英文原文
A Rhinocerotid Skull Cooked-to-Death in a 9.2 Ma-Old Ignimbrite Flow of Turkey
References
Pierre-Olivier Antoine1*, Maeva J. Orliac1,2, Gokhan Atici3, Inan Ulusoy4, Erdal Sen4, H. Evren Çubukçu4, Ebru Albayrak5, Neşe Oyal5, Erkan Aydar4, Sevket Sen6
1 Institut des Sciences de l’Évolution, UMR-CNRS 5554, CC064, Université Montpellier 2, Montpellier, France, 2 Department of African Zoology, Royal Museum for Central Africa, Tervuren, Belgium, 3 Department of Geology, General Directorate of MTA, Ankara, Turkey, 4 Hacettepe University Department of Geological Engineering, Beytepe, Ankara, Turkey, 5 General Directorate of MTA, Natural History Museum, Balgat, Ankara, Turkey, 6 Centre de Recherche sur la Paléobiodiversité et les Paléoenvironnements, Muséum National d’Histoire Naturelle, CNRS-UMR 7207, Paris, France
Abstract Top
Background
Preservation of fossil vertebrates in volcanic rocks is extremely rare. An articulated skull (cranium and mandible) of a rhinoceros was found in a 9.2±0.1 Ma-old ignimbrite of Cappadocia, Central Turkey. The unusual aspect of the preserved hard tissues of the skull (rough bone surface and brittle dentine) allows suspecting a peri-mortem exposure to a heating source.
Methodology/Principal Findings
Here we describe and identify the skull as belonging to the large two-horned rhinocerotine Ceratotherium neumayri, well-known in the late Miocene of the Eastern Mediterranean Province. Gross structural features and microscopic changes of hard tissues (bones and teeth) are then monitored and compared to the results of forensic and archaeological studies and experiments focusing on heating effects, in order to reconstruct the hypothetical peri-mortem conditions. Macroscopic and microscopic structural changes on compact bones (canaliculi and lamellae vanished), as well as partial dentine/cementum disintegration, drastic enamel-dentine disjunctions or microscopic cracks affecting all hard dental tissues (enamel, cementum, and dentine) point to continued exposures to temperatures around 400–450°C. Comparison to other cases of preservation of fossil vertebrates within volcanic rocks points unambiguously to some similarity with the 79 AD Plinian eruption of the Vesuvius, in Italy.
Conclusions/Significance
A 9.2±0.1 Ma-old pyroclastic density current, sourced from the Çardak caldera, likely provoked the instant death of the Karacaşar rhino, before the body of the latter experienced severe dehydration (leading to the wide and sustainable opening of the mouth), was then dismembered within the pyroclastic flow of subaerial origin, the skull being separated from the remnant body and baked under a temperature approximating 400°C, then transported northward, rolled, and trapped in disarray into that pyroclastic flow forming the pinkish Kavak-4 ignimbrite ~30 km North from the upper Miocene vent.