Field work updates

This site is dedicated to field work by ACAD members for the benefit of readers.

Sardinia Field Report, August 2009
by Clio Der Sarkissian, PhD Candidate

Above: Excavation at the Longu Fresu cave. Photo courtesy of Clio Der Sarkissian.

The Australian Centre for Ancient DNA was invited to participate in the excavation of four caves in the Mediterranean island of Sardinia in August 2009. These caves are remarkably rich in mortuary artefacts some of which were dated around at 7,000 to 6,000 years ago, making them important relics of the Middle-late Neolithic period. Among these artefacts, human and animal remains, fragments of pottery, mollusk shells, obsidian arrowheads, a stone axe, as well as a very rare example of rock art were discovered. The richness and diversity of these mortuary deposits suggest that spirituality may have been fairly important and complex in Sardinian Neolithic communities.

Clio, from the Australian Centre for Ancient DNA collected human samples on site for further ancient DNA analysis back at the University of Adelaide as part of its participation in the Genographic Project. Sampling human remains directly from the archaeological site provides an exceptional opportunity to maximize the chance of retrieving authentic ancient DNA from valuable samples. DNA undergoes post-mortem degradation that is challenging in itself for palaeogeneticists but is also accompanied by the problem of contamination by modern DNA.  Protective equipment such as gloves, facemasks and full-body suits was therefore worn to collect the samples in conditions reducing the risk of contamination.

Above: Clio Der Sarkissian in the blue suit - mandatory ancient DNA sampling attire! Photo courtesy of Robin Skeates

Sardinians have been described as European genetic outliers and their origin is still veiled in mystery. Ancient DNA recovered from the individuals buried in these Sardinian caves holds the key to better comprehending who these Neolithic farmers were. It could also help investigate the previously hypothesised role of the obsidian trade in the peopling of Sardinia. Moreover, genetic information from Neolithic Sardinian individuals would be very valuable to understand the population dynamics and evolutionary processes that shaped the unique gene pool of Sardinians since the Neolithic. Finally, being the oldest DNA retrieved in Sardinia, ancient DNA from these Neolithic specimens would give a snapshot of the genetic diversity at a time point close to the first settlement of Sardinia and thus shed light on the origins of Sardinians.

Acknowledgements:
The project, directed by Dr. Robin Skeates of the Department of Archaeology, Durham University, UK, is entitled ‘Journeys to the Underworld: Ritual Transformations of Persons, Objects and Caves in Neolithic Central Sardinia’.
Excavations are sponsored by the British Academy, and the Prehistoric Society.

The work is being undertaken (1) with the permission of the Direzione Generale per i Beni Archeologici (Roma), (2) in collaboration with the Soprintendenza per i Beni Archeologici per le Provincie di Sassari e Nuoro, Dott.ssa Giusi Gradoli (COMET – Valorizzazione Risorse Territoriali) Dr. Terrence Meaden (Department of Continuing Education, Oxford University, UK), and (3) with the assistance of the Comune di Seulo.

Teouma Field Report, July 2008
by Christina Adler, PhD Candidate

The Teouma archaeology site is a Lapita cemetery located on the south east coast of Efate, Vanuatu. The Lapita people colonised the pacific between 4 000 and 7000 years ago and are thought to be the ancestors of Polynesians. They are characterised by their notched pottery, domesticated animals and developed navigational skills in combination with their homogenous Austronesian language that was linguistically distinct from the pre-existing Australoid and Papuan populations of Melanesia. The Teouma Lapita site was discovered in 2004 consisting of an extensive cemetery of 50 burials and is still in the progress of uncovering further human remains. Associated with the remains are numerous fragmented, decorated and undecorated Lapita pots. The discovery of the pots and their link to the mortuary practices is a rare finding.
The genetic makeup of the Lapita people is unknown, with debate over a South East Asian origin or greater admixture with Melanesian coastal groups during their migration to Polynesia. A focus of my PhD to elucidate the ancestry of the Polynesian people from ancient DNA of Lapita remains.

This archaeology site provided the means to access freshly excavated skeletal material that improves the chances of extracting authentic ancient DNA, uncontaminated with modern human DNA. I attended the dig sit for two weeks in July to sample human skeletal remains. The sampling was performed in a sterile fashion, using gloves and face masks. Samples were recovered from four individuals located in a small burial pit off the main dig site. These consisted of near complete skeletons in various degrees of disarticulation caused by disturbances from coconut roots. This provides a unique opportunity to analyse DNA from previously uncovered Lapita remains, with the majority of studies to date using museum specimens. In addition it enables us to examine a past human population from which their most recent common ancestor is yet to be determined, aiding in the knowledge of past population migrations in the Pacific area.