环境一致的微观磨损纹理模式。
