Post on 12-Nov-2014
description
This work shows an interesting osteological record found at Sima de Abraham (Sierra Alcaide, Priego de Córdoba). This deposit is characterized by a prominent accumulation of mammalian remains
that include carnivores, specially ursids, in which this work is focused. Some vestiges of others carnivores, such as lynx, wild cat and spotted hyena, show a lower proportion, with almost one element
for each species. Other taxa are artiodactyls (deer and ibex) and microvertebrates such as snakes, rodents (water vole) and lagomorphs (Martínez et Alii 2010). The bone assemblage studied just
composes 135 elements, obtained after a brief archaeological work in the summer of 2008 restricted to calculate the site potential and to avoid damage to the remains of surface.
The cavity corresponds substantially to a sinkhole of vertical development, hidden until its discovery by speleologists from group G 40 of Priego de Córdoba in late 2007. The site is located in Sierra
Alcaide, in the southeastern edge of Cabra massif located in the south of the province of Córdoba, which belongs to the Subbaetic Range, a mountain chain in central Andalusia (Iberia). Lithologic
background corresponds to Mesozoic limestones and dolomites subjected to karst dissolution and strongly influenced by bedding planes, fissures and joints.
The osteological record found was distributed in different locations (contexts) on the lower galleries, mainly represented by the called "Bear´s Hall" reached through the "Bear´s Sinkhole". In turn, these
contexts are integrated in four groups (A, B, C and D) where the A letter, represents to a vertical stratified section composed by clays rich in fossil remains, which contains the contexts 10, 11 and 14
(see Lower Galleries, specially Section A- A´).
AMS dating (Beta-295802 and Beta- 295801) on two deer teeth from the 10 and 14 contexts, point to the second half of the Late Pleistocene, specifically between 40 and 30 ka BP (Table 1).
The influence of the human activities on this bone assemblage does not appear as the main agent of the accumulation; nevertheless, it will probably be the result of accidental falls and perhaps some
ocasional carnivores contributions, frecuently observed in pitfalls cavities and sinkholes trap. However it has been observed a series of cut-marks on the articular cavity of a great bear proximal ulna,
which is interesting as a discrete evidence of some interaction between bears and humans.
MNE of A Group (Contexts 10, 11 and 14)
The bear is the carnivore best represented in the cave, with 18 remains -the most from the apendicular skeleton-, corresponding to 16 skeletal elements (MNE). The minimal number of individuals (MNI) is 3, of which 2 are adults and 1 is juvenile. All remains have been assigned to the species Ursus arctos, based on their morphological and biometrical characters. However, at first, several bones had arisen some doubts because they show a morphology or a size more common for the cave bear (Ursus spelaeus), the only another species of ursid contemporary which lived in the Iberian Peninsula.
Mandible 11/104 (group A) It shows some typical characters of U. arctos, such a coronoid crest with convex profile in the whole length and a small and sharp apophysis on the insertion area of the internal pterygoid. Moreover the morphological and metrical characters of the fourth premolar, first and second molars are clearly of U. arctos. With regard to the osteometry, this bone falls well in the variability of U. arctos, specifically, in that of a big male (left figure).
Ulna 12/118 (group C) It shows osteometric values at the upper limit of the arctoid species variability, corresponding to the medium values for U. spelaeus (right figure, above). However, the length of the ulna is unknown so it makes difficult to distinguish between both species. On the other hand, it has some typical morphological characters of the brown bear: a remarkable curvature of the diaphysis to the medial side, an insertion area for the biceps and braquial muscles occupied by a deep hollow and a hook-shaped prominence on the back of the olecranon larger than in U. spelaeus.
Humerus 11/116 (group A) Although it is a bone with an almost adult size, it is immature yet, so we must be cautious in our conclusions. It shows a mixture of characters of U. arctos and U. spelaeus: the lateral epicondyle crest shows a regular convexity in the whole length, like in U. spelaeus; on the contrary, the humeral crest shows a morphology and a development according to U. arctos. With regard to the osteometry, the relation between the transverse diameter of the distal extremity and the total length (reconstructed) suggests a clear attribution to U. arctos. Two tibias: 11/111 (groups A and B) and 13/121 (group C) Both show a big size, but their morphological and biometrical characters are typical of the U. arctos, being a bone more slender than the one in cave bear (right figure, below). *Osteometric values of U. arctos and U. spelaeus obtained from Torres (1988).
