REGURGITATION PELLETS

Volumen 1 Number 4 Year 2003

2019-11-06T21:34:53+02:00October 26th, 2019|Volumen 1. Number 4. Year 2003.|

VOLUME 1. NUMBER 4. 2003

Structural and Chemical Bone Modifications in a Modern Owl Pellet Assemblage from Olduvai Gorge (Tanzania).

Yannicke Dauphin, Peter Andrews, Christiane Denys, Yolanda Fernández-Jalvo, Terry Williams.

Keywords: BONE, REGURGITATION PELLETS, OLDUVAI, CHEMICAL COMPOSITION, ORGANIC MATRICES

[+info] VOLUME 1. NUMBER 4. 2003 (1 issue)

A modern regurgitation pellet assemblage created by an unknown avian predator from Olduvai Gorge (Tanzania) was analyzed taphonomically and chemically. The combined use of several analytical techniques allowed us to determine some characteristic effects of bone surface modification induced by the predator´s digestive process. Based on these analyses, it is suggested that the predator is Bubo lacteus, Verreaux´s eagle owl. The chemical analyses of the mineral and organic components of the bones show only small changes in composition and proportion. However, the small alterations favour the hypothesis of post-predation diagenetic changes, which may create bias in the preservation of different types of bones.

Download [Restricted Access]

Taphonomy of Freshwater Turtles: Decay and Disarticulation in Controlled Experiments.

Leonard R. Brand, Michael Hussey, John Taylor.

Keywords: TAPHONOMY, TURTLE, TESTUDINES, DECAY, DISARTICULATION, BIOSTRATINOMY, EXPERIMENTAL TAPHONOMY

[+info] VOLUME 1. NUMBER 4. 2003 (2 issue)

We conducted an experimental study of the timing and nature of taphonomic processes in turtles that allowed a comparison among different environments. We documented decay and disarticulation of freshly-killed aquatic turtles in controlled settings, including freshwater and seawater aquaria, and outdoor terrestrial settings protected from scavengers. The study area was in hot and dry southern California, with scattered winter rains. We transferred some specimens after 53 days from the terrestrial environment to one of two other environments - freshwater, or an outdoor terrestrial cage - simulating increased rainfall. In water, turtle flesh decayed by bacterial action in three and a half to five months, but insect larvae removed the flesh from terrestrial carcasses within two weeks, leaving dry, desiccated carcasses. Turtles disarticulated most rapidly in water, followed by the high rainfall treatment, then dry terrestrial. The sequence of disarticulation of different bones from the body varied considerably, especially in the terrestrial treatment, but there were some consistent trends. Heads and necks, tails, and limbs tended to disarticulate early in the process. Next the carapace, and lastly, the plastron, disarticulated. Minor weathering occurred on the inside surface of some shell bones in the terrestrial environment. These data provide a basis for estimating maximum length of exposure of fossil turtles before burial and for comparison of turtle taphonomy with taphonomy of other small vertebrates.

Download [Restricted Access]

Biostratinomic Patterns in Archosaur Fossils: Influence of Morphological Organization on Dispersal.

Cambra-Moo, O. & Buscalioni, A. D.

Keywords: TAPHONOMY, BIOSTRATINOMY, DISPERSAL STAGES, DISPERSAL SEQUENCES, ARCHOSAURS.

[+info] VOLUME 1. NUMBER 4. 2003 (3 issue)

The dispersal of 122 specimens of fossil archosaurs and lepidosaurians from different localities throughout the world, catalogued as fossil-lagerstätten, has been characterized. The analysis is based on the quantification of dispersal by the evaluation of burial position, anatomical disarticulation, overlap and significant absences of bony elements. Our goal is to identify commonalities of morphological organization, and to reveal dispersal patterns. First, we explore a theoretical space of burial positions, and seek logical alignments of variables in order to understand the sequence of the earliest biostratinomic phenomena. Dinosauria and the basal avian specimens (Archaeopteryx-like organisms) are biased towards lateral burials with crossed forelimbs or hindlimbs. Pterosauria and Ornithuromorpha have ambivalent burial positions, while Enantiornithes and Confuciusornithidae adopt preferentially dorso-ventral burial positions. There is a significantly negative regression coefficient relating overlap and disarticulation-absence. A high percentage overlap corresponds to a high percentage articulation and completeness of body elements, particularly in laterally lying fossils. Conversely, overlap and disarticulation are not significantly related in specimens with a dorso-ventral burial position. Ambivalence in burial positions is associated with singularities in disarticulation patterns. Aves and Pterosauria both diverge from the general disarticulation sequence of diapsids. The results indicate that dispersal has a strong biological component at least in the initial steps of the biostratinomic process.

Download [Restricted Access]

Volumen 10. Number 1. Year 2012.

2019-11-06T22:58:59+02:00October 26th, 2019|Volumen 10. Number 1. Year 2012.|

VOLUME 10. NUMBER 1. 2012

Small Mammal Bone Modifications in Black- Shouldered Kite Elanus caeruleus Pellets from Algeria: Implications for Archaeological Sites.

Karim Souttou, Abdessalam Manaa, Emmanuelle Stoetzel, Makhlouf Sekour, Adel Hamani, Salaheddine Doumandji, Christiane Denys.

