Percorrer por autor "Bobe, René"
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- Afar fossil shows broad distribution and versatility of paranthropusPublication . Alemseged, Zeresenay; Spoor, Fred; Reed, Denné; Barr, W. Andrew; Geraads, Denis; Wynn, Jonathan G.; Bobe, RenéThe Afar depression in northeastern Ethiopia contains a rich palaeontological and archaeological record, which documents 6 million years of human evolution. Abundant faunal evidence links evolutionary patterns with palaeoenvironmental change as a principal underlying force1 . Many of the earlier hominin taxa recognized today are found in the Afar, but Paranthropus has been conspicuously absent from the region. Here we report on the discovery, in the Mille-Logya research area, of a partial mandible that we attribute to Paranthropus, dated to between 2.5 and 2.9 million years ago and found in a well-understood chronological and faunal context. The find is among the oldest fossils attributable to Paranthropus and indicates that this genus, from its earliest known appearance, had a greater geographic distribution than previously documented2 . Often seen as a dietary specialist feeding on tough food, the range of diverse habitats with which eastern African Paranthropus can now be associated shows that this suggested adaptive niche did not restrict its ability to disperse as widely as species of Australopithecus and early Homo. The discovery of Paranthropus in the Afar emphasizes how little is known about hominin evolution in eastern Africa during the crucial period between 3 and 2.5 million years ago, when this genus and the Homo lineage presumably emerged.
- The behavioural ecology of hominin locomotion: what can we learn from landscapes of fear and primate terrestriality?Publication . Hammond, Philippa; Bobe, René; Carvalho, SusanaA defining feature of the hominin clade is bipedality, often parcelled together with terrestriality. However, there is increasing evidence of locomotor diversity, both within the hominin clade and amongst the Miocene apes that came before them. There is also growing recognition that bipedalism might have arboreal origins and that arboreality persisted in several hominin taxa, including our own genus Homo. Furthermore, the difference between terms like “habitual” and “obligate” bipedality is not clearly defined and is often inferred from fossil features, rather than a description of each behaviour in vivo. Combining fossil and palaeoecological evidence with insights from behavioural ecology facilitates new interpretations of evolutionary pathways and highlights the importance of considering convergent evolution in the emergence of locomotor traits and characteristics. Taking such an approach also moves away from assumptions of a straight-line trajectory towards modern human locomotion and explores the likelihood that independent forms of bipedality and terrestriality arose at different times and in different combinations with other features of ape morphology and behaviour. Evidence from extant primate species can broaden our understanding of the correlates, causes, and consequences of terrestriality and can be used to generate hypotheses which are then explored further using paleontological methods. In this paper, we explore the evolutionary origins of hominin locomotion, but extend our review to include broader timescales, a wider range of primate taxa, and an integrated set of methods and disciplines for generating and testing hypotheses about locomotion. Perceived risk (or, the “landscape of fear”) is a key pressure that has selected for primate arboreality – particularly nocturnal arboreality. We propose that shifts in Plio-Pleistocene landscapes of fear – caused by declining carnivoran abundance and diversity – might also have been a key selection pressure in changes to primate locomotion, particularly papionin and hominid terrestriality. We discuss this hypothesis and propose future research avenues to explore it further. Not only will such research provide a more nuanced view of the causes and consequences of a rare behavioural trait in primates, but it could ultimately help us explain how one group of African apes came to spend all their time on the ground, and how that made them human.
- Early oldowan technology thrived during pliocene environmental change in the Turkana Basin, Kenya.Publication . Braun, David R.; Palcu Rolier, Dan V.; Advokaat, Eldert L.; Archer, Will; Baraki, Niguss G.; Biernat, Maryse D.; Beaudoin, Ella; Behrensmeyer, Anna K.; Bobe, René; Elmes, Katherine; Forrest, Frances; Hammond, Ashley S.; Jovane, Luigi; Kinyanjui, Rahab N.; de Martini, Ana P.; Mason, Paul R D.; McGrosky, Amanda; Munga, Joanne; Ndiema, Emmanuel K.; Patterson, David B.; Reeves, Jonathan S.; Roman, Diana C.; Sier, Mark J.; Srivastava, Priyeshu; Tuosto, Kristen; Uno, Kevin T.; Villaseñor, Amelia; Wynn, Jonathan G.; Harris, John W. K.; Carvalho, SusanaApproximately 2.75 million years ago, the Turkana Basin in Kenya experienced environmental changes, including increased aridity and environmental variability. Namorotukunan is a newly discovered archaeological site which provides a window into hominin behavioral adaptations. This site lies within the upper Tulu Bor and lower Burgi members of the Koobi Fora Formation (Marsabit District, Kenya), presently a poorly understood time interval due to large-scale erosional events. Moreover, this locale represents the earliest known evidence of Oldowan technology within the Koobi Fora Formation. Oldowan sites, older than 2.6 million years ago, are rare, and these typically represent insights from narrow windows of time. In contrast, Namorotukunan provides evidence of tool-making behaviors spanning hundreds of thousands of years, offering a unique temporal perspective on technological stability. The site comprises three distinct archaeological horizons spanning approximately 300,000 years (2.75 − 2.44 Ma). Our findings suggest continuity in tool-making practices over time, with evidence of systematic selection of rock types. Geological descriptions and chronological data, provide robust age control and contextualize the archaeological finds. We employ multiple paleoenvironmental proxies, to reconstruct past ecological conditions. Our study highlights the interplay between environmental shifts and technological innovations, shedding light on pivotal factors in the trajectory of human evolution.
