INVESTIGATING SEASONALITY AND SEASON OF BIRTH IN PAST HERDS: A REFERENCE SET OF SHEEP ENAMEL STABLE OXYGEN ISOTOPE RATIOS

Intra‐tooth sequential analysis of enamel δ¹⁸O is currently used to investigate birth seasonality in past animal populations, offering new insights into seasonal availability of animal resources, herd management and seasonality of site occupation. Reference data sets are still required to address two major difficulties: (1) that inter‐individual variability in the record of the seasonal cycle is affected by tooth size; and (2) that the season of birth cannot be directly estimated from the timing of tooth growth, because of a delay in enamel mineralization. We present a data set acquired on the lower second molar of 10 modern sheep from Rousay (Orkney) born within a few weeks of each other in April/May and submitted to the same environmental conditions until death. All sheep have recorded a sinusoidal pattern of δ¹⁸O variation spanning approximately a year. From the difference between the expected and the measured time sequence, the delay of enamel mineralization is estimated to be 5–6 months. The data set is then described using a model mainly based on a cosine function. The period, corresponding to the length of the M2 crown formed over a year, averaged 35.8 mm. A very slight variation of tooth growth rate with time and no attenuation of the isotopic signal towards the cervical margin of the crown could be detected in this data set. The lowest δ¹⁸O values, corresponding to the sheep's first winter, were tracked at a distance from the enamel/root junction that varied between 23.0 and 30.3 mm (x_min mean = 27.6 mm); the highest δ¹⁸O values, corresponding to the sheep's second summer, were between 6.3 and 11.6 mm (x_max mean = 9.9 mm). Most of the variability can be attributed to tooth size. When normalized on the period, x_min and x_max are 0.28 (± 0.05) and 0.78 (± 0.05) on average, meaning that the Rousay sheep have recorded the minimum and maximum δ¹⁸O values on average at 78% and 28%, respectively, of the end of the periodic cycle recorded in the second molar.     

REFINING ESTIMATES FOR THE SEASON OF SHELLFISH COLLECTION ON THE PACIFIC NORTHWEST COAST: APPLYING HIGH‐RESOLUTION STABLE OXYGEN ISOTOPE ANALYSIS AND SCLEROCHRONOLOGY

Stable oxygen isotopes from estuarine bivalve carbonate from Saxidomus gigantea were analysed combined with high‐resolution sclerochronology from modern and archaeological shells from British Columbia, Canada, to determine the seasonality of shellfish collection from the archaeological site of Namu. The combination of high‐resolution sclerochronology and a micro‐milled sampling strategy for δ¹⁸O analysis permits a precise estimate of archaeological seasonality, because seasonal freshwater influxes and changes in temperature have dual effects on the δ¹⁸O value of the shell. Sclerochronological analysis identifies the timing and duration of growth that is temporally aligned to stable oxygen isotope results, since δ¹⁸O_shell appears to be strongly influenced by seasonal inputs of very low δ¹⁸O snowmelt‐water from adjacent coastal mountain ranges. The results show that shellfish were collected year‐round at this site over a 4000‐year period, and these data combined with other zooarchaeological lines of evidence support the interpretation of year‐round occupation.     

Seasonal Variation in Fishing Strategies at Two Iroquoian Village Sites Near Lake Simcoe,Ontario

Abstract

In this paper we present an analysis of fish bones from the Barrie and Dunsmore sites, two pre-contact Iroquoian longhouse villages located between Lake Simcoe, and Georgian Bay of Lake Huron, Ontario. We use a combination of fish biology, habitat and spawning data to interpret when and where different fish species were obtained. After identifying co-occurrences of species in major features at each site, we suggest the existence of three fisheries complexes. There is some overlap in species composition between these complexes. In an attempt to distinguish between them, we also investigate probable technique and time of capture through fish bone size distribution. We use our findings to identify inter- and intra-site differences in fish procurement.     

Fishing: Evidence for Seasonality and Processing of Fish for Preservation in the Northern Isles of Scotland During the Iron Age and Norse Times

Abstract

Evidence from fish remains recovered from two sites in the Northern Isles of Scotland is compared to modern data on fish ecology and ethnographic evidence to assess seasonality in terms of resource availability and its implications for economic activities.     

Seasonal Aspects of Bronze and Iron Age Communities at Ra's al-Hadd,Oman

Abstract

Excavations of third millennium BC and later settlement, burial and workshop sites have been carried out at Ra's al-Hadd, Oman in 1988–9 and 1992 under the direction of Dr J. Reade. These excavations form part of the Joint Hadd Project, a multi-disciplinary programme of research co-directed by Dr S Cleuziou, Dr J Reade and Professor M Tosi; the Ra's al-Hadd portion of the Joint Hadd project is sponsored by the British Museum and the Ministry of National Heritage and Culture, Sultanate of Oman and the Ra's al-Junayz portion by I.S.M.E.O and the C.N.R.S.

Environmental evidence from the Ra's al-Hadd sites includes charcoal, charred fruits and seeds, mammal and fish bones, land and marine molluscs. Evaluation of pollen samples is in progress. This paper examines aspects of the ongoing environmental research which aims not only to re-create patterns of resource exploitation through time, but also to chart possible seasonal variability in cultural, subsistence, economic and trading terms. Some comparisons will be made with the dynamics of the present system of seasonal resource exploitation by the Ra's al-Hadd community.     

