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1.
Sci Rep ; 10(1): 11081, 2020 07 06.
Article in English | MEDLINE | ID: mdl-32632190

ABSTRACT

The recently described site of Kalinga in the Philippines adds to our understanding of Early-Middle Pleistocene hominin behaviour. Yet, disentangling the natural from the anthropogenic modifications that have taken place in such an old archaeological site is challenging. In this paper we use a set of taphonomic tools at hand to rectify the distortion made by natural processes during the formation of the Kalinga site. From the description of the ribs completeness, surface damages and scattering in the excavation, one can reconstruct the butchery, transport and deposition sequence of the rhino carcass and its post-depositional disturbances and diagenetic evolution of the site. We conclude that the rhino and the stone artefacts potentially used to deflesh the carcass were transported by a mudflow from its butchery place over a few meters only and got stuck and mixed with an older faunal assemblage that was transported by a small stream.

2.
Nature ; 557(7704): 233-237, 2018 05.
Article in English | MEDLINE | ID: mdl-29720661

ABSTRACT

Over 60 years ago, stone tools and remains of megafauna were discovered on the Southeast Asian islands of Flores, Sulawesi and Luzon, and a Middle Pleistocene colonization by Homo erectus was initially proposed to have occurred on these islands1-4. However, until the discovery of Homo floresiensis in 2003, claims of the presence of archaic hominins on Wallacean islands were hypothetical owing to the absence of in situ fossils and/or stone artefacts that were excavated from well-documented stratigraphic contexts, or because secure numerical dating methods of these sites were lacking. As a consequence, these claims were generally treated with scepticism 5 . Here we describe the results of recent excavations at Kalinga in the Cagayan Valley of northern Luzon in the Philippines that have yielded 57 stone tools associated with an almost-complete disarticulated skeleton of Rhinoceros philippinensis, which shows clear signs of butchery, together with other fossil fauna remains attributed to stegodon, Philippine brown deer, freshwater turtle and monitor lizard. All finds originate from a clay-rich bone bed that was dated to between 777 and 631 thousand years ago using electron-spin resonance methods that were applied to tooth enamel and fluvial quartz. This evidence pushes back the proven period of colonization 6 of the Philippines by hundreds of thousands of years, and furthermore suggests that early overseas dispersal in Island South East Asia by premodern hominins took place several times during the Early and Middle Pleistocene stages1-4. The Philippines therefore may have had a central role in southward movements into Wallacea, not only of Pleistocene megafauna 7 , but also of archaic hominins.


Subject(s)
Fossils , Hominidae , Tool Use Behavior , Aluminum Silicates , Animal Migration , Animals , Clay , Electron Spin Resonance Spectroscopy , Geologic Sediments , History, Ancient , Philippines , Radiometric Dating
3.
Nature ; 548(7667): 322-325, 2017 08 17.
Article in English | MEDLINE | ID: mdl-28792933

ABSTRACT

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.


Subject(s)
Caves , Fossils , Human Migration/history , Electron Spin Resonance Spectroscopy , History, Ancient , Humans , Indonesia , Luminescence , Rainforest , Tooth/anatomy & histology , Uranium
4.
Nature ; 514(7521): 223-7, 2014 Oct 09.
Article in English | MEDLINE | ID: mdl-25297435

ABSTRACT

Archaeologists have long been puzzled by the appearance in Europe ∼40-35 thousand years (kyr) ago of a rich corpus of sophisticated artworks, including parietal art (that is, paintings, drawings and engravings on immobile rock surfaces) and portable art (for example, carved figurines), and the absence or scarcity of equivalent, well-dated evidence elsewhere, especially along early human migration routes in South Asia and the Far East, including Wallacea and Australia, where modern humans (Homo sapiens) were established by 50 kyr ago. Here, using uranium-series dating of coralloid speleothems directly associated with 12 human hand stencils and two figurative animal depictions from seven cave sites in the Maros karsts of Sulawesi, we show that rock art traditions on this Indonesian island are at least compatible in age with the oldest European art. The earliest dated image from Maros, with a minimum age of 39.9 kyr, is now the oldest known hand stencil in the world. In addition, a painting of a babirusa ('pig-deer') made at least 35.4 kyr ago is among the earliest dated figurative depictions worldwide, if not the earliest one. Among the implications, it can now be demonstrated that humans were producing rock art by ∼40 kyr ago at opposite ends of the Pleistocene Eurasian world.


