The mean measure of divergence and the use of non-metric data in the estimation of biological distances

The mean measure of divergence as a means of comparing two populations on the basis of non-metric data is described. Some statistical properties of this measure are derived and it is shown that its variance has frequently been misquoted in the literature. Alternative means of comparing two populations are presented and some improvements to the measure of divergence are suggested.     

First record of the ichthyodectiform fish Xiphactinus (Teleostei) from Patagonia,Argentina

Abstract

We report the first record of the genus Xiphactinus from southern South America. The recovered fossil material consists of an associated maxilla and abdominal vertebra, probably derived from latest Maastrichtian marine deposits of the Salamanca Formation in Chubut Province, Argentina. Xiphactinus has been widely reported from Late Cretaceous strata throughout the Northern Hemisphere, although to date, equivalent Southern Hemisphere occurrences include only a single specimen from Venezuela. Our new discovery thus indicates that Xiphactinus had a much more cosmopolitan distribution, encompassing the southern paleolatitudinal extremities of South America during the terminal Cretaceous.

Julieta J. De Pasqua [julietadepasqua@gmail.com], Laboratorio de Anatomía Comparada y Evolución de los Vertebrados, Museo Argentino de Ciencias Naturales ‘Bernardino Rivadavia’, Av. Ángel Gallardo, 470, C1405DJR, Buenos Aires, Argentina;

Federico L. Agnolin [fedeagnolin@yahoo.com.ar], Laboratorio de Anatomía Comparada y Evolución de los Vertebrados, Museo Argentino de Ciencias Naturales ‘Bernardino Rivadavia’, Av. Ángel Gallardo, 470, C1405DJR, Buenos Aires, Argentina. CONICET; Fundación de Historia Natural ‘Félix de Azara’, Departamento de Ciencias Naturales y Antropología, Universidad Maimónides; Hidalgo 775 piso 7, C1405BDB, Buenos Aires, Argentina;

Sergio Bogan [sergiobogan@yahoo.com.ar], Fundación de Historia Natural ‘Félix de Azara’, Departamento de Ciencias Naturales y Antropología, Universidad Maimónides; Hidalgo 775 piso 7, C1405BDB, Buenos Aires, Argentina.     

Measuring the relative topographic position of archaeological sites in the landscape,a case study on the Bronze Age barrows in northwest Belgium

Local topography is an important parameter determining the erection of a certain type of site on a certain location in the landscape. Despite the importance of topography in archaeological landscape research, the role of local topography has remained rather unexplored compared to other specific topographic parameters such as slope, aspect, curvature or visibility. Therefore, three methods to assess the relative topographic position of sites are applied and discussed here. The Bronze Age barrow dataset of northwest Belgium acts as the subject for this methodological case study. First, elevation percentile calculates the area that is lower than the central point within a predetermined neighborhood. Secondly, difference from mean elevation measures the relative topographic position of the central point as the difference between the elevation of this central point and the mean elevation within a predetermined neighborhood. And finally, deviation from mean elevation calculates the relative topographic position of the central point as the difference from mean elevation divided by the standard deviation of elevation, within a predetermined neighborhood. These three methods, each with their advantages and disadvantages, prove to be an added value for archaeological landscape research.     

OSL dating as an alternative tool for age determination of relic charcoal kilns

Chronometric studies of charcoal production remains are largely based on ¹⁴C-dating of associated charcoal. Owing to intrinsic limitations, however, this method provides no meaningful time resolution for post-1650 CE features. We investigate the potential of optically stimulated luminescence (OSL) dating of heated sandy sediments as an alternative and complementary tool for dating charcoal kiln remains. Seven samples from five relic charcoal kilns and 11 complementary samples from the underlying sandy substrate are used. Through a range of procedural tests, we demonstrate that the single-aliquot, regenerative-dose procedure in combination with OSL signals from quartz allows determining equivalent doses both accurately and precisely. For four of the five investigated kilns, OSL ages are consistent with independent age information from ¹⁴C-dating and written sources. Especially for post-1650 CE features, the precision can be significantly better than that of ¹⁴C-dating, and we highlight the potential of OSL dating for distinguishing, relatively, between charcoal production phases with an unprecedented time resolution. We conclude that the approach is a promising alternative to ¹⁴C.     

POST‐COLONIAL RUINS: Archaeologies of political violence and IS

The carefully staged and hyper‐mediated destructions at a number of world‐famous archaeological sites in the area controlled by the Islamic State across Syria and Iraq have often made the headlines in recent months; and these spectacles can be counted among IS' visual markers of identity. In the mainstream media, they have largely been interpreted either as ‘cultural cleansing’ or as an expression of IS' inhumanity, of its barbaric iconoclasm and its criminal fight against idolatry. In this paper, I propose to interpret them as overdetermined acts or rather spectacles of destruction that must be situated within a specific political genealogy. I highlight the long‐standing, deep entanglement between archaeology and (empire and) state building in the Levant.     

Seismic Vulnerability Assessment and Retrofitting Strategies of Italian Masonry Churches of the Alife-Caiazzo Diocese in Caserta

ABSTRACT

Masonry churches represent the major part of the Italian architectural heritage. Recent earthquakes stressed the high vulnerability of these constructions, provoking heavy structural damage and valuable losses. Different approaches have been developed to assess seismic vulnerability of churches. In particular, the complexity related to more detailed models has induced to define simplified methods, which can be used at territorial scale for a preliminary assessment of structural capabilities of homogeneous assets aiming at providing possible post-earthquake damage scenarios and suggesting general interventions strategies. Therefore, the vulnerability assessment of churches is carried out by subdividing the buildings into separate macro-elements, accounting for different possible collapse mechanisms. In this article, a simplified procedure (M.I.T. 2011) has been applied with reference to churches located in Caserta District, particularly those of the Alife-Caiazzo Diocese, by using the MaChro form compilation, previously developed by the authors. The aim of the study is the application of the above procedure in order to verify the possibility to suggest suitable strategies of intervention for structural retrofitting and seismic risk reduction of the churches located in the area under investigation.