Irrigated taro (Colocasia esculenta) farming in North Kohala,Hawai‘i: sedimentology and soil nutrient analyses

How did traditional farming transform the natural environment in the Hawaiian Islands? This question is one that has largely been addressed for rainfed farming of crops like sweet potato (Ipomoea batatas), but evidence is lacking for irrigated farming of the critical staple crop taro (Colocasia esculenta). We describe the results of soil nutrient and sedimentological analyses of deeply-stratified pondfield deposits representing a 600-year-long record of irrigated taro farming in the North Kohala District, Hawai‘i Island. Soil is categorized by particle size to determine modes of transport and deposition, and concurrent soil nutrient analyses were conducted to infer shifts in the source of sediments and changes associated with taro harvesting. The advent of farming is clearly detectable in sedimentology, the presence of charcoal found within sediments, and soil chemistry. However, diminished nutrient concentrations can be attributed largely to deposition of a mixture of upstream sediments. Overall, there is no clear evidence for nutrient draw-down by taro harvesting, but we cannot yet rule it out as a factor. This study demonstrates the inherent difficulty of correlating changes in soil nutrients evident in irrigated pondfields with the long term history of soil nutrient cycling.     

Palaeoenvironmental reconstruction of La Olla,a Holocene archaeological site in the Pampean coast (Argentina)

The evolution of littoral palaeoenvironments in the southern Pampas region of Argentina towards the end of the early Holocene and the beginning of the mid Holocene is discussed, and the formation processes of the archaeological site of La Olla are analysed. This site is located in the intertidal zone of the present beach and is remarkably well-preserved. The human occupation at the site has been dated at between 7400 and 6480 yrs BP, and is interpreted as a place for the processing and consumption of the southern fur seal (Arctocephalus australis) and southern sea-lion (Otaria flavescens). It is concluded that biostabilization by microbial mats of the sedimentary structures and archaeological remains that developed and are present on the tidal flat prevented their erosion by wind, turbulence currents and waves. This is what has permitted the exceptional preservation of the site. On the basis of the analyses of one of the sectors of the site it can be concluded that the sedimentary succession of the La Olla site is the result of the coastal environmental changes during the early–mid Holocene in the pre-maximum transgressive episode. During this interval a tidal flat developed on the Pleistocene abrasion platform. Human occupation occurred during the formation of mixohaline marsh, an upper intertidal–lower supratidal zone ecosystem.     

From pedologic indications to archaeological reconstruction: deciphering land use in the Islamic period in the Baida district (north-western Sicily)

The aim of this work was to detect imprints on soil properties from former Islamic land use (9th to 11th century) using a multi-method, soil-chemical approach. Four soil profiles (with buried horizons) found in the vicinities of former Islamic settlements in Sicily were analysed for phosphorus (total, organic and inorganic), nitrogen (total, NO₃⁻ and NH₄⁺), carbon compounds (δ¹³C, lipids, polycyclic aromatic hydrocarbons (PAH) and functional groups), physical and chemical C-fractions and the state of soil weathering. Two soil profiles contained ceramic sherds from the Islamic period. Inorganic nitrogen forms, phosphorous and the PAH content indicated strong impacts from traditional agriculture and/or burning. Radiocarbon dating of soil organic carbon (SOC) fractions from buried horizons showed that distinct changes must have occurred during the Islamic epoch. The isotopic composition of SOC indicated that land use was probably different in earlier times. C₄ plant cultivation was expected but surprisingly lipid analyses did not confirm this. A high amount of aliphates and low C/N ratio indicated a good, long-term SOC stabilisation under the native conditions combined with Islamic land use. The irrigation of the soils probably increased the production of weakly-crystalline Fe forms that helped to stabilise SOC.     

