Evolutionary Anthropology BSc (Hons)
Testing the ‘Efficieincy Hypothesis’ of hafted tool technology
Professor Lawrence Barham
Professor Robin Crompton
Humans are distinctive among primates for our dependency on technology to meet basic physiological needs and especially for the close integration of technology in many aspects of our social and personal lives. This entanglement of material culture with our biology and behaviour is well theorised (e.g. Hodder, 2012), but in the context of human evolution it needs much more empirical support. With this in mind, we aim to address one key technological transition that took place between 500,000 and 300,000 years ago in Africa and Eurasia – the development of hafting. Hafting is the process by which the utility of a tool is extended by attaching it to a handle or shaft. The invention of hafting is often cited for its impact on human cognitive and social evolution given the added demands it placed on capacities for planning, memory, patience and learning (Ambrose, 2010). The proposition of an intimate link between the invention of hafting and the evolution of complex language has gained much attention and interest. Others have speculated that hafting confers anatomical and physiological benefits on its users.
They make the seemingly logical association between increasing the force and precision that can be applied and a reduction in the energy needs to complete a task relative to a non-hafted equivalent (Barham, 2013). The assumption is that hafted tools require less muscular power to use and so demand less energy which in turn will have an impact on the evolution of the human body form. A reduction in skeletal robusticity seems to occur in humans after 300,000 years ago (Ruff et al., 1993), and may be a consequence of the invention and spread of hafting. This series of linked assumptions has been consolidated in the ‘Efficiency Hypothesis’ and although the rationale appears logical, if not obvious, it has not been tested. This PhD project will be the first systematic effort to test the hypothesis and will apply an interdisciplinary methodology that integrates experimental archaeology with research on the biomechanics of the human body.
Human evolution, Stone tool technology, Biological Anthropology