A cautionary note on the use of captive carnivores to model wild predator behavior: a comparison of bone modification patterns on long bones by captive and wild lions

A study with wild lions in Tarangire National Park (Tanzania) and with captive lions in Cabárceno Reserve (Spain) has yielded two different bone modification patterns, probably as a result of the differences in environmental contexts. Captive lions have modified bones more intensively, both in the form of total number of tooth-marked bones and number of tooth marks per tooth-marked bone, probably because of stereotypic behaviors. This emphasizes the importance of environmental contexts to understand carnivore behavior and their resulting bone modification patterns. It also shows that analogical models based on experiments carried out with captive carnivores may be biased and inadequate as proxies for wild carnivore bone modification behaviors.     

Three statistical methods for sex determination in extant and fossil caprines: assessment of the Rupicapra long bones

Sex determination of fossil remains in archeopaleontological contexts is a necessary step in order to gain insights in archaeological and paleobiological parameters such as prey selection and sexual dimorphism. Species with higher sexual dimorphism are more reliably sexed while the sex determination of less dimorphic animals is not attempted. In this study, we compared the accuracy of three different methods in the sex determination of a modern known-sex sample of chamois (Rupicapra pyrenaica parva) from the Cantabrian range (Northern Iberian Peninsula), which is a small-sized ungulate with low sexual dimorphism when compared to other animals in which sex determination has been attempted (i.e., Ursus spelaeus, Capra pyrenaica). The three methods applied were mixture analysis (MA), cluster analysis (CA) and principal component analysis (PCA). Within CA we applied three different analysis: one agglomerative hierarchical method (AH) and two optimal partitioning methods (k-means and robust k-means); and within PCA we applied normal and robust variants of the analysis.     

FOCUS: on the use of the petrous bone for estimating cranial abundance in fossil assemblages

Low representation of braincase bones in zooarchaeological assemblages suggests that skulls have been intensively processed by Levantine Epipalaeolithic foragers; most cranial elements are often unidentifiable and are considered poor candidates for quantifying crania. In contrast, the petrous bone is usually found complete, and was found to be easily identifiable to body size category. Use of the petrous bone in fossil assemblages analyses leads to better estimation of the occurrence of cranial elements, and thus of skeletal part representation. We therefore suggest use of the petrous bone for detecting bone destruction and selective transport in faunal assemblages.     

Testing heterogeneity in faunal assemblages from archaeological sites. Tumbling and trampling experiments at the early-Middle Pleistocene site of Gesher Benot Ya’aqov (Israel)

The current paper reports an experimental case study to test the heterogeneity of faunal assemblages from the Early-Middle Pleistocene Layers V-5 and V-6 of the Gesher Benot Ya’aqov Acheulian site (Israel). Tumbling and trampling experiments were initiated to gain qualitative insight into processes of bone modification and to assess the timing of the biostratonomic chronology, as it was assumed that both mechanisms were responsible for the formation of striations documented on the bone surfaces from the site. The tumbling experiments mimicked sediment movement in a calm lacustrine shoreline environment whereas the trampling experiments investigate the role of animal/hominin activities in dry, muddy and wet environments. Models for the internal operational sequence of an abrasional process due to uni- and multidirectional water movement and of a trampling scenario are presented. These models are used for the interpretation of the fauna from Gesher Benot Ya’aqov.     

Assessing the variability in taphonomic studies of modern leporid remains from Eagle Owl (Bubo bubo) nest assemblages: the importance of age of prey

The Eagle Owl (Bubo bubo) is an important leporid remains accumulator at archaeological sites. Taphonomical studies of modern leporid remains from nest assemblages of this nocturnal raptor aim to establish the main characteristics that define the taphonomic signature of Eagle Owls in order to distinguish them from that of other leporid predators, namely diurnal raptors, terrestrial carnivores and humans. However, analyses carried out so far have shown that the identification of diagnostic features of Eagle Owls leporid nest accumulations is not a straightforward issue – variability has been observed. Age and size of prey are pointed among others as accountable factors but little research has been done on the study of these variables. Here we present the analysis of two samples of modern leporid remains recovered from Eagle Owls nests with the aim of contributing new data to this subject. The high presence of juvenile individuals in both samples enables us to assess anatomical representation, breakage and digestion patterns of immature leporid remains and also to compare them with other assemblages richer in adult prey. Results show that the main characteristic features noted in previous works which recognise Eagle Owls as agents of leporid bones accumulations in the fossil record, are not significantly affected by the age of prey. Less variability than originally thought occurs which means other variables need to be further investigated.     

