First record of a fossil selenariid bryozoan in South America

López-Gappa, J., Pérez, L.M. & Griffin, M. February 2017. First record of a fossil selenariid bryozoan in South America. Alcheringa XX, xxx-xxx. ISSN 0311-5518.

Selenariidae Busk 1854 (Bryozoa) is considered endemic to Australia and New Zealand. Here we describe a new species of Selenaria Busk 1854 from the lower Miocene Monte León Formation (Patagonia, Argentina). Selenaria lyrulata sp. nov. is characterized by autozooids with a lyrula-like, anvil-shaped cryptocystal denticle, opesiular indentations and lateral condyles, as well as avicularia with a shield of fused costae. This is the first record of a selenariid bryozoan in South America.

Juan López-Gappa [lgappa@macn.gov.ar] CONICET—Museo Argentino de Ciencias Naturales. Av. Ángel Gallardo 470, C1405DJR, Ciudad Autónoma de Buenos Aires, Argentina; Leandro Martín Pérez [pilosaperez@gmail.com] and Miguel Griffin [patagonianoyster@gmail.com], CONICET—División Paleozoología Invertebrados, Museo de La Plata. Paseo del Bosque s/n, B1900FWA, La Plata, Argentina.     

Ancient social landscapes of northwestern Argentina: preliminary results of an integrated approach to obsidian and ceramic provenance

This article presents the results of ongoing instrumental neutron activation analyses (INAA) conducted on archaeological artifacts from the Formative period of northwestern Argentina (NWA). These studies are part of a wider archaeological project that seeks to understand the structure of the social landscape of the period by examining domestic and burial evidence from a wide range of villages across the area known as the southern Calchaquí valleys. Elemental data is discussed in the light of its potential contribution to reassess past social interaction strategies in the region.     

Reflections on North American Pacific Coast prehistory

The Pacific Coast of North America was occupied by many distinctive groups of coastal hunter-gatherers at the times of early contacts with Europeans. Despite significant cultural diversity, Pacific Coast peoples shared lifeways oriented toward generally similar marine, nearshore, littoral, and estuarine habitats. In this paper, we examine some major issues that guide much of the archaeology done along the Pacific Coast, then discuss some of the theoretical and methodological problems that limit the efficacy of archaeological reconstructions. Most archaeological research conducted on North America's Pacific Coast has been oriented toward the search for the origins and development of a variety of cultural patterns. A comparative review of California and Northwest Coast sequences provides interesting parallels and discrepancies in the approaches taken in studying some of the major issues in Pacific Coast prehistory.     

Human corpse manipulation and the body as symbol: A case study from the Eastern Pampa–Patagonia transition (Argentina) during the Final Late Holocene

Human body manipulation and secondary burials are widespread funerary practices in many areas of the world. The archaeology of the Pampas and North-Eastern Patagonia, Argentina, is no exception. In this paper, archaeological case studies from the lower basin of the Colorado River during the Final Late Holocene (ca. 1000–250 years BP) are presented and discussed. Secondary burials were recovered that indicated an intentional manipulation of bodies. Evidences of cut marks and the coloring of bone surfaces were recorded. The bundles were composed of individuals of both sexes and diverse age categories. The Pampean region and North-Eastern Patagonia witnessed significant hunter–gatherer population dynamics during the last 1000 years BP. Climatic, ecologic, demographic, and economic explanations have been proposed as the background to these changes. In this paper, it is argued that accompanying these factors, as part of a broader socio-cultural scenario, were significant social interaction networks and processes of social complementarity between groups. In this context, it is proposed that the complexity observed in relation to the handling of bodies is part of a worldview in which the body was seen as material culture – as a symbol – that played an important role for the community in group identity maintenance in a cultural context undergoing significant organizational changes.     

