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Villaseñor A, Uno KT, Kinyanjui RN, Behrensmeyer AK, Bobe R, Advokaat EL, Bamford M, Carvalho SC, Hammond AS, Palcu DV, Sier MJ, Ward CV, Braun DR. Pliocene hominins from East Turkana were associated with mesic environments in a semiarid basin. J Hum Evol 2023; 180:103385. [PMID: 37229946 DOI: 10.1016/j.jhevol.2023.103385] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 04/15/2023] [Accepted: 04/19/2023] [Indexed: 05/27/2023]
Abstract
During the middle Pliocene (∼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.
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Affiliation(s)
- Amelia Villaseñor
- Department of Anthropology, The University of Arkansas, 330 Old Main, Fayetteville, AR, 72701, USA.
| | - Kevin T Uno
- Lamont-Doherty Earth Observatory of Columbia University, Division of Biology and Paleo Environment, Palisades, NY, 10964, USA
| | - Rahab N Kinyanjui
- Department of Earth Sciences, National Museums of Kenya, Nairobi, 40658-00100, Kenya; Department of Archaeology, Max Planck Institute of Geoanthropology, 07745, Jena, Germany; Human Origins Program, National Museum of Natural History, Smithsonian Institution, MRC 121, Washington, DC, 20013, USA
| | - Anna K Behrensmeyer
- Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, MRC 121, Washington, DC, 20013, USA
| | - René Bobe
- Primate Models for Behavioural Evolution Lab, Institute of Human Sciences, University of Oxford, 64 Banbury Road, Oxford, OX2 6PN, UK; Gorongosa National Park, Sofala, Mozambique
| | - Eldert L Advokaat
- Department of Earth Sciences, Utrecht University, Princetonlaan 8A, 3584 CB Utrecht, the Netherlands
| | - Marion Bamford
- Evolutionary Studies Institute and School of Geosciences, University of the Witwatersrand, P Bag 3, WITS, 2050, South Africa
| | - Susana C Carvalho
- Primate Models for Behavioural Evolution Lab, Institute of Human Sciences, University of Oxford, 64 Banbury Road, Oxford, OX2 6PN, UK; Gorongosa National Park, Sofala, Mozambique; Interdisciplinary Center for Archaeology and Evolution of Human Behaviour (ICArEHB), Universidade do Algarve, 8005-139, Faro, Portugal
| | - Ashley S Hammond
- Division of Anthropology, American Museum of Natural History (AMNH), New York, NY, 10024, USA; New York Consortium in Evolutionary Primatology at AMNH, New York, NY, 10024, USA
| | - Dan V Palcu
- Oceanographic Institute of the University of São Paulo, Brazil; Paleomagnetic Laboratory 'Fort Hoofddijk', Utrecht University, Budapestlaan 17, 3584 CD, Utrecht, the Netherlands
| | - Mark J Sier
- Centro Nacional de Investigación Sobre la Evolución Humana (CENIEH), Paseo Sierra de Atapuerca 3, 09002, Burgos, Spain; Department of Earth Sciences, University of Oxford, South Parks Road, OX1 3AN, Oxford, UK; Department of Earth Sciences, Utrecht University, Princetonlaan 8A, 3584 CB Utrecht, the Netherlands
| | - Carol V Ward
- Department of Pathology and Anatomical Sciences, University of Missouri, Columbia, MO, USA
| | - David R Braun
- Center for the Advanced Study of Human Paleobiology, Anthropology Department, George Washington University, Washington, DC, USA
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Negash EW, Barr WA. Relative abundance of grazing and browsing herbivores is not a direct reflection of vegetation structure: Implications for hominin paleoenvironmental reconstruction. J Hum Evol 2023; 177:103328. [PMID: 36857987 DOI: 10.1016/j.jhevol.2023.103328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 01/23/2023] [Accepted: 01/23/2023] [Indexed: 03/03/2023]
Abstract
The diet of fossil herbivores inferred from enamel stable carbon isotopes is often used to make paleoenvironmental reconstructions. While many studies have focused on using environmental indicator taxa to make paleoenvironmental reconstructions, community-based approaches are considered to provide a more complete picture of paleolandscapes. These studies assume that the diet and relative abundance of herbivores are related to the areal extent of different vegetation types on the landscape. Here, we quantitatively test this assumption in 16 modern ecosystems in eastern and southern Africa with a wide range of woody vegetation cover. We conducted a landscape-level spatial analysis of vegetation patterns using a published land cover data set and computed landscape metrics. We compiled data on relative abundance and diet of herbivores inferred from carbon isotope studies for all large herbivores in these ecosystems. We found that despite differences in the total areal extent of different vegetation types, numerous sizable patches of each vegetation type are available in most ecosystems. However, despite variation across the ecosystems examined, grazers are typically the most abundant herbivores even in sites that have a higher proportion of forest and shrub cover. This indicates that the diet and relative abundance of herbivores is not a simple reflection of the total areal extent of vegetation types available on the landscape. The higher proportion of grazers observed in these ecosystems is a result of multiple factors including habitat heterogeneity, differences in biomass turnover rate between grasses and woody vegetation, resource partitioning, and the advantages of group living in open environments. Comparison of diet and relative abundance of herbivores in modern ecosystems to fossil herbivore assemblages shows that very different vegetation regimes can support similar herbivore assemblages. This study has significant implications for paleolandscape reconstructions and cautions against a simplistic wooded vs. grassland paleoenvironmental interpretations based on fossil herbivore assemblages.
