Wednesday, 27 January 2016

From tiny seeds grow.......by PhD student Leslie Bode

Me looking rather seed-crazed in the
Archaeobotany lab at Bar Ilan University 
Hi, my name is Leslie Bode, and I am exploring new applications of archaeobotanical isotopic research. I am currently a 3rd year PhD candidate at the University of Nottingham and am co-supervised between Archaeology (Dr Alexandra Livarda) and Geography (Dr Matthew Jones). I also receive a lot of extra isotope guidance from Dr Angela Lamb at the British Geological Survey.

Thanks to a NERC Isotope Geosciences Facility grant, I am using a combination of archaeobotanical and stable carbon isotope (δ13C) analysis of charred (carbonized) seed remains from Kharaneh IV (a ca. 20,000 year old archaeological site in the Azraq Basin in Eastern Jordan) to test whether the plants living during this period and, by extension, the hunter-gatherers using this ancient site experienced water stress. I’m especially interested in whether water stress increased leading up to the site’s abandonment almost 20,000 years ago: did a lack of water contribute to collapse?

One of the well organized boxes of
reference material at Bar Ilan University 
Identifying the ancient, charred seeds from Kharaneh IV to the species level is a real challenge due to the small number of seeds, how well preserved they are, and their small size (one seed would, literally, fit on the head of a pin). Adding to this, botanical reference collections are few and far between for this time period and region.  To help identify these mystery seeds, I have been traveling to reference collections around the UK, such as the ‘Hillman’ Near Eastern seed collection in the Department of Archaeology at the University College London, and the University of Sheffield’s Archeobotanical reference collection.  Along the way, I have been graciously helped by experts in this area (notably: Sue Colledge at UCL and Mark Nesbitt at Kew Gardens).  Despite these productive, knowledge building research visits, I was still left with a lot of unidentified material and needed to get closer to the source of these seeds.

So, in November 2015, I travelled to the archaeobotany labs at Bar Ilan University in Israel to have a look at their impressive collection of Levantine and Near Eastern seeds.   While visiting, I was fortunate to meet Prof. Ehud Weiss and Dr Yoel Melamed and the friendly and amazing team of archaeobotanists who work in their labs, who have excellent knowledge of the local and regional flora on top of an archaeobotanical perspective on the early time period I am interested in. I was blown away by the extent of the reference collection at Bar Ilan.  Every species and even various varieties I had hoped to see were there, waiting for me in well organised boxes of slides and capsules. I only managed a few days of browsing the reference collection, but plan to return during the final stages of identification for the material I am studying from Kharaneh IV.
Map of the location of Khareneh IV in Eastern Jordan

In the meantime, I’ve been back in the lab at BGS, working with Dr Angela Lamb to measure δ13C in my seeds and learning a lot about statistical analyses and some of the real challenges to using isotopic methods on such ancient seeds. The initial results have certainly given me lots to think about, but I won’t give any of them away here. Keep an eye out for the publication that will hopefully result from our findings.







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