The oldest human remains from the Beagle Channel region,Tierra del Fuego

The biohistory of the human peopling of the Fuegian Archipelago and the processes of biocultural adaptation and microdifferentiation of the ethnohistorical ‘canoe’ (‘sea nomad’) and ‘foot’ natives are poorly known. Here we report the oldest human remains of a ‘sea nomad’ native discovered so far in the Beagle Channel region. The specimen consists of a deciduous molar from the site of Imiwaia I, dated to 5870 ± 145 years BP. The microwear pattern indicates the consumption of hard food processed by long chewing cycles. The histomorphometric analysis shows the presence of at least three episodes of stress between 8 and 10.5 months after birth, and an unusually thin neonatal line, suggesting a mechanically non‐stressing birth event. Copyright © 2006 John Wiley & Sons, Ltd.     

Dental trauma and antemortem tooth loss in prehistoric Canary Islanders: prevalence and contributing factors

Differential diagnosis of the aetiology of antemortem tooth loss (AMTL) may yield important insights regarding patterns of behaviour in prehistoric peoples. Variation in the consistency of food due to its toughness and to food preparation methods is a primary factor in AMTL, with dental wear or caries a significant precipitating factor. Nutritional deficiency diseases, dental ablation for aesthetic or ritual reasons, and traumatic injury may also contribute to the frequency of AMTL. Systematic observations of dental pathology were conducted on crania and mandibles at the Museo Arqueologico de Tenerife. Observations of AMTL revealed elevated frequencies and remarkable aspects of tooth crown evulsion. This report documents a 9.0% overall rate of AMTL among the ancient inhabitants of the island of Tenerife in the Canary Archipelago. Sex‐specific tooth count rates of AMTL are 9.8% for males and 8.1% for females, and maxillary AMTL rates (10.2%) are higher than mandibular tooth loss rates (7.8%) Dental trauma makes a small but noticeable contribution to tooth loss among the Guanches, especially among males. In several cases of tooth crown evulsion, the dental root was retained in the alveolus, without periapical infection, and alveolar bone was in the initial stages of sequestering the dental root. In Tenerife, antemortem loss of maxillary anterior teeth is consistent with two potential causal factors: (a) accidental falls while traversing volcanic terrain; and (b) interpersonal combat, including traditional wrestling, stick‐fighting and ritual combat. Steep‐walled valleys (barrancos) and lava fields (malpaís) required agile locomotion and occasional vaulting with the aid of a wooden staff. Accidental falls involving facial injury may have contributed to AMTL. Traditional conflict resolution involved competitive wrestling (lucha canaria), stick‐fighting (juego del palo), and ritualised contests involving manual combat. These activities made a small but recognisable impact on anterior dental trauma and tooth loss. Inter‐personal behaviours of such intensity leave their mark on skeletal and dental remains, thereby providing insight into the lives and cultural traditions of the ancient Guanches. Copyright © 2006 John Wiley & Sons, Ltd.     

Skeletal evidence for hyperparathyroidism in a 19th century child with rickets

The skeletal remains of a child aged 2.5–3.5 years, recovered during archaeological excavations at the churchyard of St Martin's Church, Birmingham, UK, were examined using gross observation, radiography and scanning electron microscopy. Lesions suggestive of the presence of rickets and of secondary hyperparathyroidism were found. This appears to be a first report of secondary hyperparathyroidism in response to rickets in a palaeopathological specimen. The potential of microscopic examination of bone for interpreting disease processes is emphasised. Copyright © 2006 John Wiley & Sons, Ltd.     

Quartz recrystallization and fluid flow during contact metamorphism: a cathodoluminescence study

Cathodoluminescence (CL) images of quartz grains in the Appin Quartzite from the aureole of the Ballachulish Igneous Complex (Scotland) reveal a textural complexity that we interpret in the light of published models of the evolution of the contact aureole. Five distinct generations of quartz can be discriminated in CL. The oldest of these is a dark luminescing mottled quartz (Type 1 quartz) that occurs in the centres of pre‐existing grains, in samples collected from 210 m to 0.1 m from the contact. Dark mottled quartz is interpreted to be unrecrystallized material and has a regional metamorphic CL spectral signature. The onset of contact metamorphism resulted in grain growth visible in CL as a series of fine‐scale alternating bands of bright and dark luminescing material (Type 2 quartz), which we attribute to infiltration of repeated pulses of small amounts of H₂O along grain boundaries. Close to the intrusion, a subgrain‐scale network of intragranular, bright luminescing features could have resulted from either intragranular microcrack‐controlled infiltration of H₂O at high temperatures or intergranular cracking followed by grain growth (Type 3 quartz). Broad bands of bright material on grain boundaries in samples that are inferred to have undergone partial melting are interpreted as quartz crystallized from the melt phase (Type 4 quartz). The final stage in the textural development is marked by a series of aligned fractures, detected in CL by nonluminescing material (Type 5 quartz) and corresponding closely with trails of fluid inclusions. These fractures are interpreted as the pathways for late‐stage, low‐temperature, retrogressive fluids.     

FT-IR measurements of petroleum fluid inclusions: methane, n-alkanes and carbon dioxide quantitative analysis

A recent advancement in petroleum geochemistry is to model fossil oil composition using microthermometric and volumetric data acquired from individual fluid inclusion analysis. Fourier transform infrared (FT‐IR) microspectroscopy can record compositional information related to gas (CH₄ and CO₂) and alkane contents of petroleum inclusions. In this study, a quantitative procedure for FT‐IR microspectrometry has been developed to obtain, from individual fluid inclusions, mol percentage concentrations of methane, alkanes and carbon dioxide as constraints to thermodynamic modelling. A petroleum inclusion in a sample from the Québec City Promontory nappe area was used as standard to record a reference spectrum of methane. The analytical procedure is based on the measurement of CH₄/alkane and CH₄/CO₂ band area ratios. CH₄/alkane infrared band area ratio is obtained after spectral subtraction of the reference methane spectrum. This area ratio, affected by absolute absorption intensities of methane, methyl and methylene, provides a molar CH₄/alkane ratio. Methyl/methylene ratio (CH₂/CH₃) ratio is obtained following procedures established in previous work. CO₂/CH₄ concentration ratio is estimated from relative absolute absorption intensities. Application to natural inclusions from different environments shows good correlation between FT‐IR quantification and PIT (petroleum inclusion thermodynamic) modelling.