Holocene vegetation dynamics of the Koobi Fora Basin, East Turkana, Kenya: Insights from phytolith analysis

A progressive shift from wooded grasslands to open shrublands over the Holocene in the Koobi Fora Basin, East Turkana, reflects increasing aridity and likely anthropogenic influence. Phytolith analysis of 23 sediment samples—twenty from the Holocene Galana Boi Formation and three modern—reveals subtle but significant vegetation changes: early Holocene wooded grasslands gave way to open wooded grasslands by the mid-Holocene, culminating in today's sparsely vegetated shrublands. Intra-site variations at Karari Ridge suggest localized human modification, with elevated palm phytoliths indicating resource use. These ecological shifts align with basin-wide paleoclimate data and coincide with socio-economic transitions from hunter-gatherer-fisher lifestyles to early pastoralism (∼5000 years ago), which adapted to arid conditions by integrating livestock with wild food resources. The study underscores the resilience of pastoralist systems in response to environmental pressures, though it calls for expanded sampling and multiproxy approaches to deepen understanding of human-environment interactions.

Kinyanjui, R. N., Mashaka, H. K., Chritz, K. L., Wemanya, S. N., Ndiema, E. K., Braun, D. R., & Bamford, M. (2026). Holocene vegetation dynamics of the Koobi Fora Basin, East Turkana, Kenya: Insights from phytolith analysis. Quaternary International, 759, 110131. https://doi.org/10.1016/j.quaint.2026.110131