Subject(s)
Art/history , Caves , Animals , Deer , History, Ancient , Human Activities/history , Indonesia , Swine , Uranium
5.
J Hum Evol ; 57(5): 527-37, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19058833

ABSTRACT

Excavations at Liang Bua, a limestone cave on the island of Flores, East Indonesia, have yielded a well-dated archaeological and faunal sequence spanning the last 95k.yr., major climatic fluctuations, and two human species -H. floresiensis from 95 to 17k.yr.(1), and modern humans from 11k.yr. to the present. The faunal assemblage comprises well-preserved mammal, bird, reptile and mollusc remains, including examples of island gigantism in small mammals and the dwarfing of large taxa. Together with evidence from Early-Middle Pleistocene sites in the Soa Basin, it confirms the long-term isolation, impoverishment, and phylogenetic continuity of the Flores faunal community. The accumulation of Stegodon and Komodo dragon remains at the site in the Pleistocene is attributed to Homo floresiensis, while predatory birds, including an extinct species of owl, were largely responsible for the accumulation of the small vertebrates. The disappearance from the sequence of the two large-bodied, endemic mammals, Stegodon florensis insularis and Homo floresiensis, was associated with a volcanic eruption at 17 ka and precedes the earliest evidence for modern humans, who initiated use of mollusc and shell working, and began to introduce a range of exotic animals to the island. Faunal introductions during the Holocene included the Sulawesi warty pig (Sus celebensis) at about 7ka, followed by the Eurasian pig (Sus scrofa), Long-tailed macaque, Javanese porcupine, and Masked palm civet at about 4ka, and cattle, deer, and horse - possibly by the Portuguese within historic times. The Holocene sequence at the site also documents local faunal extinctions - a result of accelerating human population growth, habitat loss, and over-exploitation.


Subject(s)
Biological Evolution , Fossils , Animals , History, Ancient , Hominidae/classification , Hominidae/genetics , Humans , Phylogeny
6.
J Hum Evol ; 53(6): 709-17, 2007 Dec.
Article in English | MEDLINE | ID: mdl-17706269

ABSTRACT

The Punung Fauna is a key component in the biostratigraphic sequence of Java. It represents the most significant faunal turnover on the island in the last 1.5 million years, when Stegodon and other archaic mammal species characteristic of earlier Faunal stages were replaced by a fully modern fauna that included rainforest-dependent species such as Pongo pygmaeus (orangutan). Here, we report the first numerical ages for the Punung Fauna obtained by luminescence and uranium-series dating of the fossil-bearing deposits and associated flowstones. The Punung Fauna contained in the dated breccia is of early Last Interglacial age (between 128+/-15 and 118+/-3 ka). This result has implications for the age of the preceding Ngandong Fauna, including Homo erectus remains found in the Ngandong Terrace, and for the timing of Homo sapiens arrival in Southeast Asia, in view of claims for a modern human tooth associated with the Punung breccia.


Subject(s)
Biodiversity , Fossils , Animals , Chronology as Topic , Geologic Sediments/analysis , Hominidae , Humans , Indonesia , Tropical Climate
7.
Nature ; 431(7012): 1087-91, 2004 Oct 28.
Article in English | MEDLINE | ID: mdl-15510146

ABSTRACT

Excavations at Liang Bua, a large limestone cave on the island of Flores in eastern Indonesia, have yielded evidence for a population of tiny hominins, sufficiently distinct anatomically to be assigned to a new species, Homo floresiensis. The finds comprise the cranial and some post-cranial remains of one individual, as well as a premolar from another individual in older deposits. Here we describe their context, implications and the remaining archaeological uncertainties. Dating by radiocarbon (14C), luminescence, uranium-series and electron spin resonance (ESR) methods indicates that H. floresiensis existed from before 38,000 years ago (kyr) until at least 18 kyr. Associated deposits contain stone artefacts and animal remains, including Komodo dragon and an endemic, dwarfed species of Stegodon. H. floresiensis originated from an early dispersal of Homo erectus (including specimens referred to as Homo ergaster and Homo georgicus) that reached Flores, and then survived on this island refuge until relatively recently. It overlapped significantly in time with Homo sapiens in the region, but we do not know if or how the two species interacted.


