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Childhood is an ontogenetic stage unique to the modern human life history pattern. It enables the still dependent infants to achieve an extended rapid brain growth, slow somatic maturation, while benefitting from provisioning, transitional feeding, and protection from other group members. This tipping point in the evolution of human ontogeny likely emerged from early Homo. The GAR IVE hemi-mandible (1.8 Ma, Melka Kunture, Ethiopia) represents one of the rarely preserved early Homo infants (~ 3 years at death), recovered in a richly documented Oldowan archaeological context. Yet, based on the sole external inspection of its teeth, GAR IVE was diagnosed with a rare genetic disease–amelogenesis imperfecta (AI)–altering enamel. Since it may have impacted the child's survival, this diagnosis deserves deeper examination. Here, we reassess and refute this diagnosis and all associated interpretations, using an unprecedented multidisciplinary approach combining an in-depth analysis of GAR IVE (synchrotron imaging) and associated fauna. Some of the traits previously considered as diagnostic of AI can be better explained by normal growth or taphonomy, which calls for caution when diagnosing pathologies on fossils. We compare GAR IVE's dental development to other fossil hominins, and discuss the implications for the emergence of childhood in early Homo. [ABSTRACT FROM AUTHOR]

Melka Kunture on the highlands of Ethiopia has provided evidence for the early peopling of the Ethiopian highlands (>2000 m asl). At site Garba IV, an Oldowan technocomplex was retrieved in levels E-F located shortly below the base of the Olduvai subchron, with a currently accepted age of 1.925 Ma, while the early Acheulean was found in level D located close to the base of the Olduvai subchron. The base of the Olduvai subchron becomes therefore a prime chronostratigraphic marker for the study of the early peopling of the Ethiopian plateau in the Early Pleistocene. Here we report new magnetostratigraphic data from two sections from the Kella valley located close to Garba IV, namely Kella III bis and Kella Bridge. We document in these sections the occurrence of the Olduvai subchron, confirmed also by 40Ar/39Ar ages from the literature. We correlate these new data to previous data from Garba IV, establishing a robust registry of the critical Olduvai subchron in the lower part of the Middle Succession (part of the former Melka Kunture Formation), spanning altogether from ∼2 Ma to ∼1.2 Ma, and we also point to a regional basal unconformity marking its onset of deposition. The better constrained magnetochronology provides firm evidence that hominins were peopling areas at 2000 m of altitude at least 2 million years ago. • Melka Kunture (Ethiopia) registers the Oldowan-Acheulean transition. • Melka Kunture registers the Brunhes-Jaramillo-Olduvai magnetic polarity sequence. • The early Acheulean technocomplex has interpolated age of 1.95 (−0.025; +0.1) Ma. [ABSTRACT FROM AUTHOR]

We present new magnetostratigraphic results from the Melka Kunture sedimentary sequence outcropping along the Gombore and Garba gullies in the Upper Awash Valley of Ethiopia that provide a new temporal framework for human presence in this area of the Ethiopian plateau in the Pleistocene. We obtained a time-diagnostic sequence of normal and reverse polarity magnetozones representing a relatively continuous magnetochronologic record extending from the Brunhes Chron at the top to the Olduvai Subchron or possibly the Reunion Subchron at the base, assembled from 9 stratigraphic sections correlated in a regional lithostratigraphic context. By integrating our chronology provided by paleomagnetism with 40Ar/39Ar dating from the literature, we generated simple yet reliable and testable age models of deposition for the Melka Kunture sedimentary sequence that we used to estimate the mean ages of the main archeological levels therein contained that resulted ranging from ∼0.6 Ma to ∼2.1 Ma thus representing altogether one of the most persistent and prolonged records of human presence of the entire African continent. • Magnetostratigraphy reveals that the Melka Kunture stratigraphy extends in substantial continuity from the Brunhes Chron to the Olduvai Subchron. • Age models of deposition based on magnetochronology and geochronology reveal that the sequence deposited from ∼0.6 to ∼2.1 Ma. • All main archeological levels in the Melka Kunture stratigraphy have been assigned numerical age estimates with errors. • Melka Kunture represents one of the most extended - and now dated - records of human presence in Africa in the Pleistocene. [ABSTRACT FROM AUTHOR]

New ichnological data are available at the prehistoric site of Melka Kunture, Upper Awash Valley in Ethiopia. Excavation of new test pits enabled us to explore the volcanic and fluvio-lacustrine sequence at the Gombore II Open Air Museum archaeological site (ca. 0.85 Ma). This has allowed a detailed reconstruction of the palaeoenvironment and of the fauna present in the time interval between 1.2 and 0.85 Ma. Various-sized mammals, birds, molluscs as well as hominins left tracks throughout the sequence, and document a varied fauna and associated behaviours. Most of the hominin tracks were made by young individuals on the basis of size and are some of the earlier child tracks to be reported. The mollusc traces document the presence and orientation of water streams which, according to the associated vertebrate traces, were visited by hominins, mammals and birds. Most of these traces were found within levels traditionally considered barren for archaeology, yet they all document life activity and are always in situ. This confirms the potential of the ichnological research as an important complementary tool for archaeological investigations. Image 1 • New excavations are described within the 1.2/0.85 Ma sequence of Gombore (Ethiopia). • We characterise the recurrent association of fossil footprints, faunal and lithic remains. • Potential hominin footprints are recorded at 1.2, 1.2/0.87 and 0.85 Ma. • Amultidisciplinary approach reconstructs changing environments and biological records. • Hominin and animal palaeoecology and behaviours are evidenced. [ABSTRACT FROM AUTHOR]