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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.
- 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 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.
- Effects of an extreme weather event on primate populationsPublication . Beardmore-Herd, Megan; Palmer, Meredith S.; Gaynor, Kaitlyn M.; Carvalho, SusanaObjectives: With contemporary, human-induced climate change at a crisis point, extreme weather events (e.g., cyclones, heat waves, floods) are becoming more frequent, intense, and difficult to predict. These events can wreak rapid and significant changes on ecosystems; thus, it is imperative to understand how wildlife communities respond to these disruptions. Primates are perceived as being a largely adaptable order, but we often lack the quantitative data to rigorously assess how they are impacted by extreme environmental change. Leveraging detections from a long-term camera trap survey, this opportunistic study reports the effects of an extreme weather event on a little-studied population of free-ranging primates in Gorongosa National Park, Mozambique. Materials and Methods: We examined shifts in gray-footed chacma baboon (Papio ursinus griseipes) and vervet monkey (Chlorocebus pygerythrus) spatial distribution and relative abundance following Cyclone Idai—a category four tropical cyclone that struck Mozambique in March 2019. Results: Baboon spatial distributions were impacted in the first month after the cyclone, with more detections in areas where flooding was less severe. Spatial distributions renormalized once floodwaters began to recede. We describe vervet monkey spa tial distribution trends, though sample size limitations inhibited statistical analysis. Primate relative abundance did not appear to substantially decrease following the cyclone, suggesting troops were able to adopt behavioral adjustments to evade rising floodwaters. Discussion: These findings highlight the behavioral flexibility of Gorongosa's primates and their ability to adapt to extreme—if temporary—disruptions, with implications for primate conservation in the Anthropocene and research into how rapid climatic events may have shaped primate evolution.