Subject(s)
Archaeology , Biodiversity , Hominidae , Animals , Biological Evolution , Body Constitution , Carbon Radioisotopes , Female , Geography , History, Ancient , Hominidae/classification , Human Activities/history , Humans , Indonesia , Predatory Behavior , Reproducibility of Results , Skeleton , Skull , Time Factors , Tooth
8.
Neuroscience ; 120(1): 133-42, 2003.
Article in English | MEDLINE | ID: mdl-12849747

ABSTRACT

In adult cats, the induction of homonymous binocular central retinal lesions causes a dramatic reorganization of the topographic map in the sensory-deprived region of the primary visual cortex. To investigate the possible involvement of the alpha-subunit of the calcium/calmodulin dependent protein kinase type II (alphaCaMKII) in this form of brain plasticity, we performed in situ hybridization and Western blotting experiments to analyze mRNA, protein and autophosphorylation levels of this multifunctional kinase. No differences in the mRNA or protein levels were observed between the central, sensory-deprived and the peripheral, non-deprived regions of area 17 of retinal lesion animals or between corresponding cortical regions of normal control animals. Western blotting with an alphaCaMKII threonine-286 phosphorylation-state specific antiserum consistently showed a small, albeit not significant, increase of alphaCaMKII autophosphorylation in the central versus the peripheral region of cortical area 17, and this both in normal subjects as well as in retinal lesion animals with a 3-day post-lesion survival time. In contrast, a post-lesion survival time of 14 days resulted in a alphaCaMKII autophosphorylation level that was four times higher in visually-deprived area 17 than in the non-deprived cortical region. This increased phosphorylation state is not a direct consequence of the decrease in visual activity in these neurons, because we would have expected to see a similar change at shorter or longer post-lesion survival times or in the visually deprived visual cortex of animals in which the left optic tract and the corpus callosum were surgically cut. No such changes were observed, leading to the conclusion that the phosphorylation changes observed at 14 days are related to a delayed reorganization of the retinotopic map of the striate cortex.


Subject(s)
Brain Mapping/methods , Neuronal Plasticity/physiology , Protein Serine-Threonine Kinases/biosynthesis , Retina/metabolism , Visual Cortex/metabolism , Animals , Calcium-Calmodulin-Dependent Protein Kinase Kinase , Cats , Gene Expression Regulation, Enzymologic/physiology , Phosphorylation , Protein Serine-Threonine Kinases/analysis , Protein Serine-Threonine Kinases/genetics , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Retina/chemistry , Visual Cortex/chemistry
9.
Gen Comp Endocrinol ; 132(2): 293-303, 2003 Jun 15.
Article in English | MEDLINE | ID: mdl-12812778

ABSTRACT

In the course of producing monoclonal antibodies to turkey prolactin, three monoclonal antibodies to turkey chromogranin A (CgA) were also produced, apparently arising from minor contamination of the turkey prolactin immunogen with peptide fragments of CgA. The identity of the antigen recognized by these antibodies was established by tandem mass spectrometry de novo sequencing of seven tryptic peptides from a turkey pituitary protein purified by immunoaffinity chromatography. These peptides showed high homology with distinctly separate regions of mammalian and ostrich CgA, and in silico cloned chicken CgA sequences. Chromogranin A immunostaining patterns on Western blots and pituitary tissue sections differed from those of prolactin, growth hormone, or luteinizing hormone (LH). Dual-label fluorescent immunohistochemistry revealed that CgA was co-localized with LH in most avian gonadotrophs in young chickens and turkeys, but not in adult, laying birds. Conversely, CgA was found in a majority of somatotrophs in laying birds but was absent from somatotrophs in young, growing chickens and turkeys. Lactotrophs contained no detectable CgA immunoreactivity in the tissues studied. These results suggest that CgA may modulate hormone secretion by gonadotrophs and somatotrophs in a manner that differs between cell type with age or reproductive state.


Subject(s)
Chickens/metabolism , Chromogranins/metabolism , Gonadotropins/metabolism , Growth Hormone/metabolism , Pituitary Gland/metabolism , Turkeys/metabolism , Aging/physiology , Amino Acid Sequence , Animals , Antibodies, Monoclonal/pharmacology , Antibody Specificity , Chromatography, Affinity , Chromogranin A , Chromogranins/chemistry , Chromogranins/immunology , Computer Simulation , Electrophoresis, Polyacrylamide Gel , Fluorescent Antibody Technique , Hybridomas , Immunochemistry , Immunohistochemistry , Isoelectric Focusing , Microscopy, Fluorescence , Molecular Sequence Data , Pituitary Gland/cytology , Pituitary Gland/drug effects , Prolactin/immunology , Reproduction/physiology
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