Dating early hominids

The diet of the earliest hominins was probably somewhat similar to the diet of modern chimpanzees: omnivorous, including large quantities of fruit, leaves, flowers, bark, insects and meat (e.g., Andrews & Martin 1991; Milton 1999; Watts 2008).

Tooth morphology and dental microwear studies suggest that the diet of some hominins may have included hard food items such as seeds and nuts, and underground storage organs (USOs) such as roots and tubers (Jolly 1970; Peters & O'Brien 1981; Teaford & Ungar 2000; Luca et al. By at least 2.6 million years ago, a remarkable expansion in this diet started to occur; some hominins began incorporating meat and marrow from small to very large animals into their diet. Inferring hominid and carnivore behavior from dual-patterned archaeofaunal assemblages.

dating early hominids-3

Slicing meat off a bone with a sharp-edged tool can leave cut marks (Figure 1).

Pounding a bone with a large stone to break it open and extract the marrow inside can leave percussion marks. Fact and fiction about the Zinajnthropus floor: data, arguments, and interpretations.

Cut and percussion marks, which together are called butchery marks, may be the result of skinning, disarticulation, and bone breakage for dietary and non-dietary reasons (Blumenschine & Pobiner 2006).

Scientists began to recognize these butchery marks on Early Stone Age fossil assemblages in the 1980s (e.g., Bunn 1981; Potts & Shipman 1981; Blumenschine & Selvaggio 1988). Hunting and scavenging by Plio-Pleistocene hominids: nutritional constraints, archaeological patterns and behavioural implications.

Experimental and prehistoric evidence for human chewing on bones has only recently begun to be explored (e.g., Landt 2007; Delaney-Rivera et al. Journal of Archaeological Science 20, 365-398 (1993).

2009; Fernandez-Jalvo and Andrews 2011; Pickering et al. Only those fossilized bones with butchery marks can confidently be tied to hominin diet (Blumenschine & Pobiner 2006). The earliest well-accepted evidence for this novel dietary behavior comes from about 2.6 Ma at the site of Gona, Ethiopia (Domínguez-Rodrigo et al. Probably not coincidentally, it's also around this time that we start to see the first evidence of archaeologically visible accumulations of stone tools (Semaw et al. There may be evidence of hominin-butchered bones at 3.4 Ma at Dikika, Ethiopia (Mc Pherron et al. 2010), where Australopithecus afarensis remains have been found, but this evidence consists of only a few bone specimens and has been disputed (Domínguez-Rodrigo et al. The earliest well documented evidence of persistent hominin carnivory from in situ excavated fossil fauna occurring in association with large concentrations of stone tools is at about 2.0 Ma at Kanjera, Kenya (Ferraro et al. In addition to terrestrial animals, evidence from one site at Koobi Fora shows that hominins began to incorporate aquatic foods like turtles, crocodiles, and fish into their diets by about 1.95 Ma (Braun et al. Multiple localities at Olduvai Gorge, Tanzania, dating to 1.8 Ma also show evidence of in situ butchered mammal remains, ranging in size from hedgehogs to elephants; these are also associated with large numbers of stone tools (Domínguez-Rodrigo et al. A taphonomic perspective on the archaeology of human origins. 2007; Blumenschine & Pobiner 2006 and references therein). Three sites at Koobi Fora, Kenya, preserve evidence of several butchered mammals from about 1.5 Ma but are not found in association with any stone tools (Pobiner et al. Perhaps this signals a shift toward intentional specialization of activities, such as animal butchery and stone tool making, in different areas across the landscape. Patterns of skeletal representation and hominid subsistence activities at Olduvai Gorge, Tanzania and Koobi Fora, Kenya. Currently, there is fossil evidence for at least three species of hominins occurring at around 2.6-2.5 Ma: Australopithecus africanus, Australopithecus garhi, and Paranthropus aethiopicus; H.