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Affiliation(s)
- Enquye W Negash
- Center for the Advanced Study of Human Paleobiology, George Washington University, 800 22nd Street, Northwest, Washington D.C. 20052, USA.
| | - W Andrew Barr
- Center for the Advanced Study of Human Paleobiology, George Washington University, 800 22nd Street, Northwest, Washington D.C. 20052, USA
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A nonanalog Pliocene ungulate community at Laetoli with implications for the paleoecology of Australopithecus afarensis. J Hum Evol 2022; 167:103182. [DOI: 10.1016/j.jhevol.2022.103182] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 02/28/2022] [Accepted: 03/02/2022] [Indexed: 11/17/2022]
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Hunt KD, Dunevant SE, Yohler RM, Carlson KJ. Femoral Bicondylar Angles among Dry-Habitat Chimpanzees ( Pan troglodytes schweinfurthii) Resemble Those of Humans: Implications for Knee Function, Australopith Sexual Dimorphism, and the Evolution of Bipedalism. JOURNAL OF ANTHROPOLOGICAL RESEARCH 2021. [DOI: 10.1086/715398] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Dumouchel L, Bobe R, Wynn JG, Barr WA. The environments of Australopithecus anamensis at Allia Bay, Kenya: A multiproxy analysis of early Pliocene Bovidae. J Hum Evol 2021; 151:102928. [PMID: 33453510 DOI: 10.1016/j.jhevol.2020.102928] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 12/01/2020] [Accepted: 12/01/2020] [Indexed: 11/18/2022]
Abstract
Australopithecus anamensis, among the earliest fully bipedal hominin species, lived in eastern Africa around 4 Ma. Much of what is currently known about the paleoecology of A. anamensis comes from the type locality, Kanapoi, Kenya. Here, we extend knowledge of the range of environments occupied by A. anamensis by presenting the first multiproxy paleoecological analysis focusing on Bovidae excavated from another important locality where A. anamensis was recovered, locality 261-1 (ca. 3.97 Ma) at Allia Bay, East Turkana, Kenya. Paleoenvironments are reconstructed using astragalar ecomorphology, mesowear, hypsodonty index, and oxygen and carbon isotopes from dental enamel. We compare our results to those obtained from Kanapoi. Our results show that the bovid community composition is similar between the two fossil assemblages. Allia Bay and Kanapoi bovid astragalar ecomorphology spans the spectrum of modern morphologies indicative of grassland, woodland, and even forest-adapted forms. Dietary reconstructions based on stable isotopes, mesowear, and hypsodonty reveal that these bovids' diet encompassed the full C3 to C4 dietary spectrum and overlap in the two data sets. Our results allow us to confidently extend our reconstructions of the paleoenvironments of A. anamensis at Kanapoi to Allia Bay, where this pivotal hominin species is associated with heterogeneous settings including habitats with varying degrees of tree cover, including grasslands, bushlands, and woodlands.
