Percorrer por autor "Ward, Carol V."
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- The late pliocene to early pleistocene lomekwi faunas, west Turkana, Kenya: systematics, paleoecology, and biochronologyPublication . Geraads, Denis; Bobe, René; Ward, Carol V.; Plavcan, J. Michael; Manthi, Fredrick KyaloWe describe here the vertebrate fauna collected by the West Turkana Paleo Project at Lomekwi, a site best known for yielding the holotype of Kenyanthropus platyops and Lomekwian stone tools, and consisting of several collecting areas providing fossil samples ranging in age from about 3.6 to 2.2 Ma. Analysis of the newly recovered material, alongside a thorough revision of earlier collections, has led to the identification of 85 vertebrate taxa, which provide biochronological indications that help refine the site's chronology and shed light on the paleoenvironmental conditions prevailing during a critical period of early hominin diversification. The newly described fauna illustrates that during the time of Kenyanthropus, hominins shared their landscapes with a rich assemblage of vertebrates, including abundant megaherbivores, some 28 species of artiodactyls, diverse large and medium-size carnivores, and giant crocodiles as apex predators in the lakes and rivers of the Turkana region in the Pliocene. Among primates, the recurring association of Theropithecus with hominins is found at Lomekwi as it is elsewhere. Paleoenvironmental proxies from the Turkana region emphasize the complex and dynamic nature of the habitats that supported this rich biodiversity.
- Pliocene hominins from East Turkana were associated with mesic environments in a semiarid basinPublication . Villaseñor, Amelia; Uno, Kevin T.; Kinyanjui, Rahab N.; Behrensmeyer, Anna K.; Bobe, René; Advokaat, Eldert L.; Bamford, Marion; Carvalho, Susana; Hammond, Ashley S.; Palcu, Dan V.; Sier, Mark J.; Ward, Carol V.; Braun, David R.During the middle Pliocene (similar to 3.8-3.2 Ma), both Australopithecus afarensis and Kenyanthropus platyops are known from the Turkana Basin, but between 3.60 and 3.44 Ma, most hominin fossils are found on the west side of Lake Turkana. Here, we describe a new hominin locality (ET03-166/168, Area 129) from the east side of the lake, in the Lokochot Member of the Koobi Fora Formation (3.60-3.44 Ma). To reconstruct the paleoecology of the locality and its surroundings, we combine information from sedimentology, the relative abundance of associated mammalian fauna, phytoliths, and stable isotopes from plant wax biomarkers, pedogenic carbonates, and fossil tooth enamel. The combined evidence provides a detailed view of the local paleoenvironment occupied by these Pliocene hominins, where a biodiverse community of primates, including hominins, and other mammals inhabited humid, grassy woodlands in a fluvial floodplain setting. Between <3.596 and 3.44 Ma, increases in woody vegetation were, at times, associated with increases in arid-adapted grasses. This suggests that Pliocene vegetation included woody species that were resilient to periods of prolonged aridity, resembling vegetation structure in the Turkana Basin today, where arid-adapted woody plants are a significant component of the ecosystem. Pedogenic carbonates indicate more woody vegetation than other vegetation proxies, possibly due to differences in temporospatial scale and ecological biases in preservation that should be accounted for in future studies. These new hominin fossils and associated multiproxy paleoenvironmental indicators from a single locale through time suggest that early hominin species occupied a wide range of habitats, possibly including wetlands within semiarid landscapes. Local-scale paleoecological evidence from East Turkana supports regional evidence that middle Pliocene eastern Africa may have experienced large-scale, climate-driven periods of aridity. This information extends our understanding of hominin environments beyond the limits of simple wooded, grassy, or mosaic environmental descriptions. (c) 2023 Elsevier Ltd. All rights reserved.