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- The DistoX2: a methodological solution to archaeological mapping in poorly accessible environmentsPublication . Almeida-Warren, Katarina; Braun, David R.; Carvalho, SusanaSpatial information is crucial to archaeological field research. From the plane-table to the total station, recent technological advances have enabled data collection to become fully digital and highly accurate. Nevertheless, the recent expansion of archaeological expeditions to novel environments often incompatible with modern mapping equipment, e.g. tropical forests or ephemeral shorelines, calls for further methodological innovations. Such projects, as well as those under logistic or financial limitations, are still largely reliant on more time consuming, less accurate, traditional approaches, e.g. offset or tape and compass methods. The DistoX2 is a digital, highly portable, and versatile hand-held instrument originally developed for speleological surveys where total stations and DGPSs are not feasible. However, the potential of the DistoX2 system as a spatial mapping tool in above-ground contexts has been surprisingly overlooked. Here, we present a first assessment of the applicability of the DistoX2 for archaeological mapping in non-speleological environments. We investigate precision and accuracy in controlled above-ground settings relative to two common methods of data collection - total station, and tape and compass. We test the relative precision of the DistoX2 when mounted on a tripod or operated in hand-held mode and discuss its applicability, and potential combined used, in the context of other increasingly popular methods - GNSS and SfM photogrammetry. With a mean error of approximate to 5.00 cm for horizontal readings and approximate to 2.00 cm for vertical readings, the DistoX2 is considerably more accurate than the tape and compass method (mu approximate to 67.00 cm horizontal; mu approximate to 3.00 cm vertical). While the DistoX2 exceeds the error thresholds of projects that require high spatial sensitivity (e.g. Palaeolithic excavations), it provides a reliable, low-cost and more accurate alternative to many projects that resort to more traditional methods. This fills an existent methodological and financial gap amongst the growing diversity of archaeological expeditions.
- Gorongosa by the sea: First Miocene fossil sites from the Urema Rift, central Mozambique, and their coastal paleoenvironmental and paleoecological contextsPublication . Habermann, Jörg M.; Alberti, Matthias; Aldeias, Vera; Alemseged, Zeresenay; Archer, Will; Bamford, Marion; Biro, Dora; Braun, David R.; Capelli, Cristian; Cunha, Eugenia; da Silva, Maria Ferreira; Luedecke, Tina; Madiquida, Hilario; Martinez, Felipe I.; Mathe, Jacinto; Negash, Enquye; Paulo, Luis M.; Pinto, Maria; Stalmans, Marc; Regala, Frederico Tata; Wynn, Jonathan G.; Bobe, Rene; Carvalho, SusanaThe East African Rift System (EARS) has played a central role in our understanding of human origins and vertebrate evolution in the late Cenozoic of Africa. However, the distribution of fossil sites along the rift is highly biased towards its northern extent, and the types of paleoenvironments are primarily restricted to fluvial and lacustrine settings. Here we report the discovery of the first fossil sites from the Urema Rift at Gorongosa National Park (central Mozambique) at the southern end of the EARS, and reconstruct environmental contexts of the fossils. In situ and surface fossils from the lower member of the Mazamba Formation, estimated to be of Miocene age, comprise mammals, reptiles, fishes, invertebrates, palms, and dicot trees. Fossil and geological evidence indicates a coastal-plain paleoenvironmental mosaic of riverine forest/woodland and estuarine habitats that represent the first coastal biomes identified in the Neogene EARS context. Receiving continental sediment from source terranes west of today's Urema Graben, estuarine sequences accumulated prior to rifting as compound incised-valley fills on a low-gradient coastal plain following transgression. Modern environmental analogues are extremely productive habitats for marine and terrestrial fauna, including primates. Thus, our discoveries raise the possibility that the Miocene coastal landscapes of Gorongosa were ecologically-favorable habitats for primates, providing relatively stable maritime climate and ecosystem conditions, year-round freshwater availability, and food both from terrestrial and marine sources. The emerging fossil record from Gorongosa is beginning to fill an important gap in the paleobiogeography of Africa as no fossil sites of Neogene age have previously been reported from the southernmost part of the EARS. Furthermore, this unique window into past continental-margin ecosystems of central Mozambique may allow us to test key paleobiogeographic hypotheses during critical periods of primate evolution.
- 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.
