Holocene footprints in Namibia: The influence of substrate on footprint variability

Researchers uncovered a Holocene-era footprint site in Namibia's Namib Sand Sea, revealing how substrate properties—grain size, moisture content, and sediment disturbance—significantly influence intratrail footprint variability. The study found that firm substrates produce shallow impressions reflecting peak plantar pressure, while softer ones yield deep prints with narrow heels and diminished medial longitudinal arches. Medium-bearing-capacity substrates create displacement rims, obscuring the true arch form. Using a 'whole foot' analytical technique, the team demonstrated that substrate conditions, not locomotor mechanics, primarily control footprint typology in consistent trails. This conceptual model offers critical insights for interpreting paleoanthropological sites, such as those in Ileret, Kenya, where substrate analysis could refine understanding of early human locomotion.

Morse, S. A., Bennett, M. R., Liutkus‐Pierce, C., Thackeray, F., McClymont, J., Savage, R., & Crompton, R. H. (2013). Holocene footprints in Namibia: The influence of substrate on footprint variability. American Journal of Physical Anthropology, 151(2), 265–279. Portico. https://doi.org/10.1002/ajpa.22276