Variation in tooth mark frequencies on long bones from the assemblages of all three extant bone-collecting hyaenids

Tooth mark frequencies on long bones are examined from the assemblages of all three extant bone-collecting hyaenids. Comparisons are made with a recent study examining tooth mark frequencies and possible sources of variation from a single spotted hyaena (Crocuta crocuta) assemblage (Faith, J.T., 2007. Sources of variation in carnivore tooth-mark frequencies in a modern spotted hyena (Crocuta crocuta) den assemblage, Amboseli Park, Kenya. Journal of Archaeological Science 34 (10), 1601–1609). The factors that may influence tooth mark frequencies are fragment size, fragments from different sized animals, region of skeletal element and bone density. All four factors are examined in the present study and compared across species and with previous results. The results indicate that there is a great deal of variation in tooth mark frequencies not only between the species but also from the same species.     

Developmental defects and postmortem changes in archaeological pig teeth from Fais Island,Micronesia

The study investigated developmental defects of the dental hard tissues and postmortem changes in archaeological pig molars from Fais Island, Micronesia. The developmental defects of enamel were indicative of a disturbance of the secretory stage (accentuation of the incremental pattern, occurrence of Wilson bands and of hypoplastic defects) and the maturation stage of amelogenesis (hypomineralisation). Presence of coronal cementum in an M₃ indicated a partial premature breakdown of the reduced enamel epithelium or a partial demise of the enamel organ earlier during tooth development. Developmental defects of dentine presented as accentuated Andresen lines and areas of interglobular dentine. The pattern of developmental defects in the studied molars and the fact that deciduous premolars of the pigs from Fais did not exhibit developmental defects on macroscopic inspection are consistent with the hypothesis that the tooth defects were caused by periods of severe nutritional stress occurring after weaning. Postmortem changes caused by microbial infiltration were recorded in dentine and cementum. A presumed case of soft tissue preservation in the form of presence of odontoblast processes was observed in an M¹.     

Taphonomy of the bones of rodents consumed by Andean hog-nosed skunks (Conepatus chinga, Carnivora,Mephitidae) in central Argentina

The Andean hog-nosed skunks (Conepatus chinga) are generalized consumers. Rodents are a substantial part of their diet. In order to learn about the effects of this predator on the bones of the prey they consume, the bone remains from scats collected in La Pampa, Argentina, were analyzed from a taphonomic point of view. Analysis confirms that C. chinga produces severe destruction of bone remains, mainly during the chewing process. This allows inclusion of this predator in the category of extreme modifier of the bones of its prey. Data presented here and their interpretation provide criteria to identify the intervention of this predator in archaeological and paleontological sites.     

A note on the use of temporal frequency distributions in studies of prehistoric demography

Temporal frequency distributions of archaeological sites and radiocarbon dates are commonly used as proxies for prehistoric population levels based on the assumption that more people create a stronger archaeological signal. While this assumption is certainly correct, we question whether relative frequencies of sites or dates observed from prehistoric contexts are necessarily linked to human demography. In this paper, we demonstrate that the typical positive curvilinear frequency distributions observed in archaeological contexts also regularly occur in paleontological and geological contexts and are thus likely caused by the operation of time-dependent destructive processes, what we call “taphonomic bias.” Using a simple model, which assumes a constant rate of site loss over time, we show how taphonomic bias can produce positive curvilinear frequency distributions through time even in cases of population stasis, decline, and fluctuation. We conclude that caution must be used when attempting to infer demographic trends from frequency distributions alone.     

Dietary Stress and Animal Resource Use at the Postclassic Maya city,Mayapán (Mexico)

ABSTRACT

Environmental changes resulting in drought and reductions in the availability of animal resources during the Late Classic Maya have been linked with the Maya ‘collapse’. Decreases in availability of dietary staples such as artiodactyls, and particularly white-tailed deer, during the Late Classic period would have placed food stress on populations during later periods. To test this hypothesis, here bone breakage patterns are examined at the Postclassic Maya city, Mayapán, to assess whether artiodactyl bones were being intensively processed for bone fats (marrow and grease). Fragmentation morphology, size and surface markings, along with skeletal part representation and distribution of large mammal bones were recorded for bone assemblages from several houselots. Evidence suggests the Maya were likely utilising bone marrow from artiodactyls but not intensively and they were not extracting bone grease. These results indicate that decreased accessibility to artiodactyls during the Postclassic was not causing high levels of dietary stress for the Maya at Mayapán, which is consistent with recent evidence demonstrating dietary consistency during the Postclassic in northern Yucatan.     

Phytolith taphonomy: a comparison of dry ashing and acid extraction on the breakdown of conjoined phytoliths formed in Triticum durum

Durum wheat plants grown under optimum irrigation conditions in Jordan were processed in three different ways: 1) using a dry ashing method, 2) using acid extraction and 3) using both these methods, first dry ashing and then acid extraction. The aim was to determine if the laboratory processing method employed has an impact on the number of conjoined phytoliths recovered. This is important because it has been proposed that the number of conjoined phytoliths, or multi cells, can be an indication of water availability in arid and semi-arid regions (Rosen and Weiner 1994). The results showed that the processing method does have an impact on the resulting assemblage, with dry ashing producing a greater number of multi-cells than acid extraction. It is proposed that either the more violent oxidation of organic matter during acid extraction causes the breakup of conjoined phytoliths, or that the silica dehydrates during dry ashing resulting in a slight fusion between the individual phytoliths and hence more conjoined forms.     