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Affiliation(s)
- Laurence Dumouchel
- Department of Anthropology, Wichita State University, 1845 Fairmount Street, Wichita, KS 67260, USA.
| | - René Bobe
- Primate Models for Behavioural Evolution Lab, Institute of Cognitive & Evolutionary Anthropology, School of Anthropology, University of Oxford, 64 Banbury Rd, Park Town, Oxford, OX2 6PN, UK; Paleo-Primate Project Gorongosa, Gorongosa National Park, Sofala, Mozambique; Interdisciplinary Center for Archaeology and Evolution of Human Behaviour (ICArEHB), Universidade Do Algarve, Campus de Penha, Faro, 8005-139, Portugal
| | - Jonathan G Wynn
- Division of Earth Sciences, National Science Foundation, 2415 Eisenhower Avenue, Alexandria, VA 22314, USA
| | - W Andrew Barr
- Center for the Advanced Study of Human Paleobiology, The George Washington University, 800 22(nd)Street Northwest, Suite 6000, Washington, DC 20052, USA
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Villaseñor A, Bobe R, Behrensmeyer AK. Middle Pliocene hominin distribution patterns in Eastern Africa. J Hum Evol 2020; 147:102856. [DOI: 10.1016/j.jhevol.2020.102856] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 06/30/2020] [Accepted: 06/30/2020] [Indexed: 11/28/2022]
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Barr WA, Biernat M. Mammal functional diversity and habitat heterogeneity: Implications for hominin habitat reconstruction. J Hum Evol 2020; 146:102853. [PMID: 32755690 DOI: 10.1016/j.jhevol.2020.102853] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 06/29/2020] [Accepted: 06/29/2020] [Indexed: 10/23/2022]
Abstract
Hominin habitats are frequently described as 'mosaic' based on interpretations of fossil assemblages comprising taxa with divergent functional adaptations (e.g., both grazers and browsers). This interpretation rests on an assumption that mammal functional diversity is positively associated with habitat heterogeneity. We test this assumption using modern mammal data for 141 sites in Africa. Species average body mass and locomotor and dietary information was compiled for all species >500 g. The functional diversity of each species assemblage was measured using five metrics: locomotor richness, trophic richness, functional richness, functional divergence, and functional evenness. We used a high-resolution woody cover estimate for sub-Saharan Africa to compute the coefficient of variation of percentage of woody cover for each site. We used a published land cover classification to compute the number of habitat patches and the number of distinct habitat types at each site. Multiple regressions were conducted at 9 different spatial resolutions (pixel size ranging from 100 m to 30 km) to explore the relationship between functional diversity and habitat heterogeneity metrics. The overall number of species found at a site is strongly positively associated with functional richness, locomotor richness, and trophic richness at all spatial resolutions. The number of habitat types at a site and the density of habitat patches show a modest positive relationship with most functional diversity metrics at most spatial resolutions. The coefficient of variation in woody cover is a very poor predictor of functional diversity. The locomotor and trophic richness of mammal communities are positively associated with habitat heterogeneity and may be useful for reconstructing aspects of heterogeneity at hominin sites. However, the overall number of species is an important confounding variable, which in turn depends on the sample size of the overall fossil sample. Researchers should carefully consider impacts of sample size on faunal reconstructions of habitat heterogeneity.
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Affiliation(s)
- W Andrew Barr
- Center for Advanced Study of Human Paleobiology, Department of Anthropology, The George Washington University, USA.