Geographic variation in bone carbonate and water δO values in Mendoza,Argentina and their relationship to prehistoric economy and settlement

Questions of mobility, settlement pattern, and their relation to economic organization and resource use are central to ongoing work in central-western Argentina. Here we analyze geographic patterns in the distribution of 178 human bone carbonate δ¹⁸O samples, 46 human tooth enamel carbonate δ¹⁸O samples, and 48 water δ¹⁸O samples from throughout the Andean Cordillera and Monte Desert and evaluate their implications for prehistoric mobility and economy. We confirm and refine previous generalizations regarding a highland/lowland dichotomy in water δ¹⁸O values and show that the range of human carbonate δ¹⁸O values generally reflect available water sources. While there is little within-lifetime change in patterns of water use, we show that most individuals have stable isotope signatures consistent with water use from multiple areas or areas other than where they were ultimately interred. These data indicate high levels of residential mobility, and we conclude by discussing their implications for our understanding of regional prehistory.     

论张学良与“西北国防政府”计划

张学良自成局面的设想和中共先行建立地区性国防政府的策略 ,是促成“西北国防政府”计划产生之两大要素。但在该计划的实施步骤及是否反蒋、如何打通苏联等问题上 ,张与中共间存在着某些潜在分歧 ,加之中共的政策由反蒋抗日急剧转向逼蒋抗日 ,打通苏联亦未能成功 ,从而导致该计划终归流产     

Sapwood estimates in the interpretation of tree-ring dates

Many timber finds lack some or all of the outer, sapwood rings formed in the years just before felling. In order to estimate felling date once the outermost remaining ring has been dated, it is necessary to estimate the number of sapwood rings originally present. Methods doing this for oak are reviewed in the light of an intensive study of living trees at one site and an extensive study of 175 samples from living trees in North Wales and northwest England. Some methods reported in the literature are found to be invalid. A method reported by Hollstein (1965) is most reliable, with modifications for known variations in sapwood number with position in the tree. At present the best available estimate is that a value of 30 sapwood rings be used (95% confidence limits: 19–50).     

Assessing Conflict and Exchange: The Defensive and Access Layout of La Alumbrera (c. AD 1000–1480, North-west Argentina)

Abstract

The Regional Development Period (c. ad 1000–1480) in north-west Argentina is characterized, among other important features, by the coexistence of two phenomena seemingly opposed: a constant situation of violent conflict between communities and the maintenance or even intensification of interregional goods exchange networks. Although recent studies recognize the simultaneity of these processes, only a few scholars asked how communities dealt with the necessity of protecting themselves as well as obtaining distant resources. In this paper we present the analysis of the defensive and access layout of La Alumbrera archeological site which has the peculiarity of condensing features that may illustrate an example of how conflict and exchange coexisted at a local scale.     

First record of fossil woods from the Mariño Formation (Miocene), Mendoza,Argentina and their palaeobiogeographical implications

The first Miocene records of silicified fossil woods from the Mariño Formation, Potrerillos area, Andes Precordillera, Mendoza province, Argentina are described. Rhaphithamnoxylon artabeae gen. et sp. nov. is described as the first fossil wood referable to Verbenaceae from Argentina. This new fossil species is related to extant Rhaphithamnus Miers, sharing the following anatomical features: diffuse porosity, distinct growth ring boundaries, numerous small to very small vessels, commonly in radial multiples, 1–3 seriate rays, and heterocellular and scarce paratracheal axial parenchyma. Rhaphithamnus contains only two extant species: R. spinosus (A.L. Juss.) Moldenke, which occurs in the Valdivian forests of Chile and Argentina, and R. venustus (Philippi) Robinson, which is endemic to the Juan Fernández Islands. Representatives of Verbenaceae are distributed predominantly in the Americas from Patagonia (Argentina) to Canada, and they are inferred to have originated in South America. The fossil wood described herein provides new age and geographical constraints on the raphithanoid lineage within Verbenaceae. Other fossil woods recorded from the Mariño level are retained under open nomenclature, as they possess a combination of mostly solitary broad vessels, and smaller vessels in radial multiples or in clusters, with numerous, vasicentric to confluent axial parenchyma, and heterocellular, high rays. Thus, they have features akin to dicotyledonous lianas or vine-like or small shrub species.