- Evolution of craniofacial shape in relation to sexual dimorphism in theropithecus and papioPublication . Ossorio, Ángeles; Figueroa-Torrejón, Ambra; Buston, Rodrigo; Caldon, Matteo; Mathe, Jacinto; Doria, Giuliano; Gippoliti, Spartaco; Volta, Antonella; Silva, María Joana Ferreira da; Bobe, René; Carvalho, Susana; Capelli, Cristian; Martínez, Felipe I.Introduction: Sexual dimorphism in cranial morphology is a significant aspect of primate evolution, providing insights into evolutionary pressures and mating systems in different species. This study focuses on cranial sexual dimorphism in Papio and Theropithecus, two closely related genera within the tribe Papionini.Methods: Using geometric morphometric techniques, we analyzed 570 cranial specimens from both genera, with data sourced from various studies and repositories. Thirty craniofacial landmarks were defined and analyzed through Geometric Morphometrics tools to evaluate shape variation.Results: Our findings reveal distinct morphological clusters for each genus and sex, with Papio and Theropithecus exhibiting significant sexual dimorphism. The results distinguish genera and sex-based groups, indicating differential impacts of size on shape across groups. The findings suggest that while sexual dimorphism is stable in magnitude within each genus, the specific morphological manifestations differ.Discussion: This research advances our understanding of the evolutionary mechanisms driving sexual dimorphism and emphasizes the need for further studies to explore the genetic and environmental factors influencing these differences. The innovative approach and comprehensive dataset provide a robust framework for future investigations into primate cranial morphology and its evolutionary implications.
- Genomic variation in baboons from central Mozambique unveils complex evolutionary relationships with other Papio speciesPublication . Santander, Cindy; Molinaro, Ludovica; Mutti, Giacomo; Martínez, Felipe I.; Mathe, Jacinto; Ferreira da Silva, Maria J.; Caldon, Matteo; Oteo-Garcia, Gonzalo; Aldeias, Vera; Archer, Will; Bamford, Marion; Biro, Dora; Bobe, René; Braun, David R.; Hammond, Philippa; Lüdecke, Tina; Pinto, Maria J.; Meira Paulo, Luis; Stalmans, Marc; Regala, Frederico; Bertolini, Francesco; Moltke, Ida; Raveane, Alessandro; Pagani, Luca; Carvalho, Susana; Capelli, CristianBackground Gorongosa National Park in Mozambique hosts a large population of baboons, numbering over 200 troops. Gorongosa baboons have been tentatively identified as part of Papio ursinus on the basis of previous limited morphological analysis and a handful of mitochondrial DNA sequences. However, a recent morphological and morphometric analysis of Gorongosa baboons pinpointed the occurrence of several traits intermediate between P. ursinus and P. cynocephalus, leaving open the possibility of past and/or ongoing gene flow in the baboon population of Gorongosa National Park. In order to investigate the evolutionary history of baboons in Gorongosa, we generated high and low coverage whole genome sequence data of Gorongosa baboons and compared it to available Papio genomes. Results We confirmed that P. ursinus is the species closest to Gorongosa baboons. However, the Gorongosa baboon genomes share more derived alleles with P. cynocephalus than P. ursinus does, but no recent gene flow between P. ursinus and P. cynocephalus was detected when available Papio genomes were analyzed. Our results, based on the analysis of autosomal, mitochondrial and Y chromosome data, suggest complex, possibly male-biased, gene flow between Gorongosa baboons and P. cynocephalus, hinting to direct or indirect contributions from baboons belonging to the “northern” Papio clade, and signal the presence of population structure within P. ursinus. Conclusions The analysis of genome data generated from baboon samples collected in central Mozambique highlighted a complex set of evolutionary relationships with other baboons. Our results provided new insights in the population dynamics that have shaped baboon diversity.
