Department of Anthropology, University of Florida, Gainesville, FL 32605, USA.
Am J Phys Anthropol. 2013 Jul;151(3):356-71. doi: 10.1002/ajpa.22281.
Inference of feeding adaptation in extinct species is challenging, and reconstructions of the paleobiology of our ancestors have utilized an array of analytical approaches. Comparative anatomy and finite element analysis assist in bracketing the range of capabilities in taxa, while microwear and isotopic analyses give glimpses of individual behavior in the past. These myriad approaches have limitations, but each contributes incrementally toward the recognition of adaptation in the hominin fossil record. Microwear and stable isotope analysis together suggest that australopiths are not united by a single, increasingly specialized dietary adaptation. Their traditional (i.e., morphological) characterization as "nutcrackers" may only apply to a single taxon, Paranthropus robustus. These inferences can be rejected if interpretation of microwear and isotopic data can be shown to be misguided or altogether erroneous. Alternatively, if these sources of inference are valid, it merely indicates that there are phylogenetic and developmental constraints on morphology. Inherently, finite element analysis is limited in its ability to identify adaptation in paleobiological contexts. Its application to the hominin fossil record to date demonstrates only that under similar loading conditions, the form of the stress field in the australopith facial skeleton differs from that in living primates. This observation, by itself, does not reveal feeding adaptation. Ontogenetic studies indicate that functional and evolutionary adaptation need not be conceptually isolated phenomena. Such a perspective helps to inject consideration of mechanobiological principles of bone formation into paleontological inferences. Finite element analysis must employ such principles to become an effective research tool in this context.
推断已灭绝物种的摄食适应是具有挑战性的，对我们祖先古生物学的重建利用了一系列分析方法。比较解剖学和有限元分析有助于确定分类群的能力范围，而微观磨损和同位素分析则提供了过去个体行为的线索。这些方法有其局限性，但都为在人化石记录中识别适应提供了增量贡献。微观磨损和稳定同位素分析表明，南方古猿并不是由单一的、日益专门化的饮食适应所统一的。它们传统的（即形态学的）特征是“坚果破碎机”，可能仅适用于一个分类群，即粗壮南猿。如果可以证明对微观磨损和同位素数据的解释是有误导性的或完全错误的，那么这些推断可以被拒绝。或者，如果这些推断来源是有效的，那么这仅仅表明形态学受到了系统发育和发育的限制。有限元分析在识别古生物学背景下的适应方面的能力是有限的。迄今为止，它在人类化石记录中的应用仅表明，在相似的加载条件下，南方古猿面部骨骼中的应力场形式与现生灵长类动物不同。这一观察结果本身并不能揭示摄食适应。个体发生研究表明，功能和进化适应不必是概念上孤立的现象。这种观点有助于将骨形成的生物力学原理纳入古生物学推断。有限元分析必须采用这些原则，才能成为该背景下有效的研究工具。
