Towards a three-dimensional cost-effective registration of the archaeological heritage

Archaeological practice within the European context of heritage management is facing huge challenges in ways of recording and reproduction of ex-situ preserved sites. As a consequence of the Valletta-treaty, numbers of archived images and drawings of excavated structures as prime sources of past human activity, are exponentially growing. Contrarily to portable remains however, their future study and revision is biased by the two-dimensional character of the recorded data, rendering difficult their future reconstruction for new study or public dissemination. A more realistic three-dimensional (3D) way of recording and archiving should be pursued. In this paper the possibilities for 3D registration of archaeological features are examined in a computer vision-based approach using the PhotoScan software package (Agisoft LCC). It proved to be a scientific and cost-effective improvement compared to traditional documentation methods. Advantages can be found in the high accuracy and straightforwardness of the methodology. The extraction of an orthophoto or a Digital Terrain Model from the 3D model makes it feasible to integrate detailed and accurate information into the digital archaeological excavation plan. The visual character of 3D surface modeling offers enhanced output-possibilities allowing a better documentation of in-situ structures for future research and a higher public participation and awareness for the archaeological heritage.     

Ancient DNA evidence for genetic continuity in arctic dogs

The domestic dog fulfills many functions for their human companions, such as hauling, guarding, and protection. Consequently, humans have taken dogs to nearly every corner of the globe. Recent translocations of Western dogs stemming from the Victorian era dog fancy have erased some of the ancient genetic signatures of these earlier migrations. Here we used DNA of ancient and modern dogs from the North American Arctic of Alaska and Greenland to assess their genetic continuity in time and space. We successfully sequenced 23 archaeological (ca. AD 1250–1910) and recent (ca. AD 1930–1990) surface-collected Canis bone and tooth samples and compared them to 51 modern Inuit Sled Dogs and to published sequences of modern Alaskan Malamutes (and additional Inuit Sled Dogs) to test for evidence of lineage replacement or genetic continuity through time. Ancient samples from Alaska and Greenland and modern sequences from Greenland all contained a high frequency of haplotype A31, which was previously described only in modern North American Arctic dogs. Thus, A31 was a common thread tying the entire North American Arctic together prior to European colonization and, in the Eastern Arctic, indicates genetic continuity between past and present dogs as well. However, A31 is rare in modern Alaskan dogs, consistent with post-colonization replacement by Eurasian matrilines.     

Determining the provenance of black limestone artifacts using petrography,isotopes and EPR techniques: the case of the monument of Bocco

This paper investigates the provenance of the black limestone of the monument known as Bocco, named after the king of Mauretania who presented Silla with this work as a sign of his submission to the power of Rome. A multi-method approach, comprising petrographic observations, carbon and oxygen isotope composition and electron paramagnetic resonance (EPR) spectra characteristics, was used for this purpose. The monument is part of a reconstruction of a rectangular base (approx. 8 × 2 m) which is likely to have served as the base for a bronze statuary group and is currently composed of six blocks of limestone whose exterior is engraved with a fine frieze. The results of the different analyses were compared with the data of a published database of the most important black limestone quarries exploited during Roman times in the Mediterranean area. The petrographic and physico-chemical parameters did not prove to be very effective in determining the provenance of the black limestone of Bocco; the isotopes result even raised some uncertainty as to whether all six blocks came from the same quarry, though this doubt was dispelled by the EPR data and, above all, by the evident petrographic similarity between them. Differences in the isotopic composition of the various blocks may be due to an in situ rock alteration process caused by interaction with an aqueous fluid. It was, however, impossible to determine with certainty the origin of the material of the stone artifact using the database available; it is possible that the black limestone of Bocco came from an ancient quarry that is likely to be located in north western Africa but has not yet been uncovered. An alternative hypothesis, according to which the limestone used for the monument of Bocco came from the ancient quarry of Ain el Ksir, one of the Tunisian quarries present in the database, is also discussed.