Refuting the technological cornerstone of the Ice-Age Atlantic crossing hypothesis

The “North Atlantic Ice-Edge Corridor” hypothesis proposes that sometime during the Last Glacial Maximum, roughly 26,500–19,000 years ago, human populations from southern France and the Iberian Peninsula made their way across the North Atlantic and colonized North America. A key element of that hypothesis is the apparent similarity between stone-tool-production techniques of Solutrean peoples of Western Europe and Clovis and purportedly pre-Clovis peoples of eastern North America, most especially the supposed intentional use of “controlled overshot flaking,” a technique for thinning a bifacial stone tool during manufacture. Overshot flakes, struck from prepared edges of the tool, travel across the face and remove part of the opposite margin. Experimental and archaeological data demonstrate, however, that the most parsimonious explanation for the production of overshot flakes is that they are accidental products created incidentally and inconsistently as knappers attempt to thin bifaces. Thus, instead of representing historical divergence, overshot flakes in Clovis and Solutrean assemblages mark convergence in the use of the same simple solution for thinning bifaces that produced analogous detritus.     

Paleodiet in northern Chile through the Holocene: extremely heavy δN values in dental calculus suggest a guano-derived signature?

Dental calculus extracted from the teeth of 28 prehistoric human skeletons from coastal and valley archaeological sites in northern Chile that date from the Archaic period (∼2300 BC) to the Late Intermediate period (AD 1476) was analyzed for stable isotope (δ¹⁵N, δ¹³C) compositions. δ¹⁵N compositions were extremely heavy (+17.8 to +33.1‰), but comparable to some studies using conventional human biomaterials (hair, nail, muscle) at other prehistoric sites in northern Chile. There was a negative correlation between δ¹⁵N and δ¹³C for coastal sites, but a positive correlation for valley sites. Results for the valley sites point to a diet that was influenced by marine resources throughout all time periods. The unusually heavy δ¹⁵N values for the coastal sites require a dietary component with a δ¹⁵N composition significantly heavier than that of marine resources. The hyper-aridity at the study area (mean annual rainfall of 0.5–0.6 mm/year) is a likely contributing factor to the production of heavy δ¹⁵N values, but is unlikely to account for the heaviest δ¹⁵N values (>+30‰). One possible explanation for the heaviest δ¹⁵N values is that dietary components were impacted by isotopically-heavy guano, which is abundant in the region. Guano may have been used as a fertilizer during crop cultivation at the onset of the Formative period, continuing through the Historic period after Spanish contact. The indirect impact of guano from abundant bird habitats in the region may have influenced wild foodstuffs harvested throughout the pre-agricultural period. Results provide support for the utility of dental calculus as a proxy for obtaining stable carbon and nitrogen isotope signatures for use in paleodietary studies.     

Mid-Holocene age obtained for nested diamond pattern petroglyph in the Billasurgam Cave complex,Kurnool District,southern India

India has one of the world's largest and most significant bodies of rock paintings and engravings, yet not a single rock art site or image has been directly and accurately dated using radiometric techniques. Here we report on results from the Billasurgam Cave complex near Kurnool in southern India. Although this cave complex has been investigated archaeologically since the late 1800s, it was not until 2008 that a large petroglyph, consisting of the remains of three nested diamond designs on a stalactite, was noted. In order to determine if this petroglyph had been made recently, flowstone was sampled from on top of and below the engraving. Radiocarbon dating revealed a mid-Holocene age of about 5000 cal BP for the petroglyph, but we cannot rule out the possibility that the engraving is several centuries younger. Similar nested diamond designs at some rock painting sites and on a chert core elsewhere in India have been assumed to be Mesolithic. Our result is consistent with this hypothesis, although we note that it also consistent with the creation of the petroglyph in the early Neolithic. We conclude that the Billasurgam engraved diamond design was probably made by Mesolithic foragers of the Kurnool region and is the oldest surviving form of rock art yet directly dated in southern India.     

Nursing mothers and feeding bottles: reconstructing breastfeeding and weaning patterns in Greek Byzantine populations (6th–15th centuries AD) using carbon and nitrogen stable isotope ratios