| | - Maryse Biernat
- Institute of Human Origins, School of Human Evolution and Social Change, Arizona State University, USA
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Du A, Alemseged Z. Diversity analysis of Plio-Pleistocene large mammal communities in the Omo-Turkana Basin, eastern Africa. J Hum Evol 2018; 124:25-39. [PMID: 30153945 DOI: 10.1016/j.jhevol.2018.07.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 07/13/2018] [Accepted: 07/16/2018] [Indexed: 11/19/2022]
Abstract
Knowing how the diversity of large mammal communities changes across space and time provides an important ecological framework for studying hominin evolution. However, diversity studies that apply methods currently used by neoecologists are rare in paleoanthropology and are also challenging due to diversity's unusual statistical properties. Here, we apply up-to-date analytical methods for understanding how species- and genus-level large mammalian diversity in the Omo-Turkana Basin changed through time and across space at multiple spatiotemporal scales (within each formation:102-3 km2 and 104-5 years; and within the basin as a whole: 103 km2 and 105 years). We found that, on average, Koobi Fora's large mammal community was more diverse than Nachukui's, which in turn was more diverse than Shungura's. Diversity was stable through time within each of these formations (alpha diversity), as was diversity in the basin as a whole (gamma diversity). Compositional dissimilarity between these three formations (beta diversity) was relatively low through time, with a 0.6 average proportion of shared species, suggesting dispersal acted to homogenize the region. Though alpha and gamma diversity were fairly stable through time, we do observe several notable peaks: during the KBS Member in Koobi Fora (30% increase), the Lokalalei Member in Nachukui (120% increase), and at 1.7 Ma in the entire basin (100% increase). We conclude by (1) demonstrating that habitat heterogeneity was an important factor influencing alpha diversity within each of the three formations, and (2) hypothesizing that diversity stability may have been driven by equilibrial dynamics in which overall diversity was constrained by resource availability, implying biotic interactions were an important factor in structuring the communities that included hominins as members. Our findings demonstrate the need to quantify how large mammal diversity changes across time and space in order to further our understanding of hominin ecology and evolution.
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Affiliation(s)
- Andrew Du
- Department of Organismal Biology and Anatomy, The University of Chicago, 1027 E 57th St, Chicago, IL 60637, USA.
| | - Zeresenay Alemseged
- Department of Organismal Biology and Anatomy, The University of Chicago, 1027 E 57th St, Chicago, IL 60637, USA
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Andrew Barr W. The Morphology of the Bovid Calcaneus: Function, Phylogenetic Signal, and Allometric Scaling. J MAMM EVOL 2018. [DOI: 10.1007/s10914-018-9446-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Forrest FL, Plummer TW, Raaum RL. Ecomorphological analysis of bovid mandibles from Laetoli Tanzania using 3D geometric morphometrics: Implications for hominin paleoenvironmental reconstruction. J Hum Evol 2018; 114:20-34. [DOI: 10.1016/j.jhevol.2017.09.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2014] [Revised: 09/16/2017] [Accepted: 09/23/2017] [Indexed: 11/16/2022]
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Three-Dimensional Geometric Morphometrics in Paleoecology. VERTEBRATE PALEOBIOLOGY AND PALEOANTHROPOLOGY 2018. [DOI: 10.1007/978-3-319-94265-0_14] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Rowan J, Locke EM, Robinson JR, Campisano CJ, Wynn JG, Reed KE. Fossil Giraffidae (Mammalia, Artiodactyla) from Lee Adoyta, Ledi-Geraru, and Late Pliocene Dietary Evolution in Giraffids from the Lower Awash Valley, Ethiopia. J MAMM EVOL 2016. [DOI: 10.1007/s10914-016-9343-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Elton S, Jansson AU, Meloro C, Louys J, Plummer T, Bishop LC. Exploring morphological generality in the Old World monkey postcranium using an ecomorphological framework. J Anat 2016; 228:534-60. [PMID: 26791626 DOI: 10.1111/joa.12428] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/09/2015] [Indexed: 11/28/2022] Open
Abstract
Nearly all primates are ecologically dependent on trees, but they are nonetheless found in an enormous range of habitats, from highly xeric environments to dense rainforest. Most primates have a relatively 'generalised' skeleton, enabling locomotor flexibility and facilitating other crucial functions, such as manual foraging and grooming. This paper explores the associations between habitat, locomotion and morphology in the forelimbs of cercopithecids (Old World monkeys), contextualising their skeletal ecomorphological patterns with those of other mammals, and complementing functional morphological analyses with phylogenetic comparative techniques. The ecomorphological signals present in the generalised primate postcranium, and how an ancestral arboreal 'bauplan' might be modified to incorporate terrestriality or exploit distinct arboreal substrates, are investigated. Analysis of ecomorphological variation in guenons indicates that terrestrial Chlorocebus species retain core elements of a general guenon form, with modifications for terrestriality that vary by species. Adaptation to different modes of arboreality has also occurred in Cercopithecus. The considerable morphological similarity in the guenons sampled emphasises the importance of generality in the primate postcranium - much forelimb variation appears to have emerged stochastically, with a smaller number of traits having a strong functional signal. Analysis of a broader sample of cercopithecids and comparison with felids, suids and bovids indicates that although the cercopithecid humerus has functional morphological signals that enable specimens to be assigned with a reasonable degree of certainty to habitat groups, there is considerable overlap in the specimens assigned to each habitat group. This probably reflects ecological dependence on trees, even in predominantly terrestrial species, as well as the multiple functions of the forelimb and, in some cases, wide geographic distributions that promote intraspecific variation. The use of phylogenetic correction reduced the discriminatory power of the models, indicating that, like allometry, phylogeny contains important ecomorphological information, and should not necessarily be factored out of analyses.
