Response to Comment on "U-Th dating of carbonate crusts reveals Neandertal origin of Iberian cave art".

Slimak et al challenge the reliability of our oldest (>65,000 years) U-Th dates on carbonates associated with cave paintings in Spain. They cite a supposed lack of parietal art for the 25,000 years following this date, along with potential methodological issues relating to open-system behavior and corrections to detrital or source water 230Th. We show that their criticisms are unfounded.

U-Th dating of carbonate crusts reveals Neandertal origin of Iberian cave art.

The extent and nature of symbolic behavior among Neandertals are obscure. Although evidence for Neandertal body ornamentation has been proposed, all cave painting has been attributed to modern humans. Here we present dating results for three sites in Spain that show that cave art emerged in Iberia substantially earlier than previously thought. Uranium-thorium (U-Th) dates on carbonate crusts overlying paintings provide minimum ages for a red linear motif in La Pasiega (Cantabria), a hand stencil in Maltravieso (Extremadura), and red-painted speleothems in Ardales (Andalucía). Collectively, these results show that cave art in Iberia is older than 64.8 thousand years (ka). This cave art is the earliest dated so far and predates, by at least 20 ka, the arrival of modern humans in Europe, which implies Neandertal authorship.

An early modern human presence in Sumatra 73,000-63,000 years ago.

Genetic evidence for anatomically modern humans (AMH) out of Africa before 75 thousand years ago (ka) and in island southeast Asia (ISEA) before 60 ka (93-61 ka) predates accepted archaeological records of occupation in the region. Claims that AMH arrived in ISEA before 60 ka (ref. 4) have been supported only by equivocal or non-skeletal evidence. AMH evidence from this period is rare and lacks robust chronologies owing to a lack of direct dating applications, poor preservation and/or excavation strategies and questionable taxonomic identifications. Lida Ajer is a Sumatran Pleistocene cave with a rich rainforest fauna associated with fossil human teeth. The importance of the site is unclear owing to unsupported taxonomic identification of these fossils and uncertainties regarding the age of the deposit, therefore it is rarely considered in models of human dispersal. Here we reinvestigate Lida Ajer to identify the teeth confidently and establish a robust chronology using an integrated dating approach. Using enamel-dentine junction morphology, enamel thickness and comparative morphology, we show that the teeth are unequivocally AMH. Luminescence and uranium-series techniques applied to bone-bearing sediments and speleothems, and coupled uranium-series and electron spin resonance dating of mammalian teeth, place modern humans in Sumatra between 73 and 63 ka. This age is consistent with biostratigraphic estimations, palaeoclimate and sea-level reconstructions, and genetic evidence for a pre-60 ka arrival of AMH into ISEA. Lida Ajer represents, to our knowledge, the earliest evidence of rainforest occupation by AMH, and underscores the importance of reassessing the timing and environmental context of the dispersal of modern humans out of Africa.

U-series dating of Paleolithic art in 11 caves in Spain.

Paleolithic cave art is an exceptional archive of early human symbolic behavior, but because obtaining reliable dates has been difficult, its chronology is still poorly understood after more than a century of study. We present uranium-series disequilibrium dates of calcite deposits overlying or underlying art found in 11 caves, including the United Nations Educational, Scientific, and Cultural Organization (UNESCO) World Heritage sites of Altamira, El Castillo, and Tito Bustillo, Spain. The results demonstrate that the tradition of decorating caves extends back at least to the Early Aurignacian period, with minimum ages of 40.8 thousand years for a red disk, 37.3 thousand years for a hand stencil, and 35.6 thousand years for a claviform-like symbol. These minimum ages reveal either that cave art was a part of the cultural repertoire of the first anatomically modern humans in Europe or that perhaps Neandertals also engaged in painting caves.

Stratigraphic context and direct dating of the Neandertal mandible from Cova del Gegant (Sitges, Barcelona).

Stratigraphic study of the Cova del Gegant's sedimentary fill revealed different cycles of accumulation of typical interior cave and delta facies. A precise chronology for these deposits, the faunal remains and stone tools contained therein was obtained by radiocarbon, U-Th and OSL. Our results indicate that the Upper Pleistocene archaeological sequence dates between 49.3 +/- 1.8 ka BP, the U-Th age of the overlying flowstone, and 60.0 +/- 3.9 ka BP, the OSL age of the basal deposits. We have also directly dated the site's Neandertal mandible to 52.3 +/- 2.3 ka by U-Th.

Hovk 1 and the Middle and Upper Paleolithic of Armenia: a preliminary framework.

The territory of present day Armenia is a geographic contact zone between the Near East and the northern Caucasus. Armenian Middle and Upper Paleolithic records are both few and patchy as a result of the historical paucity of systematic archaeological research in the country. Consequently, it is currently difficult to correlate the Armenian Middle and Upper Paleolithic records with those from other neighboring regions. We present new archaeological and chronometric data (luminescence, U-Th, and 14C) from our ongoing research at Hovk 1 Cave in northeast Armenia. We discuss in particular two activity phases in Hovk 1 Cave for which we have outline chronometric data: (1) an early Middle Paleolithic occupational phase, dated by optically stimulated luminescence (OSL) to 104+/-9.8 ka BP(OSL); and (2) a Paleolithic occupational phase characterized by microlithic flakes dated by AMS 14C to 39,109+/-1,324 calibrated years BP(Hulu). The two phases are separated by a hiatus in hominin occupation corresponding to MIS 4 and an episode in early MIS 3. These chronometric data, taken together with the preliminary paleoenvironmental reconstruction of the Hovk 1 Cave and environment, suggest that these activity phases represent short-lived and seasonal use of the cave presumably by small groups of hunters during episodes of mild climate. Neither tool manufacture nor butchery appears to have taken place within the cave, and consequently, the archaeological record included, for the most part, finished tools and blanks. We address the chronology and techno-typological aspects of Hovk 1 lithics in relation to: (1) the Paleolithic records of Armenia, and (2) the broader interregional context of early Middle Paleolithic hominin occupation and the Middle-Upper Paleolithic transition in the Caucasus.

Late Pleistocene human skull from Hofmeyr, South Africa, and modern human origins.

The lack of Late Pleistocene human fossils from sub-Saharan Africa has limited paleontological testing of competing models of recent human evolution. We have dated a skull from Hofmeyr, South Africa, to 36.2 +/- 3.3 thousand years ago through a combination of optically stimulated luminescence and uranium-series dating methods. The skull is morphologically modern overall but displays some archaic features. Its strongest morphometric affinities are with Upper Paleolithic (UP) Eurasians rather than recent, geographically proximate people. The Hofmeyr cranium is consistent with the hypothesis that UP Eurasians descended from a population that emigrated from sub-Saharan Africa in the Late Pleistocene.