Keywords: NEOTAPHONOMY, REGURGITATION PELLETS, NORTH AFRICA, DIURNAL RAPTOR

[+info] VOLUME 10. NUMBERS 1. 2012 (1 issue)

In this taphonomic study we examine bone modifications to small mammal remains in regurgitated pellets from Algerian Black-shouldered Kites, Elanus caeruleus. This is the first paper to examine the diet and taphonomic alterations of this species. It is shown here that the majority of prey remains appearing in the diet of E. caeruleus come from small mammals (93%) and that the modifications on the small mammal bones by this predator are consistent with the "strong" predator modification category (type 4-5 predator) in the schemes proposed by Andrews (1990) and used by Fernando-Jalvo and Andrews (1992). The mean percentage of bone preservation is 28% and the mean percentage of bone fragmentation is 63%. For the most common prey species, Mus spretus, digestion marks occur on 63% of the isolated incisors, 77% of the isolated molars and 90% of femurs with predominantly light to moderate grades of etching. The effects of predation and digestion on different prey species are compared and some differences in preservation are highlighted. The potential role of Black-shouldered Kites as small mammal bone accumulators must not be neglected, particularly in North-African archaeological and palaeontological sites.

Download [Restricted Access]

Flint Patina as an Aspect of “Flaked Stone Taphonomy”: A Case Study from the Loess Terrain of the Netherlands and Belgium.

Philip J. Glauberman, Robert M. Thorson.

Keywords: STONE TOOLS, ARTIFACT TAPHONOMY, FLAKED STONE TAPHONOMY, CHERT, FLINT, PATINA, PALEOLITHIC, THIN SECTIONS

[+info] VOLUME 10. NUMBERS 1. 2012 (2 issue)

This paper describes recent research into variable patinas observed on lithic artifacts from the loessmantled region of Southern Limburg, The Netherlands and Belgian Limburg. There, patina intensity and artifact typology and technology have long been used as indicators of the relative age of surface finds. Though it is true that Neolithic and later flint surface finds never possess the intensity of patina observed on Paleolithic artifacts, this study indicates that sub-aerial exposure likely plays a marginal role in flint patination. Rather, type and degree of patina development appear more closely related to depositional context. We consider data from local surface sites, inferences about the geochemical influence of plant roots, humic acids, soil pH, temperature, and site aspect; and microscopic analysis of thin sections produced from a small sample of artifacts. Finally, we propose a simple model of the flint patination process based on empirical and experimental research on glass hydration. This is a preliminary, conceptual study aimed at developing a working protocol for more extensive flaked stone taphonomy research. Excavations, lithic artifact assemblage analyses, and geochemical studies are currently ongoing, and continue to build on the results of this preliminary research.

Download [Restricted Access]

Much More Than It Was Expected: Preservational Differences of Diaphysis and Epiphyseal Ends of Guanaco (Lama guanicoe) Long Bones in Southern Patagonia (Argentina).

Juan Bautista Belardi, Diego Rindel, Tirso Bourlot.

Keywords: SOUTHERN PATAGONIA, DIAPHYSIS/EPHYFISIS, OPEN-AIR SITES, BONE MINERAL DENSITY, WEATHERING/ABRASION

[+info] VOLUME 10. NUMBERS 1. 2012 (3 issue)

In archeofaunal assemblages from different parts of the world there is a predominance of diaphysis over articular ends. This differential proportion of diaphysis over epiphysis also characterizes a considerable proportion of the faunal samples from Patagonia, especially those from caves and rockshelters. However, the assemblages recovered from open-air contexts in south Patagonia shows an inverse pattern: a predominance of the epiphysis over the diaphysis of guanaco (Lama guanicoe) long bones, contrary to the expectations derived from their respective bone mineral density (BMD) values. The archeofaunal information obtained from six open-air sites is presented and the pattern is evaluated and compared considering the diaphyseal and epiphyseal long bone structure, the densitometric values obtained by Stahl (1999) for South American camelids, the environmental characteristics related with the substrates (lacustrine clay and sand dunes) of the sites and the regional taphonomic information. It is proposed that in dynamic environments such as those here considered, the observed pattern is related to weathering/abrasion, acting differentially on the types and position of the tissues that form the diaphysis and epiphysis. When the diaphysis begins to open and fragment the fracture stops in the epiphysis. Such process would be accelerated in cultural contexts as a result of obtaining nutrients from long bones -considered of low processing cost (sensu Marean & Cleghorn, 2003)- and blanks for artifacts, causes bone to be fractured. Besides, the lack of large carnivores in Patagonia is another important factor that would affect the differential representation on epiphysis over diaphysis. Similar results obtained on different substrates can sustain the expression of the pattern on a regional scale while indicating that it corresponds to openair site contexts in general. Thus, the correlation between present elements and BMD would result in a partial tool to evaluate the integrity of archaeofaunas from Southern Patagonia open-air sites.

Download [Restricted Access]

The Taphonomist´s Corner: Organically preserved fossil soft tissues: a substrate for modern microorganisms.

Maria McNamara

Keywords

Download [Restricted Access]