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Developing a tool for using Dental Cementum to explore seasonality of the Early-Middle Epipalaeolithic Azraq Basin, Jordan. . Jennifer Jones: jonesjr11@cardiff.ac.uk Postgraduate Zooarchaeology Forum (PZAF) 14 th November 2009 Cardiff University. Epipalaeolithic in the Azraq Basin.
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Developing a tool for using Dental Cementum to explore seasonality of the Early-Middle Epipalaeolithic Azraq Basin, Jordan. Jennifer Jones: jonesjr11@cardiff.ac.uk Postgraduate Zooarchaeology Forum (PZAF) 14th November 2009 Cardiff University
Epipalaeolithic in the Azraq Basin • Early Epipalaeolithic- 22,000-14,000BP • Middle Epipalaeolithic-14,600-12,500 BP • Natufian- 12,500-10,200BP Key Themes in Epipalaeolthic • Origins of sedentism • Length of occupation • Reason for occupation of sites (Adapted from Garrard et al, 1994:178)
The ‘Mega Sites’ Kharaneh IV • 21,000m² in size • Dates to 20,000-13,000BP • Originally excavated by Muheisen in 1988. • Now being excavated by Maher et al (2008-present). • Kebaran and Geometric Kebaran cultural sequences • Gazelle most commonly consumed animal Kharaneh IV • Wadi Jilat 6 • 18,200 m² in size • Dates to 18,000-12,000 BP • Excavated by Garrard et al (1987), one 2m by 2m trench • Belongs to the Nebekian cultural sequence • Gazelle most commonly consumed animal An example of the level of deflation at the sites.
‘Mega Site Theories’ • Goring Morris(1998)- Sites used for seasonal exploitation of migrating gazelle. • Byrd and Garrard (1990)- Sites represented repeated periods of occupation with possible periods of longer residency. The site of Kharaneh IV, an extensive, site, reminiscent of a tell.
Aims of study • To explore the potential of using dental cementum analysis to investigate season of occupation. • To determine if possible the seasons that each of the ‘Mega Sites’ were occupied. • To try and understand what the season of occupation at the sites means in terms of mobility patterns and territoriality in the Azraq Basin. • To consider the limitations of using cementum analysis and how the technique can be developed for future analysis. • To understand how seasonality studies can be developed in the Azraq Basin. • To consider additional ways of understanding more about territoriality and mobility in the region.
Cementum Analysis • Grows incrementally on a seasonal basis. • increments can show: • Season of Death (from outer band) • Age (based on counting rings) • Possible Causes: • Variations in nutritional content of diet in different seasons • Occlusal stress caused by seasonal dietary variations • Biological causes, hormonal change • Recognised as a successful technique for looking at seasonality • Successfully carried out on gazelle (eg Lieberman 1990, 1991, Stutz and Lieberman, 2007). Dentine Enamel Cementum Mandible
Epipalaeolithic diet of Gazelle • Environment similar to today. • Two mains season • November-March- Main for of diet low quality grass and forbs • April-October- Higher quality browse consumed • Studies of modern gazelle (Lieberman, 1993) suggest: • Wet season growth (Nov-March) approx 2.5µm per month • Dry season growth (April-Oct) approx 4.6 µm per month
Selecting the Sample • Gazelle most common on Levantine Epipalaeolithic sites. • M1 used-largest accumulation of cementum. • Tooth needed to be in situ in the mandible-protects outer band of cement • Kharaneh IV Mandibles • Taken from 2008 and 2009 excavations. • Area A (Middle Epipalaeolithic) and Area B (Early Epipalaeolithic) sampled. • Taken from a range of different contexts. • Total number successfully processed: 12 • Wadi Jilat 6 Mandibles • Taken from 1984 excavations of a 2m X2m trench. • Mandibles all from upper levels, making them contemporary with the Kharaneh sample. • Taken from a range of different contexts. • Total number successfully processed: 5
Methodology • Fully record teeth in mandible including: • Toothwear according to Payne (1973) and Munro et al (2009). • Measurements (Von den Driesch, 1976) • Photographic record of all sides • Teeth extracted using Dremel Diamond edged circular saw. • Soaked in Resin for 2 weeks • Resin set in water bath in fridge overnight • Blocks of resin sectioned using a Beuhlerisomat diamond tipped circular saw. • Polished on 3 µm and 1 µm- ‘mirror polish’ achieved • Light microscopy- at 40X magnification • Photomicrographs taken using a Nikkon E995 microcam.
Examples of the Cementum Photomicrographs Dentine-Cement Junction Dentine-Cement Junction thin translucent band. Opaque band Translucent band Opaque outermost band Opaque band Outermost thin translucent band. Dentine Void A photomicrograph of the dentine-cement junction of the distal root of Specimen 2 dentine-cement junction of the outer edge of the distal root edge of Specimen 4
Discussion • Multiple seasons of occupation at both sites. • Likely that the sites were being occupied for prolonged periods of time. • Possible aggregation of populations during times of hardship. • ‘mega sites’ way of staking claim over a specific area.
Further avenues of Research • Kharaneh IV- potential for study of new mandibles excavated over next few years. • Wadi Jilat 6- available sample exhausted, need to look at other seasonality indicators: • Age profiles of gazelle. • Presence of migratory birds. • Archaeobotanical remains • Understanding site function: • Skeletal representation • Butchery marks • Non zooarchaeological investigations • Tools types represented and their function • Other material culture eg shell beads
Evaluation of Pilot Study • Sample size small (but comparable to other cementum studies). • Temporal resolution an issue. • Freshly excavated samples worked better. • Thin sections and higher magnifications may enable more detailed resolution of seasonality. • Not possible to tell effects of chemical digenesis on the samples. • Need to use several different lines of evidence. Specimen 24, Wadi Jilat 6. The resin did not impregnate the tooth well, leaving air gaps, and causing the cement to pull away from the root, meaning that cement banding was obscured.
Conclusions • Cementum Analysis can be applied to the ‘mega sites’. • Patterns suggest sites were occupied for extended periods of time, rather than repeatedly at a specific time of year • Larger samples required in future. • More detailed analysis may enable greater seasonal resolution. • Important to use a range of seasonality indicators. • Need to consider other aspects of zooarchaeology and material culture, to understand more about site function, and relationship between sites.
Acknowledgements Many thanks to: • Louise Martin (UCL) • Sandra Bond (UCL) • Lisa Maher and Tobias Richter (Cambridge/UCL) ...and all members of the Epipalaeolithic Foragers in Azraq Project (EFAP).