Two species of papionins which are found in the Awash region only, primarily at 4.4 million year strata in Aramis , that have been classified Kuseracolobus aramisi and Pliopapio alemui (Frost, 2001), are ubiquitous in the assemblage, accounting for 30% of the larger mammals. (White, T. D., 2009) Since 40% of the mammals at Woranso-Mille (3.5 million years ago) are Theropithecus darti (Haile-Selassie et al., 2007), closely related to extant Gelada which is the only living Theropithecus, it seems probable that the Aramis papionins and the Woranso-Mille papionins, both the most abundant population amongst the mammals in the region at their time, are the same evolutionary lineage at 4.4 Ma and 3.5 Ma respectively. That trend of evolutionary lineages along a south-west to north-east direction, from Asa koma to Aramis to Hadar, can be observed for other species such as the Australopithecus lineage, the Hipparion lineage, the Kolpechoerus lineage, and the Kobus lineage (Nygren, J., 2018), following the counter-clockwise rotation of the Danakil block (Kidane, T., 2015), those species inhabiting coastal grasslands on Danakil, where the coast itself has been deposited into the Sea of Afar throughout the rotation of the Danakil block.
Synapses
FROST, S. R. (2001). New Early Pliocene Cercopithecidae (Mammalia: Primates) from Aramis, Middle Awash Valley, Ethiopia. American Museum Novitates, 3350, 1–36. https://doi.org/10.1206/0003-0082(2001)350<0001:nepcmp>2.0.co;2
White, T. D., Ambrose, S. H., Suwa, G., Su, D. F., DeGusta, D., Bernor, R. L., … Vrba, E. (2009). Macrovertebrate Paleontology and the Pliocene Habitat of Ardipithecus ramidus. Science, 326(5949), 67–67, 87–93. https://doi.org/10.1126/science.1175822
HAILE-SELASSIE, Y., DEINO, A., SAYLOR, B., UMER, M., & LATIMER, B. (2007). Preliminary geology and paleontology of new hominid-bearing Pliocene localities in the central Afar region of Ethiopia. Anthropological Science, 115(3), 215–222. https://doi.org/10.1537/ase.070426
Nygren, J. (2018). On the Origin of the Species, Danakil as the Galapagos of Pliocene East Africa. https://gist.github.com/resilience-me/1ee3b88c977ec5f8f46e08ffe42fd92a
Kidane, T. (2015). Strong clockwise block rotation of the Ali-Sabieh/Aïsha Block: evidence for opening of the Afar Depression by a “saloon-door” mechanism. Geological Society, London, Special Publications, 420(1), 209–219. https://doi.org/10.1144/sp420.10