The big size of the ulna, the two tibias and the mandible point to the two adult individuals would be two males of brown bear, one of them with a big size. Moreover, several bones show characteristics of an old individual: articular areas between tibia and fibula fused, a mandible with a heavy dental wear and a callus on the position of the alveolus of the first premolar and a strong exostosis in a thoracic vertebra. An interesting thing is the appearance of cut-marks on the ulna 12/118, specifically on the articular surface with the humerus, maybe to dissect the ligaments which join it to the humeral trochlea.
REMARKABLE SKELETAL REMAINS
THE BEAR FROM SIMA DE ABRAHAM
60
70
80
90
100
110
120
200 250 300 350
5
1
U. spelaeus U. arctos
tibia 111-8 tibia 121
Lineal (U. spelaeus) Lineal (U. arctos)
MARTÍNEZ SÁNCHEZ, Rafael María*, LÓPEZ-GARCÍA, Juan Manuel**, ALCALÁ ORTÍZ, Antonio***, BLAIN, Hugues- Alexandre**, BRETONES GARCÍA, Maria Dolores*, RABAL-GARCÉS, Raquel˚, RODRIGUEZ-VIDAL, Joaquin˚˚, MARTíNEZ-AGUIRRE, Arancha˚˚˚ *) Área de Prehistoria. Departamento de Geografía y Ciencias del Territorio, Universidad de Córdoba. Plaza del Hospital del Cardenal Salazar, 3. 14003 Córdoba. martsancho@gmail.com; lolabre@hotmail.com. **) Institut Català de Paleoecologia Humana i Evolució Social (IPHES), Universitat Rovira i Virgili (URV), Campus Catalunya, Avinguda Catalunya 35, 43003 Tarragona, Spain. e-mail: jmlopez@iphes.cat; hablain@iphes.cat. ***) Grupo Espeleológico G40. Carrera de las monjas, 6- 1. 14800 Priego de Córdoba, Spain. g40espeleo@yahoo.es ˚) Área de Paleontología, Departamento de Ciencias de la Tierra, Facultad de Ciencias, Universidad de Zaragoza. C/ Pedro Cerbuna 12, 50009 Zaragoza, Spain. rrabal@unizar.es ˚˚) Departamento de Geodinámica y Paleontología. Facultad de Ciencias Experimentales, Campus del Carmen. Universidad de Huelva, 21071 Huelva. Spain. jrvidal@uhu.es. ˚˚˚) Departamento de Física Aplicada I, EUITA, Universidad de Sevilla. Ctra. de Utrera km 1, 41013 Sevilla. arancha@us.es.
Field code and reference Lab. code Sample
material
∂ 13 C‰ 14C Age (yr BP) Calibrated yr BP
IntCal09 (2σ)
PC1101 (C- 10 nº 88) Beta-295801 tooth -20.5 35,390±280 39,640–41,280
PC1102 (C- 14 nº 127) Beta-295802 tooth -19.7 25,310±130 29,620–30,450
Bone Side LSD LC-M LSPM LtM1 HmdP HmdM
Mandible R 88 98 60 27 42.5 55.3
Tooth Side Length Breadth - - - -
P₂ R 16.8 13 - - - -
P₃ R 23.5 17.5 - - - -
P₄ R 23.1 15.5 - - - -
M₁ R 31.4 14 - - - -
Low canine R 16.5 12.6 - - - -
LSD: length of the cheektooth row, M₁- P₂ measured along the alveoli
LC- M: length from the aboral border of the alveolus of M₁- aboral border of the canine alveolus
LSPM: length of the premolar row, P₂- P₄, measured along the alveoli
LtM1: length of the edge of M₁
HmdP: Height of the mandible behind P₄
HmdM: Height of the mandible behind aboral border of M₁
Tibia
Osteometric data of spotted hyena jaw (nº 105, Context 11)
AMS DATA
Ulna Mandible
Bibliography:
Martínez Sánchez. R. Mª; López- García, J. M.; Alcalá Ortiz, A.; Blain, H.- A.; Bretones García, Mª D. 2010: “Sima de Abraham (Zagrilla Alta, Priego de Córdoba). Avance a un nuevo yacimiento
paleontológico del Pleistoceno Superior en medio kárstico”. Antiqvitas 22, 5- 20.
Torres, T. 1988: “Osos (Mammalia, Carnivora, Ursidae) del Pleistoceno de la Península Ibérica”. Publicaciones especiales del Boletín Geológico y Minero de España, Special Publication 99, 1–314.