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The Old World fossil record of the family Camelidae is patchy, but a new partial cranium and some other remains of Camelus grattardi from the Mille-Logya Project area in the Afar, Ethiopia, greatly increase the fossil record of the genus in Africa. These new data – together with analysis of unpublished and recently published material from other sites, and reappraisal of poorly known taxa – allow for a comprehensive phylogenetic analysis showing that C. grattardi is the earliest (2.2–2.9 Ma) and most basal species of the genus. We also show that the lineages leading to the extant taxa C. dromedarius and C. bactrianus diverged much higher in the tree, suggesting a recent age for this divergence. A late divergence date between the extant species is consistent with the absence of any fossil forms that could be ancestral, or closely related, to any of the extant forms before the late Pleistocene, but stands in contrast to molecular estimates which place the divergence between the dromedary and the Bactrian camel between 8 and 4 million years ago.

The Eyasi Plateau Paleontological Expedition (EPPE) Laetoli specimen database contains 13716 records of plant and animal fossils (ca. 28248 specimens) collected by EPPE field teams working at Laetoli, Tanzania between 1998 and 2005. This dataset is a digital version of the original hard-copy specimen catalog, and it documents the discovery, stratigraphic provenience and taxonomic diversity of Plio-Pleistocene fauna and flora in northern Tanzania between 4.4 Ma and >200 ka. Laetoli is renowned for the discovery of important hominin fossils, including the lectotype for Australopithecus afarensis, one of our early hominin ancestors, the first record of Paranthropus aethiopicus outside Kenya-Ethiopia, and an early record of our own species Homo sapiens. This database is one of the few publicly available palaeoanthropological fossil datasets and serves as an example for expanding open access to primary fossil occurrence data in palaeoanthropology. The taxonomic identifications appearing in this dataset are the original field identifications and are provisional. Any taxonomic analysis employing this dataset should refer to updated taxonomic identifications published by specialists.

Fossil endocasts record features of brains from the past: size, shape, vasculature, and gyrification. These data, alongside experimental and comparative evidence, are needed to resolve questions about brain energetics, cognitive specializations, and developmental plasticity. Through the application of interdisciplinary techniques to the fossil record, paleoneurology has been leading major innovations. Neuroimaging is shedding light on fossil brain organization and behaviors. Inferences about the development and physiology of the brains of extinct species can be experimentally investigated through brain organoids and transgenic models based on ancient DNA. Phylogenetic comparative methods integrate data across species and associate genotypes to phenotypes, and brains to behaviors. Meanwhile, fossil and archeological discoveries continuously contribute new knowledge. Through cooperation, the scientific community can accelerate knowledge acquisition. Sharing digitized museum collections improves the availability of rare fossils and artifacts. Comparative neuroanatomical data are available through online databases, along with tools for their measurement and analysis. In the context of these advances, the paleoneurological record provides ample opportunity for future research. Biomedical and ecological sciences can benefit from paleoneurology’s approach to understanding the mind as well as its novel research pipelines that establish connections between neuroanatomy, genes and behavior. Recent advances in paleoneurology are collated together in this comprehensive review, linking neuroanatomy to genes and behavior. We provide guidance to the next generation of researchers to move the field forward.

Several hypotheses posit a link between the origin of Homo and climatic and environmental shifts between 3 and 2.5 Ma. Here we report on new results that shed light on the interplay between tectonics, basin migration and faunal change on the one hand and the fate of Australopithecus afarensis and the evolution of Homo on the other. Fieldwork at the new Mille-Logya site in the Afar, Ethiopia, dated to between 2.914 and 2.443 Ma, provides geological evidence for the northeast migration of the Hadar Basin, extending the record of this lacustrine basin to Mille-Logya. We have identified three new fossiliferous units, suggesting in situ faunal change within this interval. While the fauna in the older unit is comparable to that at Hadar and Dikika, the younger units contain species that indicate more open conditions along with remains of Homo . This suggests that Homo either emerged from Australopithecus during this interval or dispersed into the region as part of a fauna adapted to more open habitats. Key events in human evolution are thought to have occurred between 3 and 2.5 Ma, but the fossil record of this period is sparse. Here, Alemseged et al. report a new fossil site from this period, Mille-Logya, Ethiopia, and characterize the geology, basin evolution and fauna, including specimens of Homo .

Little is known about the dynamics of small mammals in tropical savanna: a critical gap in our understanding of Africa's best known ecosystems. Historical evidence suggested small mammals peak in abundance (outbreak) in Serengeti National Park (SNP), as in agricultural systems. We asked 1) what are bottom–up drivers of small mammals and 2) do predators have top–down effects? We documented dynamics of small mammals, birds of prey, and mammalian carnivores in SNP and agricultural areas. We used climatic fluctuations and differences between unmodified and agricultural systems as perturbations to examine trophic processes, key to understanding responses to climate change and increasing human pressures. Data were derived from intermittent measures of abundance collected 1968–1999, combined with systematic sampling 2000–2010 to construct a 42-year time series. Data on abundance of black-shouldered kites (1968–2010), eight other species of rodent-eating birds (1997–2010), and 10 carnivore species (1993–2010) were also collated. Outbreaks occurred every 3–5 years in SNP, with low or zero abundance between peaks. There was a positive relationship between rainfall in the wet season and 1) small mammal abundance and 2) the probability of an outbreak, both of which increased with negative Southern Oscillation Index values. Rodent-eating birds and carnivores peaked 6–12 months after small mammals. In agricultural areas, abundance remained higher than in natural habitats. Abundances of birds of prey and mammalian carnivores were extremely low in these areas and not related to small mammal abundance. Small mammals are an important food resource for higher trophic levels in the Serengeti ecosystem. Changes in climate and land use may alter their future dynamics, with cascading consequences for higher trophic levels, including threatened carnivores. Although outbreaks cause substantial damage to crops in agricultural areas, small mammals also play a vital role in maintaining some of the diversity and complexity found in African savanna ecosystems.

