Human beings have been credited with unparalleled capabilities for digital prehension grasping. However, grasping behaviour is widespread among tetrapods. The propensity to grasp, and the anatomical characteristics that underlie it, appear in all of the major groups of tetrapods with the possible exception of terrestrial turtles. Although some features are synapomorphic to the tetrapod clade, such as well-defined digits and digital musculature, other features, such as opposable digits and tendon configurations, appear to have evolved independently in many lineages. Here we examine the incidence, functional morphology, and evolution of grasping across four major tetrapod clades. Our review suggests that the ability to grasp with the manus and pes is considerably more widespread, and ecologically and evolutionarily important, than previously thought. The morphological bases and ecological factors that govern grasping abilities may differ among tetrapods, yet the selective forces shaping them are likely similar. We suggest that further investigation into grasping form and function within and among these clades may expose a greater role for grasping ability in the evolutionary success of many tetrapod lineages.

The emergence of lithic technology by ∼2.6 million years ago (Ma) is often interpreted as a correlate of increasingly recurrent hominin acquisition and consumption of animal remains. Associated faunal evidence, however, is poorly preserved prior to ∼1.8 Ma, limiting our understanding of early archaeological (Oldowan) hominin carnivory. Here, we detail three large well-preserved zooarchaeological assemblages from Kanjera South, Kenya. The assemblages date to ∼2.0 Ma, pre-dating all previously published archaeofaunas of appreciable size. At Kanjera, there is clear evidence that Oldowan hominins acquired and processed numerous, relatively complete, small ungulate carcasses. Moreover, they had at least occasional access to the fleshed remains of larger, wildebeest-sized animals. The overall record of hominin activities is consistent through the stratified sequence – spanning hundreds to thousands of years – and provides the earliest archaeological evidence of sustained hominin involvement with fleshed animal remains (i.e., persistent carnivory), a foraging adaptation central to many models of hominin evolution.

Abstract. Vultures comprise two geographically isolated and taxonomically distinct groups, Old World accipitrids and New World vulturids, and provide a classic case of convergent evolution. In both regions, several species of vultures often feed together in large numbers on carcasses. Behavioral studies of East African and Amazonian vultures have documented parallels in apparent ecological separation within this guild of specialized scavengers. Here morphological differences in skull, beak, and mandibular dimensions are compared among sympatric vultures in East Africa, South Africa, the Indian subcontinent, Amazonia, and the Pleistocene Rancho La Brea deposits in California. A discriminant function analysis based on morphological indices separates three basic feeding types: rippers, gulpers, and scrappers. Vultures of the three feeding types are present in both Pleistocene and Recent assemblages and show a similar distribution of body sizes into three size classes, suggesting that competition has favored similar pathways of ecological separation. This is true even when phylogenetic differences among some of the assemblages are partially accounted for. Comparisons between the fossil and extant New World vultures indicate that more specialized species were prone to extinction and that there has been a reduction in body size since the Pleistocene.

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One million to two million years ago, most of today's large, predatory mammals coexisted with larger extinct species, such as saber-toothed cats and giant running bears. Comparisons of tooth fracture frequencies from modern and Pleistocene carnivores imply that predator-prey dynamics and interspecific interactions must have been substantially different 36,000 to 10,000 years ago. Tooth fracture frequencies of four Rancho La Brea species-dire wolf, coyote, saber-toothed cat, and American lion-were about three times that of extant carnivores. Consequently, these findings suggest that these species utilized carcasses more fully and likely competed more intensely for food than presentday large carnivores.