- A missing piece of the Papio puzzle: Gorongosa baboon phenostructure and intrageneric relationshipsPublication . Martinez, Felipe I.; Capelli, Cristian; Ferreira da Silva, Maria J.; Aldeias, Vera; Alemseged, Zeresenay; Archer, William; Bamford, Marion; Biro, Dora; Bobe, Rene; Braun, David R.; Habermann, Jörg M.; Luedecke, Tina; Madiquida, Hilario; Mathe, Jacinto; Negash, Enquye; Paulo, Luis M.; Pinto, Maria; Stalmans, Marc; Tata, Frederico; Carvalho, SusanaMost authors recognize six baboon species: hamadryas (Papio hamadryas), Guinea (Papio papio), olive (Papio anubis), yellow (Papio cynocephalus), chacma (Papio ursinus), and Kinda (Papio kindae). However, there is still debate regarding the taxonomic status, phylogenetic relationships, and the amount of gene flow occurring between species. Here, we present ongoing research on baboon morphological diversity in Gorongosa National Park (GNP), located in central Mozambique, south of the Zambezi River, at the southern end of the East African Rift System. The park exhibits outstanding ecological diversity and hosts more than 200 baboon troops. Gorongosa National Park baboons have previously been classified as chacma baboons (P. ursinus). In accordance with this, two mtDNA samples from the park have been placed in the same mtDNA Glade as the northern chacma baboons. However, GNP baboons exhibit morphological features common in yellow baboons (e.g., yellow fur color), suggesting that parapatric gene flow between chacma and yellow baboons might have occurred in the past or could be ongoing. We investigated the phenostructure of the Gorongosa baboons using two approaches: 1) description of external phenotypic features, such as coloration and body size, and 2) 3D geometric morphometric analysis of 43 craniofacial landmarks on 11 specimens from Gorongosa compared to a pan-African sample of 352 baboons. The results show that Gorongosa baboons exhibit a mosaic of features shared with southern P. cynocephalus and P. ursinus griseipes. The GNP baboon phenotype fits within a geographic clinal pattern of replacing allotaxa. We put forward the hypothesis of either past and/or ongoing hybridization between the gray-footed chacma and southern yellow baboons in Gorongosa or an isolation-by-distance scenario in which the GNP baboons are geographically and morphologically intermediate. These two scenarios are not mutually exclusive. We highlight the potential of baboons as a useful model to understand speciation and hybridization in early human evolution. (C) 2019 Elsevier Ltd. All rights reserved.
- The first Miocene fossils from coastal woodlands in the southern East African RiftPublication . Bobe, René; Aldeias, Vera; Alemseged, Zeresenay; Anemone, Robert L.; Archer, Will; Aumaître, Georges; Bamford, Marion K.; Biro, Dora; Bourlès, Didier L.; Doyle Boyd, Melissa; Braun, David R.; Capelli, Cristian; d’Oliveira Coelho, João; Habermann, Jörg M.; Head, Jason J.; Keddadouche, Karim; Kupczik, Kornelius; Lebatard, Anne-Elisabeth; Lüdecke, Tina; Macôa, Amélia; Martínez, Felipe I.; Mathe, Jacinto; Mendes, Clara; Paulo, Luis Meira; Pinto, Maria; Presnyakova, Darya; Püschel, Thomas A.; Regala, Frederico; Sier, Mark; Ferreira da Silva, Maria Joana; Stalmans, Marc; Carvalho, SusanaThe Miocene was a key time in the evolution of African ecosystems witnessing the origin of the African apes and the isolation of eastern coastal forests through an expanding arid corridor. Until recently, however, Miocene sites from the southeastern regions of the continent were unknown. Here, we report the first Miocene fossil teeth from the shoulders of the Urema Rift in Gorongosa National Park, Mozambique. We provide the first 1) radiometric ages of the Mazamba Formation, 2) reconstructions of paleovegetation in the region based on pedogenic carbonates and fossil wood, and 3) descriptions of fossil teeth. Gorongosa is unique in the East African Rift in combining marine invertebrates, marine vertebrates, reptiles, terrestrial mammals, and fossil woods in coastal paleoenvironments. The Gorongosa fossil sites offer the first evidence of woodlands and forests on the coastal margins of southeastern Africa during the Miocene, and an exceptional assemblage of fossils including new species.
- Quantifying traces of tool use: a novel morphometric analysis of damage patterns on percussive toolsPublication . Caruana, Matthew V.; Carvalho, Susana; Braun, David R.; Presnyakova, Darya; Haslam, Michael; Archer, Will; Bobe, René; Harris, John W. K.Percussive technology continues to play an increasingly important role in understanding the evolution of tool use. Comparing the archaeological record with extractive foraging behaviors in nonhuman primates has focused on percussive implements as a key to investigating the origins of lithic technology. Despite this, archaeological approaches towards percussive tools have been obscured by a lack of standardized methodologies. Central to this issue have been the use of qualitative, non-diagnostic techniques to identify percussive tools from archaeological contexts. Here we describe a new morphometric method for distinguishing anthropogenically-generated damage patterns on percussive tools from naturally damaged river cobbles. We employ a geomatic approach through the use of three-dimensional scanning and geographical information systems software to statistically quantify the identification process in percussive technology research. This will strengthen current technological analyses of percussive tools in archaeological frameworks and open new avenues for translating behavioral inferences of early hominins from percussive damage patterns.