Analysis of Dental Cementum Rings as an Approach to Azilian Hunting Strategies

Abstract

Perfected by biologists, the analysis of dental cementum rings allows us to know the precise age of the animals studied as well as their season of death. Cementum deposits are layers of various density formed regularly during the animal's life. Large, translucid deposits (observed with polarized light), growing during the good season (spring, summer, autumn), alternate with thin, opaque ones that grow during the bad season (winter). Used to study two French Azilian sites, La Fru and Campalou, this method gives us a better understanding the hunting behaviour of these two human groups. Thus, the Azilian hunters who established their camp in the La Fru and Campalou rockshelters hunted around the site, killing ibex. However, these two groups of predators preferred red deer. Taking advantage of the hunting opportunities offered by the environment, hunters at both sites made opportune captures to the detriment of summer herds of hinds and young. Also, at Campalou, they continued their predation during the rut, concentrating on young animals, probably young males temporarily alone because of the mating season.     

DIGITAL CEMENTUM LUMINANCE ANALYSIS AND THE HAUA FTEAH HOMININS: HOW SEASONALITY AND SEASON OF USE CHANGED THROUGH TIME*

The importance of environmental seasonality and the seasonal cycling of resources to human populations make studies of human responses to seasonality useful to test hypotheses about short‐ and long‐term changes in human behaviour. This paper utilizes digital dental cementum luminance analysis in order to better understand patterns of the seasons of death of Ammotragus lervia at Haua Fteah, Cyrenaica, and to test whether long‐term climatic changes can be detected in dental cement. The overall pattern of the season of death of A. lervia at Haua Fteah is that of year‐round utilization, with a slight increase over time in A. lervia use during the growth period/summer time. The use of digital cementum luminance analysis (DCLA) to detect changes in the seasonal differences between temperatures indicates a trend for increased seasonality in temperature over the past 40 000 years at Haua Fteah. Furthermore, DCLA patterns in the more recent assemblages indicate a shift to a warmer climate from Marine Oxygen Isotope Stage (MIS) 3 to MIS 1.     

Beyond the Barn Beetles: Difficulties in Using Some Coleoptera as Indicators of Stored Fodder

Abstract

The intention of this paper is to provide possible reference points for archaeologists interested in the seasonality of pig meat production and livestock management, by discussing the seasonality of pig production and pig meat preservation in Ireland in the past 250 years. It looks at the role of the pig on Irish farms, concentrating on the native Irish Greyhound pig and Large White Ulster and examines the relationship between crop and livestock management by focusing on the influence of the potato on pig production. As well as discussing the suitability of the potato as a fodder for fattening pigs, it looks at the results of Irish farmers relying on the potato as a food source for both humans and animals, particularly during times of seasonal shortage.

The paper also assesses the influence of climate and technology on the seasonality of pig meat production, outlining methods of slaughtering, curing and storage. Finally, the paper discusses the effects of growing competitive markets on Irish pig production.     

Evidence for Seasonality from Coprolites and Recent Faeces?

Abstract

While in search of proof for seasonality from the pollen analysis of coprolites, a comparative study of fox faeces was initiated. Methodology and detailed results of both the coprolites and fox faeces will be published elsewhere, but some critical remarks are presented here. We realise that factors such as sniffing mixtures of pollen from the soil could obscure the results, so that seasonal indicators are difficult to confirm. Exceptions include the special cases in which butterflies and berries had been eaten. They indicate the flowering period of the insect pollinated plants and the fruiting period respectively. Two additional results of the studies were that a tentative reconstruction of the vegetation turned out to be possible, and the presence of cultivated plants could be demonstrated.     

High Resolution Stratigraphic Distribution of Coprolites within Eneolithic Middens,a Case Study: Hârsova-Tell (Constanta County,Southeast Romania)

Abstract

Quantitative distribution of coprolites, fish bones and mammal bones recovered by wet screening from an Eneolithic midden at Hârsova-tell (southeast Romania) is surveyed within a high resolution stratigraphic framework. The coprolites, all containing bone fragments, are attributed to carnivores/omnivores: dog, pig, man. Highly significant correlation (Spearman's coefficient of rank correlation r_s = 0.46, P < 0.0001) between coprolite distribution and the seasonality-related fish bone distribution suggests that seasonality controls the stratigraphic distribution of coprolites recovered by wet screening within middens. Periods of high fish bone input into the midden, correlated with frequent coprolite occurrences, correspond to the warm season (late spring to early autumn). Assessment of potential factors controlling coprolite distribution within the midden suggests that sections of high coprolite concentration reflect preservation of faeces until embedding in sediments, and/or rapid embedding of faeces. Preservation of faeces is favored by dry periods, characteristic of the summer season in the highly continental climate of the region. Rain, freeze-thaw cycles or other wet season processes favor faeces disintegration. Our results suggest that the stratigraphic distribution of coprolites obtained by wet screening may represent an indicator of seasonality in middens. Additional studies are needed to better characterise this relationship and refine interpretations.