- 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.
- Modern African ecosystems as landscape-scale analogues for reconstructing woody cover and early hominin environmentsPublication . Negash, Enquye W.; Alemseged, Zeresenay; Barr, W. Andrew; Behrensmeyer, Anna K.; Blumenthal, Scott A.; Bobe, René; Carvalho, Susana; Cerling, Thure E.; Chritz, Kendra L.; McGuire, Elizabeth; Uno, Kevin T.; Wood, Bernard; Wynn, Jonathan G.Reconstructing habitat types available to hominins and inferring how the paleo-landscape changed through time are critical steps in testing hypotheses about the selective pressures that drove the emergence of bipedalism, tool use, a change in diet, and progressive encephalization. Change in the amount and distribution of woody vegetation has been suggested as one of the important factors that shaped early hominin evolution. Previous models for reconstructing woody cover at eastern African hominin fossil sites used global-scale modern soil comparative datasets. Our higher-spatial-resolution study of carbon isotopes in soil organic matter is based on 26 modern African locations, ranging from tropical grass-dominated savannas to forests. We used this dataset to generate a new Eastern Africa -specific Woody Cover Model (EAWCM), which indicates that eastern African hominin sites were up to 13% more wooded than reconstructions based on previous models. Reconstructions using the EAWCM indicate widespread woodlands/bushlands and wooded grasslands and a shift toward C4-dominated landscapes in eastern Africa over the last 6 million years. Our results indicate that mixed tree-C4 grass savannas with 10-80% tree cover (but not pure grasslands with <10 % tree cover) dominated early hominin paleoenvironments. Landscapes with these biomes are marked by exceptional heterogeneity, which posed challenges and offered opportunities to early hominins that likely contributed to major behavioral and morphological shifts in the hominin clade. (c) 2024 Elsevier Ltd.
- Modern African ecosystems as landscape-scale analogues for reconstructing woody cover and early hominin environmentsPublication . Negash, Enquye W.; Alemseged, Zeresenay; Barr, W. Andrew; Behrensmeyer, Anna K.; Blumenthal, Scott A.; Bobe, René; Carvalho, Susana; Cerling, Thure E.; Chritz, Kendra L.; McGuire, Elizabeth; Uno, Kevin T.; Wood, Bernard; Wynn, Jonathan G.Reconstructing habitat types available to hominins and inferring how the paleo-landscape changed through time are critical steps in testing hypotheses about the selective pressures that drove the emergence of bipedalism, tool use, a change in diet, and progressive encephalization. Change in the amount and distribution of woody vegetation has been suggested as one of the important factors that shaped early hominin evolution. Previous models for reconstructing woody cover at eastern African hominin fossil sites used global-scale modern soil comparative datasets. Our higher-spatial-resolution study of carbon isotopes in soil organic matter is based on 26 modern African locations, ranging from tropical grass-dominated savannas to forests. We used this dataset to generate a new Eastern Africa especific Woody Cover Model (EAWCM), which indicates that eastern African hominin sites were up to 13% more wooded than reconstructions based on previous models. Reconstructions using the EAWCM indicate widespread woodlands/bushlands and wooded grasslands and a shift toward C4-dominated landscapes in eastern Africa over the last 6 million years.
- 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.
- The primates of gorongosa national park, MozambiquePublication . Carvalho, Susana; Anemone, Robert L.; de Oliveira Coelho, João; Bobe, RenéThis contribution is an introduction to and synthesis of the special issue of the AJBA on Primate Adaptations in a Highly Seasonal and Heterogeneous African Ecosystem. The eight research papers in this special issue provide the first compilation of primatological research to emerge from Gorongosa National Park and represent a major landmark in the development of primatology as a science in Mozambique. Primatological field studies in the park were initiated in 2016 under the umbrella of the Paleo-Primate Project Gorongosa with the aim of exploring the deep time evolutionary history of the Gorongosa ecosystem and establishing a long-term primatological field research program. This initiative has resulted in the training of a new generation of primatologists, including the first from Mozambique. The papers in this volume focus on the behavior, ecology, adaptations, and genomics of baboons and vervet monkeys, and set the stage for the study of other primates in Gorongosa, including samango monkeys and nocturnal strepsirrhines. The environmental characteristics of the Gorongosa ecosystem, with major rivers and lakes in a dynamic mosaic of forests, woodlands, wetlands, and grasslands, and rich biodiversity, make Gorongosa a suitable analog for the environments in which early hominins are thought to have evolved. This special issue is dedicated to the memory of our dear friend and colleague Dr. Marc Stalmans, who was the Director of Science of Gorongosa National Park from 2012 to 2025.