Reassessing the role of carnivores in the formation of FLK North 3 (Olduvai Gorge, Tanzania): A pilot taphonomic analysis using Artificial Intelligence tools

FLK North (FLK N) (Bed I, Olduvai Gorge, Tanzania) is one of the best examples of a palimpsest where felids, hyenids and hominins made use of the same space without or with minimal interaction between hominins and the other two carnivores. Felids have been interpreted as the main accumulators and carcass consumers followed by frequent hyenid intervention. The presence of hominins at this site has been documented through the discovery of stone tools. Here, we test previous taphonomic interpretations of this site through the application of Artificial Intelligence (AI) tools (computer vision applied to bidimensional images of tooth pits) to taxonomically discriminate carnivore-made tooth marks. The bones we analyzed constitute a small sample, being a preliminary study of bone surface modifications (BSM) through the application of AI to a sample of the FLK N archaeofaunal assemblage (mostly to Level 3 fossils), pending access to the larger excavated collections. The results obtained in the present study show that the marks analyzed have been generated both by hyenids and felids. The slight predominance of hyena tooth marks is expected, since the bone sample used is dominated by long limb bones, and hyenas are the most likely agent causing long bone breakage, although felids also break bones of carcasses smaller than 150 kg as documented in the site. Felid impact, in at least three cases, is documented with tooth marks imprinted by felids and hyenas occurring on the same specimens. Felid-hyenid interaction is, thus, documented though the deep learning methods applied. The limited number of specimens where both agents are documented suggest that both hyenids and felids were independently breaking a substantial part of the bones at FLK N. This preliminarily modifies previous interpretations that attributed most long bone fragmentation exclusively to hyenas

Neo-taphonomic analysis of the Misiam leopard lair from Olduvai Gorge (Tanzania): understanding leopard–hyena interactions in open settings

Misiam is a modern wildebeest-dominated accumulation situated in a steep ravine covered with dense vegetation at Olduvai Gorge (Tanzania). It is interpreted here as a leopard lair to which carcasses have been transported for several years. Felid-specific bone damage patterns, felid-typical skeletal part profiles, taxonomic specialization and the physical presence of leopards observed by the authors show that leopards at Misiam can be specialized medium-sized carcass accumulators. Hyenas also intervened at intervals in the modification of the retrieved faunal assemblage. This makes Misiam a carnivore palimpsest. Here, we additionally show that leopards only transport and accumulate carcasses on occasions, that they can seem highly specialized despite being dietary generalists, and that such a behaviour may be prompted by seasonal competition or during the breeding season or both. Misiam is the first open-air leopard lair with a dense bone accumulation reported. There, leopards engaged in intensive accumulation of carcasses during the wet season, when the southern Serengeti short-grass plains undergo the effect of the famous wildebeest migration and this migratory species reaches the gorge. The ecological importance of this behaviour and its relevance as a proxy for reconstructing prehistoric carnivore behaviours are discussed

En busca del primer Homo: gestión de la investigación arqueológica en la Garganta de Olduvai (Tanzania)

[EN] The sites at Olduvai Gorge (Tanzania) constitute a unique venue for the study of the first members of the genus Homo. The large amount of fossils recovered and the good state of preservation of these sites have boosted archaeological research in the Gorge throughout the years. The Olduvai Paleoanthropology and Paleoecology Project (TOPPP) research team, present at the Gorge since 2006, launched the construction of the Aguirre-Mturi Scientific Station within the limits of the Ngorongoro National Park with the aim of improving the working conditions and provide a safe working space. The safeguard of the archaeological materials was also one of the cornerstones during the design process and building of the station. The laboratory allows almost immediate cleaning, analysis and restoration of the materials recovered during field work. Meanwhile, in Spain, the Institute of Evolution in Africa (IDEA), current headquarters of the TOPPP team, was founded with the aim of promoting the study of African paleoanthropology and the origins of humankind in Africa. Along with the research work, TOPPP strives to bring the scientific knowledge to the general public in several ways, including the management of temporary and permanent exhibitions in Spain and Tanzania.[ES] Los yacimientos de la Garganta de Olduvai (Tanzania) constituyen un enclave único para el estudio de los primeros representantes del género Homo. La buena preservación de estos yacimientos y la cantidad de fósiles hallados en ellos posibilita que se sigan desarrollando excavaciones arqueológicas en este lugar. El equipo de investigación The Olduvai Paleoanthropology and Paleoecology Project (TOPPP), que trabaja en estos yacimientos desde 2006, promovió la construcción de la Estación Científica Aguirre-Mturi con el propósito de mejorar las condiciones laborales del personal investigador y de hacer del campamento un lugar seguro de trabajo. Durante el proceso de creación y construcción se tuvo en cuenta la salvaguarda de los materiales arqueológicos, y gracias a la existencia de un laboratorio en el campamento, es posible realizar tareas como la limpieza, el análisis y la restauración del material recuperado. En España, la creación del Instituto de Evolución en África (IDEA), sede actual del equipo TOPPP, nace con el objetivo de promover el estudio de la paleoantropología africana y el origen del ser humano en África. Junto a los trabajos de investigación, TOPPP realiza una intensa actividad divulgativa donde destaca la creación de exposiciones temporales y permanentes en España y Tanzania.A la Comisión para la Ciencia y la Tecnología (COSTECH), a la Autoridad del Área de Conservación del Ngorongoro (NCAA) y al Departamento de Antigüedades y al Ministerio de Turismo y Recursos Naturales en Tanzania por el permiso para investigar en la Garganta de Olduvai. Al Ministerio de Ciencia, Innovación y Universidades por el proyecto concedido (HAR2017-82463-C4-1-P) y por la financiación para los contratos predoctorales de Formación de Profesorado Universitario (FPU) de MVR y JA; al Ministerio de Cultura a través del Instituto de Patrimonio Cultural de España por las ayudadas concedidas para Proyectos Arqueológicos en el Exterior, y a la Fundación Palarq por las ayudas para apoyar las Misiones de Arqueología y Paleontología Españolas en el en el extranjero.Peer reviewe