How many bones make five? The art and science of guesstimation in archaeozoology

Six faunal statistics are described and assessed by means of simulation. Of these, the ‘probable number of individuals’ (PNI) methods, which include the Lincoln and Krantz indices, are shown to perform remarkably well. The assumptions of these PNI procedures are given and circumstances under which PNI methods can be employed are described. Palaeoeconomic methods occupy a middle ground between classical statistical theory and experimental archaeology, hence the use of the term ‘guesstimation’: this ground is explored and it is shown that these methods can have a considerable bearing on the interpretation of taphonomic and ‘spatial’ (intra-stratum) regularities. Promising avenues for future research are indicated.     

Critical reassessment of putative Acheulean Porosphaera globularis beads

Excavations at Acheulean sites in northern Europe at the end of the 19th century have yielded fossil sponges belonging to the Late Cretaceous species Porosphaera globularis. The spherical morphology of these fossils, their small size, and the presence of a natural complete perforation in their center have led some archaeologists to interpret them as the oldest known beads. Others argue that the presence of these fossils at archaeological sites is due to natural processes. Re-examination of material collected during the 19th century has recently revived the bead interpretation. We tested the bead hypothesis by analyzing 13 samples of Porosphaera from nine sites in Britain and France. We conducted morphometric and microscopic analyses on specimens recovered from archaeological sites (n = 349), a natural geological sample, which was collected directly from Cretaceous strata (n = 352), and a sample from a Bronze Age burial (n = 43). Reappraisal of contextual data shows that the association of these finds with Acheulean artifacts is uncertain. Our results show that archaeological specimens are significantly different in size and perforation pattern from those of the natural geological sample. This may be due to size-sorting caused by sedimentary processes, size-selection by Palaeolithic people or by 19th century collectors. Modifications of the fossils' natural shape were detected on a few specimens in the form of localized abrasions and microchipping along the hole margins. A single specimen displays a facet close to the hole produced by grinding. The surfaces of these features exhibit a hue lighter than that observed on the remainder of the specimens indicating that they may be recent in origin and due to post-excavation and preservation treatment. However, this seems contradicted, for some specimens from Bedford, by the fact that according to Smith, W.G. [1884. On a Palaeolithic floor at North-East London. Journal of the Anthropological Institute of Great Britain and Ireland 13, 357–384] the specimens bearing microchipping and abrasions were found by him and “not touched or manipulated by the workmen”. We conclude that new excavations of these sites, involving systematic screening of sediments, are needed in order to attempt to solve the Porosphaera “mystery”.     

Mixed occupation during the Middle Palaeolithic: Case study of a small pit-cave-site of Les Pêcheurs (Ardèche,south-eastern France)

The Pêcheurs cave is a unique example of a Middle Palaeolithic site with three kinds of accumulations: (1) ibex that died in a natural trap, (2) carnivores that died within the cavity, and, (3) a series of short-term occupations by humans who left a few artifacts and a hearth area. Biological patterns of ibex remains (skeletal parts, age) show a homogeneous structure, related to natural death inside the cave. The Chassezac valley is narrow and sinuous, bordered by steep cliffs occupied by well-adapted hoofed-species (Caprinae). Moreover, Les Pêcheurs is a shallow cave, pit-like, and in its deepest part (Sector 4) provided both man and animals with shelter. The presence of a fire place (in the middle of the sequence of Sector 4) firmly indicates the presence of an in situ occupation by a small group of hominids. According to the stratigraphical patterns and the analysis of the lithic assemblages, artifacts do not seem to have been introduced into sediments. The lithic assemblages (technically homogeneous) indicate that small mobile human groups inhabited a cave that offered, by virtue of its morphology, a natural shelter against the cold winds blowing in the Chassezac valley and the plateaus of the south-eastern borders of the Massif Central Mountains. The exploitation of biotopes such as this rocky area constitutes a specific case of human subsistence behavior and settlement strategy. The deepest layer is characterized by a lithic assemblage mostly made of local raw material (quartz) implying a low investment in lithic production. Few flakes made from non-local flints attest to the mobility of the human occupants who moved across these areas and perhaps found in the valleys, short-term refuge.     

Neurocranial abnormalities of the Gongwangling Homo erectus from Lantian,China

The Homo erectus cranium found at Gongwangling, near Lantian, China, and dated to ≈1.2 ma BP has been analyzed with respect to its evolutionary position. However, the remains, and especially the internal and external surfaces of the neurocranium, present a series of marked abnormalities. These irregularities consist principally of a pronounced cresting and scalloping of the external surface of the frontal bone and anterior parietal bone and a similar alteration of the internal surface of a mid transverse section of parietal bone that connects with the fossilization break across the anterior parietal bone. There is no obvious exposure of diploë on the surfaces. Woo (Vertebrata PalAsiatica 10:1–16, 1966) briefly ascribed these abnormalities to postmortem erosion, and Caspari (Am. J. Phys. Anthropol. 102:565–568, 1997) has attributed the irregularities of the right supraorbital torus to antemortem trauma. It has been suggested that the pervasive neurocranial alterations might be pathological. Computerized tomography (CT) analysis of the frontal and parietal bones revealed complete radiopacity of the anterior half of the fossil; it is possible to distinguish large frontal sinuses but other details, including in the area of the purported traumatic lesion, are invisible. However, in the posterior frontal bone and preserved portions of the parietal bone the diploë and tables are discernible. Externally on the frontoparietal section and internally on the transverse parietal piece, there are clear erosional lacunae in the associated table, combined with a thin layer of matrix which obscures the eroded diploë externally. The superficial irregularities are therefore due to postmortem taphonomic alterations of the bone and not pathological processes. In addition, it is apparent that the two pieces were embedded in the matrix at different angles, resulting in their differential erosion.