Autochthony and orientation patterns in Olduvai Bed I: a re-examination of the status of post-depositional biasing of archaeological assemblages from FLK North (FLKN)

Recent excavations at FLK North (Olduvai Gorge, Tanzania) have produced new information on the orientation of archaeological materials at various levels of the site. This information includes the uniform distribution of material azimuths, which contrasts with previous inferences of highly patterned orientations of materials in the Bed I archaeological sites. Those previous inferences of patterned material orientations are based on Mary Leakey's 50-year-old drawings of artifact and fossil bone distribution, but are not verified by our precise measurements of archaeological objects made in situ. Nor do those previous results agree with the general lack of geological, geomorphological, and/or taphonomic data that would indicate significant post-depositional movement of archaeological materials in the sites. We argue here that Leakey's drawings are incomplete (only portions of each assemblage were drawn) and inaccurate in their representation of the original locations, shapes and orientations of most archaeological specimens. This argument is supported by several important mismatches in object representations between a photograph taken of a small portion of the FLK 22 Zinjanthropus site floor before the removal of the archaeological items, and the sketch of the same area drawn by Leakey. Thus, we conclude that primary orientation data of excavations (i.e., direct measurements taken from items) generated prior to object removal are the only valid indicators of the relative isotropy or anisotropy of these important paleoanthropological assemblages.     

What goes in does not always come out: The impact of the ruminant digestive system of sheep on plant material,and its importance for the interpretation of dung-derived archaeobotanical assemblages

Abstract

On archaeological sites where livestock dung was a major fuel source, plant material that survives digestion intact may well be preserved in the remnants of dung-fuelled fires. Preserved plant remains which were derived from dung relate to the diet of animals, and thus provide a way of investigating the agro-pastoral economies of the past. In order to improve our understanding of the taphonomic processes to which plant material is exposed to during digestion, we applied archaeobotanical methods to the analysis of dung from sheep fed a known diet of cereal and wild plant material. Two clear patterns emerge from these investigations. First, cereal material (grain or chaff) survives digestion poorly and was rarely found in the dung analysed. Second, large proportions of seeds of various wild species survive digestion in an identifiable form, probably due to their small size and/or protective coating. These findings are crucial for reliable interpretation of dung-derived plant material in archaeological settings.     

Differentiating bamboo from stone tool cut marks in the zooarchaeological record,with a discussion on the use of bamboo knives

The archaeological record of Southeast Asia is marked by a relative lack of Acheulian assemblages compared with the rest of the Old World. Suggestions that prehistoric human populations in this area relied instead on a non-lithic technology based on bamboo have not been supported by archaeological evidence. To provide a diagnostic means of assessing prehistoric use of bamboo, cut marks were experimentally produced on bone using chert tools and bamboo knives. A scanning electron microscope (SEM) examination revealed morphological differences in cut marks produced by the two materials that allow identification of bamboo knife cut marks on faunal materials. Such evidence, if found in Pleistocene through early Holocene archaeological sites in Southeast Asia, would indicate early human reliance on bamboo technology.     

Effects of distance from stone source on landscape-scale variation in Oldowan artifact assemblages in the Paleo-Olduvai Basin,Tanzania

Ongoing excavations at Olduvai Gorge, Tanzania, reveal tremendous variability among stone artifact assemblages across the Plio-Pleistocene Olduvai Lake Basin during Bed I and lower Bed II times. Theoretically, stone artifact traces of Oldowan hominin land use are determined by the distribution of larger mammal carcasses and arboreal refuge from predation as well as proximity to stone material sources.     

An Osteometric Study on the Variation in Orientation of the Lesser Trochanter in an Early Medieval Human Skeletal Assemblage and Comparison with an Individual from the Late Upper Palaeolithic

Anatomical textbooks describe the lesser trochanter in contemporary humans as being oriented posteromedially. In contrast, orientation of the lesser trochanter towards posterior was observed in some human femora from the Upper Palaeolithic, including the femur of a young adult individual from Germany (Irlich 1), radiocarbon dated to 12 500–11 200 bp (calibrated AMS age). The present study analysed the orientation of the lesser trochanter in femora originating from an early medieval skeletal assemblage (Greding, Germany) and compared the results with those for the Irlich 1 femur. Eleven landmarks, four on the proximal femur, four on the mid‐shaft and three on the distal femur, were recorded with a MicroScribe® digitizer and analysed using AutoCAD® 2010 software. Seven angles and five distances were measured. In the Greding femora, significant differences (p  < 0.05) between sexes were found for several linear measurements, while no significant sex‐related differences existed for angular measurements. For some angular variables related to the orientation of the lesser trochanter, the values for the Irlich 1 femur lay outside the range of variation of the Greding specimens, reflecting the more posterior orientation of the lesser trochanter in the Irlich 1 femur. This posterior orientation of the lesser trochanter was not associated with a particularly low degree of femoral anteversion. It is hypothesised that the differences in orientation of the lesser trochanter between the Irlich 1 femur (and other femora of Upper Palaeolithic individuals) and the femora from Greding could basically reflect differences in traction exercised by the iliopsoas muscle during infancy and childhood between the sedentary agricultural population from Greding and Upper Palaeolithic hunter‐gatherers with a mobile lifestyle. Copyright © 2017 John Wiley & Sons, Ltd.