Early Pleistocene faunivorous hominins were not kleptoparasitic, and this impacted the evolution of human anatomy and socio-ecology

Humans are unique in their diet, physiology and socio-reproductive behavior compared to other primates. They are also unique in the ubiquitous adaptation to all biomes and habitats. From an evolutionary perspective, these trends seem to have started about two million years ago, coinciding with the emergence of encephalization, the reduction of the dental apparatus, the adoption of a fully terrestrial lifestyle, resulting in the emergence of the modern anatomical bauplan, the focalization of certain activities in the landscape, the use of stone tools, and the exit from Africa. It is in this period that clear taphonomic evidence of a switch in diet with respect to Pliocene hominins occurred, with the adoption of carnivory. Until now, the degree of carnivorism in early humans remained controversial. A persistent hypothesis is that hominins acquired meat irregularly (potentially as fallback food) and opportunistically through klepto-foraging. Here, we test this hypothesis and show, in contrast, that the butchery practices of early Pleistocene hominins (unveiled through systematic study of the patterning and intensity of cut marks on their prey) could not have resulted from having frequent secondary access to carcasses. We provide evidence of hominin primary access to animal resources and emphasize the role that meat played in their diets, their ecology and their anatomical evolution, ultimately resulting in the ecologically unrestricted terrestrial adaptation of our species. This has major implications to the evolution of human physiology and potentially for the evolution of the human brain

Computer vision enables taxon-specific identification of African carnivore tooth marks on bone

Abstract Taphonomic works aim at discovering how paleontological and archaeofaunal assemblages were formed. They also aim at determining how hominin fossils were preserved or destroyed. Hominins and other mammal carnivores have been co-evolving, at least during the past two million years, and their potential interactions determined the evolution of human behavior. In order to understand all this, taxon-specific carnivore agency must be effectively identified in the fossil record. Until now, taphonomists have been able to determine, to some degree, hominin and carnivore inputs in site formation, and their interactions in the modification of part of those assemblages. However, the inability to determine agency more specifically has hampered the development of taphonomic research, whose methods are virtually identical to those used several decades ago (lagged by a high degree of subjectivity). A call for more objective and agent-specific methods would be a major contribution to the advancement of taphonomic research. Here, we present one of these advances. The use of computer vision (CV) on a large data set of images of tooth marks has enabled the objective discrimination of taxon-specific carnivore agency up to 88% of the testing sample. We highlight the significance of this method in an interdisciplinary interplay between traditional taphonomic-paleontological analysis and artificial intelligence-based computer science. The new questions that can be addressed with this will certainly bring important changes to several ideas on important aspects of the human evolutionary process

A taphonomic analysis of PTK (Bed I, Olduvai Gorge) and its bearing on the interpretation of the dietary and eco-spatial behaviors of early humans

Here, we present a thorough taphonomic analysis of the 1.84 million-year-old site of Phillip Tobias Korongo (PTK), Bed I, Olduvai Gorge. PTK is one of the new archaeological sites documented on the FLK Zinj paleolandscape, in which FLK 22 level was deposited and covered by Tuff IC. Therefore, PTK is pene-contemporary with these sites: FLK Zinj, DS, AMK and AGS. The occurrence of these sites within a thin clay unit of ∼20 cm, occupying not only the same vertically discrete stratigraphic unit, but also the same paleosurface, with an exceptional preservation of the archaeological record in its primary depositional locus, constitutes a unique opportunity to explore early hominin behavioral diversity at the most limited geochronological scale possible. The Olduvai Bed I sites have been the core of behavioral modelling for the past half a century, and the newly discovered sites, excavated with 21st century technology, will increase significantly our understanding of early human adaptive patterns. Here, we present PTK as another assemblage where faunal resources were acquired by hominins prior to any carnivore, and where stone-tool assisted bulk defleshing was carried out. The abundance of juvenile individuals extends our understanding, as in Kanjera (Kenya), about the hunting skills of early Homo sensu lato. The increasing number of sites, where bulk defleshing of small and medium-sized carcasses took place is underscoring the importance of meat in the diets of some of the early hominins, and their patterned use of the space for food processing and consumption. The patterning emerging has a profound importance for the evolution of some of the features that have traditionally been used to identify the behavior of the genus Homo

A symbolic Neanderthal accumulation of large herbivore crania

This work examines the possible behaviour of Neanderthal groups at the Cueva Des-Cubierta (central Spain) via the analysis of the latter’s archaeological assemblage. Alongside evidence of Mousterian lithic industry, Level 3 of the cave infill was found to contain an assemblage of mammalian bone remains dominated by the crania of large ungulates, some associated with small hearths. The scarcity of post-cranial elements, teeth, mandibles and maxillae, along with evidence of anthropogenic modification of the crania (cut and percussion marks), indicates that the carcasses of the corresponding animals were initially processed outside the cave, and the crania were later brought inside. A second round of processing then took place, possibly related to the removal of the brain. The continued presence of crania throughout Level 3 indicates that this behaviour was recurrent during this level’s formation. This behaviour seems to have no subsistence-related purpose but to be more symbolic in its intent