PRESERVING THE IMPOSSIBLE: METHODS FOR THE CONSERVATION OF SOFT-SEDIMENT HOMININ FOOTPRINT SITES

Human and hominin footprints within the geological record provide critical evidence for presence as well as information on the biomechanics of the individuals who made those prints. In addition, the animal prints present at such site provide insight into the faunal communities and paleo-environments. Such sites are comparatively rare within the geological record but are of great importance. Unlike most dinosaur footprint sites they are commonly occur in soft, near-surface sediments offering a particular challenge with respect to conservation and preservation. Bennett et al. (2009; Science, 323) recently described a series of 1.5 million year old footprints from northern Kenya preserved in fine-grained mud. These prints provide new insight into the evolution of human gait and are the second oldest footprints in the World after those at Laetoli in Tanzania. The challenge of conserving this new footprint site forms the focus for this paper. In the field, optical laser scanning was used to capture the footprint surfaces both for analysis as well providing the basis for producing footprint replicas via three-dimensional printing technology for museum display. This does not however solve the issue of in situ preservation which remains challenging, yet important to the local community in terms of potential tourism. A range of possible conservation strategies are explored and their implications for different stake holders considered. While there are no easy solutions to the challenge of preserving sites of this sort, we suggest a range of possible ways forward which are also more generally applicable to the problem of preserving fragile soft-sediment environments for future generations.