First evidence of tool use Until now, the earliest evidence for tool use by our ancestors or their relatives was from two sites in Ethiopia's Awash Valley. Stone tools manufactured about 2.5 million years ago were found at Gona, and cut-marked bones of about the same age were found in the Middle Awash. The suspicion that hominins used tools even earlier has now been borne out by the discovery at nearby Dikika of two bones, one from a large ungulate, with cut and percussion marks consistent with the use of stone tools to remove flesh and extract bone marrow. The marked bones are about 3.4 million years old and are probably the work of Australopithecus afarensis , the only hominin known to have been in the Awash Valley at this time, and famously the species to which the iconic Lucy (from Hadar, Ethiopia) and the juvenile Selam (or DIK-1-1, from Dikika) belong. The earliest direct evidence for stone tools is between 2.6 and 2.5 million years old and comes from Gona, Ethiopia. These authors report bones from Dikika, Ethiopia, dated to around 3.4 million years ago and marked with cuts indicative of the use of stone tools to remove flesh and extract bone marrow. This is the earliest known evidence of stone tool use, and might be attributed to the activities of Australopithecus afarensis. The oldest direct evidence of stone tool manufacture comes from Gona (Ethiopia) and dates to between 2.6 and 2.5 million years (Myr) ago 1 . At the nearby Bouri site several cut-marked bones also show stone tool use approximately 2.5 Myr ago 2 . Here we report stone-tool-inflicted marks on bones found during recent survey work in Dikika, Ethiopia, a research area close to Gona and Bouri. On the basis of low-power microscopic and environmental scanning electron microscope observations, these bones show unambiguous stone-tool cut marks for flesh removal and percussion marks for marrow access. The bones derive from the Sidi Hakoma Member of the Hadar Formation. Established 40 Ar– 39 Ar dates on the tuffs that bracket this member constrain the finds to between 3.42 and 3.24 Myr ago, and stratigraphic scaling between these units and other geological evidence indicate that they are older than 3.39 Myr ago. Our discovery extends by approximately 800,000 years the antiquity of stone tools and of stone-tool-assisted consumption of ungulates by hominins; furthermore, this behaviour can now be attributed to Australopithecus afarensis .

The area of the Inner Asian Mountain Corridor (IAMC) follows the foothills and piedmont zones around the northern limits of Asia’s interior mountains, connecting two important areas for human evolution: the Fergana valley and the Siberian Altai. Prior research has suggested the IAMC may have provided an area of connected refugia from harsh climates during the Pleistocene. To date, this region contains very few secure, dateable Pleistocene sites, but its widely available carbonate units present an opportunity for discovering cave sites, which generally preserve longer sequences and organic remains. Here we present two models for predicting karstic cave and rockshelter features in the Kazakh portion of the IAMC. The 2018 model used a combination of lithological data and unsupervised landform classification, while the 2019 model used feature locations from the results of our 2017–2018 field surveys in a supervised classification using a minimum-distance classifier and morphometric features derived from the ASTER digital elevation model (DEM). We present the results of two seasons of survey using two iterations of the karstic cave models (2018 and 2019), and evaluate their performance during survey. In total, we identified 105 cave and rockshelter features from 2017–2019. We conclude that this model-led approach significantly reduces the target area for foot survey.

Recent taphonomic studies have shown that avian predators such as owls are responsible for most small-mammal fossil accumulations, and that predators cause bone loss and breakage as well as modification to the surface of bones that are preserved. However, the specific physiochemical alterations and the alterations of bone microstructures that predators induce remain poorly understood. In order to better separate and characterize the effects of bone digestion by owls, we performed an experimental study to simulate digestion by a predator. We put fresh rodent long bones into various solutions to simulate the digestive effects of predators. We first tested an acid solution, followed by other solutions containing key enzymes such as trypsin, lipase, and trypsin + lipase. Next, we compared the results of the simulated digestion experiments with partly digested long bones recovered from Tyto alba and Bubo bubo pellets. We observed that acid action alone did not reproduce the modifications observed on bones from owl pellets, while the enzymatic activity (notably trypsin and trypsin + lipase) produced modifications most similar to those observed on the bones from the owl pellets. These results open a promising field of future experimentation to better understand the early diagenetic modification induced in small mammal bones by digestion, which can improve our ability to recognize the role of nocturnal predators in fossil accumulations.

We describe here a new species of gigantic otter, Enhydriodon dikikae, sp. nov., from the Pliocene of Dikika, in the lower Awash valley of Ethiopia. The holotype consists of an associated snout and mandible, and is the most complete fossil specimen of a large bunodont otter. In some features, such as its very large size, the loss of anterior premolars, the tall protocone of P4, and the divided paraconid of m1, this species illustrates the culmination of general trends in this group, but the most remarkable part of its dentition is the broad incisor arch and powerful canine battery. The purported distinction between Enhydriodon and Sivaonyx is discussed, and the hypothesis of distinct African and Asian lineages is rejected. Postcranial remains confirm that Enhydriodon dikikae, sp. nov., was probably mostly terrestrial, but its diet remains uncertain, as none of the suggested preys fully explains the anatomical adaptations and relative abundance of this species.