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Affiliation(s)
- Sarah Elton
- Department of Anthropology, University of Durham, Durham, UK
| | | | - Carlo Meloro
- Research Centre in Evolutionary Anthropology and Palaeoecology, School of Natural Sciences and Psychology, Liverpool John Moores University, Liverpool, UK
| | - Julien Louys
- Department of Archaeology and Natural History, School of Culture, History and Languages, The Australian National University, Canberra, ACT, Australia
| | - Thomas Plummer
- Department of Anthropology, Queens College, CUNY and NYCEP, Flushing, NY, USA
| | - Laura C Bishop
- Research Centre in Evolutionary Anthropology and Palaeoecology, School of Natural Sciences and Psychology, Liverpool John Moores University, Liverpool, UK
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Negash EW, Alemseged Z, Wynn JG, Bedaso ZK. Paleodietary reconstruction using stable isotopes and abundance analysis of bovids from the Shungura Formation of South Omo, Ethiopia. J Hum Evol 2015; 88:127-136. [PMID: 26341031 DOI: 10.1016/j.jhevol.2015.07.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Revised: 07/10/2015] [Accepted: 07/15/2015] [Indexed: 11/25/2022]
Abstract
Preservation of the stable carbon isotopic composition of fossil tooth enamel enables us to estimate the relative proportion of C3 versus C4 vegetation in an animal's diet, which, combined with analysis of faunal abundance, may provide complementary methods of paleoenvironmental reconstruction. To this end, we analyzed stable carbon isotopic composition (δ(13)C values) of tooth enamel from four bovid tribes (Tragelaphini, Aepycerotini, Reduncini, and Alcelaphini) derived from six members of the Shungura Formation (Members B, C, D, F, G, and L; ages from ca. 2.90-1.05 Ma (millions of years ago) in the Lower Omo Valley of southwestern Ethiopia. The bovids show a wide range of δ(13)C values within taxa and stratigraphic members, as well as temporal changes in the feeding strategies of taxa analyzed throughout the middle to late Pliocene and early Pleistocene. Such variation suggests that the use of actualistic approaches for paleoenvironmental reconstruction may not always be warranted. Alcelaphini was the only taxon analyzed that retained a consistent dietary preference throughout the sequence, with entirely C4-dominated diets. Reduncini had a mixed C3/C4 to C4-dominated diet prior to 2.4 Ma, after which this taxon shifted to a largely C4-dominated diet. Aepycerotini generally showed a mixed C3/C4 diet, with a period of increased C4 diet from 2.5 to 2.3 Ma. Tragelaphini showed a range of mixed C3/C4 diets, with a median value that was briefly nearer the C4 end member from 2.9 to 2.4 Ma but was otherwise towards the C3 end member. These isotopic results, combined with relative abundance data for these bovids, imply that the environment of the Lower Omo Valley consisted of a mosaic of closed woodlands, with riverine forests and open grasslands. However, our data also signify that the overall environment gradually became more open, and that C4 grasses became more dominant. Finally, these results help document the range and extent of environments and potential diets that were available to the four hominin species encountered in the Shungura sequence.
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Affiliation(s)
- Enquye W Negash
- Department of Anthropology, The George Washington University, Washington, DC 20052, USA
| | - Zeresenay Alemseged
- Department of Anthropology, The California Academy of Sciences, 55 Music Concourse Dr., San Francisco, CA 94118, USA.
| | - Jonathan G Wynn
- School of Geosciences, University of South Florida, 4202 E Fowler Ave. NES107, Tampa, FL 33620, USA
| | - Zelalem K Bedaso
- Department of Geology, University of Dayton, 300 College Park, Dayton, OH 45469-2364, USA
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