Traditionally, documentary evidence (mainly medical works and the vitae and miracles of saints) served as the primary source of information for perinatal nutrition in the Byzantine era. In the last decade, however, stable carbon and nitrogen isotope ratio analysis has also been applied for the reconstruction of Byzantine breastfeeding and weaning practices. This paper reviews the documentary evidence for Byzantine weaning and compares it to isotopic data for eight Greek Byzantine skeletal samples from the sites of Eleutherna, Kastella, Messene, Sourtara, Stylos, Nemea, Petras and Servia (6th–15th centuries AD). The documentary evidence suggests that Byzantine children were weaned at a relatively late age. The age patterning of the stable isotope data is not as clear as normally seen at single sites. However, the presence of a higher proportion of elevated values in juveniles aged three years or less suggests that weaning was completed by the fourth year—a pattern consistent with the written sources. The data available from this study allow us to make some tentative suggestions about cultural and temporal differences in weaning, and to recommend directions for further research. A comparison of the Byzantine data presented here to data published for Roman-era sites from the Mediterranean and Western Europe suggests that the Byzantines maintained a Roman-era practice of relatively late weaning. In contrast, medieval data for Western Europe and the few measurements made on post-Byzantine Greek material suggest more variation, with some groups weaning late and others weaning earlier, by two years of age.     

Latest developments in rock art recording: towards an integral documentation of Levantine rock art sites combining 2D and 3D recording techniques

This paper presents a further step in the integral documentation of prehistoric rock art, combining 2D and 3D digital recording techniques. Image processing and digital enhancement techniques are an invaluable aid to obtain high quality and accurate 2D recordings, especially when working with faint motifs or complex superimpositions. But what constitutes a real breakthrough is the possibility of combining 2D digital tracings with metric 3D models, providing a whole set of metric outputs that improve our understanding of the motifs in their context and, at the same time, can be used to deliver accurate metric reproductions.     

Prehistoric land use at an archaeological hot-spot (the rock art park of Campo Lameiro,NW Spain) inferred from charcoal,synanthropic pollen and non-pollen palynomorph proxies

Pollen, non-pollen palynomorphs and charcoal from a colluvial soil surrounded by prehistoric petroglyphs (Campo Lameiro, NW Spain) were studied in order to assess the nature of human activities and their impact on Holocene vegetation patterns. Several phases of anthropogenic impact were observed. (i) Between 7.6 and 6.5 ka cal BP, synanthropic taxa (Urtica dioica type, Plantago lanceolata type) and coprophilous fungi (e.g. Sporormiella-type) are indicative of early (pre-agricultural) creation of small patches of pasture using fire, possibly for incipient animal husbandry or as part of a deliberate strategy to improve game availability. Such activities only had a minor effect on the deciduous Quercus-dominated forest established earlier during the Holocene Thermal Maximum. (ii) Between 5.9 and 4.8 ka cal BP a more intense signal indicative of pastoral activity was detected, corresponding to the Neolithic period. (iii) Between 4.8 and 3.4 ka cal BP, which fits within the hypothetical timeframe of petroglyph creation, the synanthropic and humidity (e.g. Cyperaceae, Mougeotia) indicators diminished while charcoal concentration increased, which can be explained by Mid-Holocene cooling/drying (Neoglaciation) in combination with reduced human impact, or by non-pastoral activities in the area possibly in association with the development of the rock art culture, converting pasture to protected open ground through anthropogenic fires. (iv) During the Late Bronze Age and Early Iron Age (3.4–2.5 ka cal BP), grazing pressure and fire regime intensity are high, coinciding with evidence of regional forest regression, despite an amelioration in climate. (v) Later phases, not corresponding to prehistoric rock art contexts, include a phase of heavy grazing and reduced fire frequency (from ca. 2.5 to 1.2 ka cal BP) as well as the near complete elimination of the deciduous woodland, the expansion of ericaceous shrubland and the evidence of local agriculture and afforestation. These results are consistent with earlier studies in the area and highlight the spatial heterogeneity in the vegetation especially during periods of prehistoric anthropogenic interference.     

A palaeo-opportunistic brachiopod from the Early Permian of Argentina

Neochonetes sp. (Brachiopoda, Chonetoidea) is recorded from the middle to upper part of the early Permian Río del Peñón Formation, Río Blanco Basin, La Rioja, Argentina. It can be recognised as an r-strategist based on distribution, facies, morphological and ontogenic data which agree with the criteria proposed by Levinton and Alexander for recognising palaeo-opportunistic brachiopods. The new record of an opportunistic chonetid suggests that the group may have evolved this adaptative strategy during the late Palaeozoic.