Actualistic research into dynamic impact and its implications for understanding differential bone fragmentation and survivorship

The relationship between bone mineral density and archaeological bone survivorship has played a critical role in zooarchaeological and taphonomic studies in recent decades. Numerous studies have suggested that higher-density skeletal element portions survive more frequently than lower-density element portions when archaeological assemblages are affected by some taphonomic processes. Interpretations of density mediated destruction have become commonplace in the archaeological literature, and are often used to explain the absence of certain bone elements and element parts in zooarchaeological assemblages. This study explores the effects of rockfall on bovid elements in varied environmental conditions and the differential survivorship of their element parts, and has implications for understanding the taphonomic processes through which bones are subjected to dynamic loading. Actualistic rockfall experiments conducted on twelve samples of frozen, fresh, and semi-dried bovid bones reveal that the generally low-density epiphyseal ends of bone elements resist fracture and analytical deletion with more frequency than the higher-density diaphyses. This evidence suggests that bone density does not correlate with likelihood of breakage or effective archaeological “destruction” when rockfall and other processes that result in dynamic impact are in action. While this research does not question the relationship between bone mineral density and the likelihood for archaeological survivorship as the result of some taphonomic processes, it presents one specific set of taphonomic processes that result in the differential survivorship of low density bone elements parts and the fragmentation and destruction of higher density element parts. This research presents evidence that shows that dynamic impact is a process capable of fragmenting and sometimes destroying high-density elements while low-density elements survive.     

A biface and blade core efficiency experiment: implications for Early Paleoindian technological organization

Early Paleoindians often are described as highly mobile hunter–gatherers who employed lithic technologies designed to minimize stone transport costs. We experimentally reduced blade and bifacial cores and found both reduction strategies to be equally efficient for the production of useable flake blanks. Further, when compared to similar core reduction experiments, the results of this study showed no significant differences in core efficiency between bifacial, prismatic blade, and wedge-shaped blade core reduction. Biface and blade cores with initial weights greater than 1000 g produced useable flakes as efficiently as informal cores. However, bifacial and blade core efficiency decreased with initial core weight. When considered in terms of Early Paleoindian technological organization, differences in core efficiencies suggest that Folsom groups employed core reduction strategies designed to minimize stone transport costs, but Clovis groups did not.     

Investigating interrelationships between Lower Palaeolithic stone tool effectiveness and tool user biometric variation: implications for technological and evolutionary changes

Lower Palaeolithic hominins are thought to have been dependent upon stone tools during the acquisition and processing of food resources. Hence, it is hypothesized that the evolutionary advantages provided by efficient stone tool use may have selected for anatomical changes observed in the hand during this period. Similarly, hominin manipulative capabilities are suggested to have been of consequence to Lower Palaeolithic technological choices and tool use capabilities. The extent and character of these relationships are not, however, fully understood and it is not known whether these hypothesized co-evolutionary and co-dependent relationships are consistent across varying technological and task-type conditions. Here, six key biometric parameters of the hand are investigated in terms of their statistical relationship with cutting efficiency using both flakes and handaxes over extended periods of use and in multiple types of cutting task. Results indicate that (1) both handaxe and flake cutting efficiencies are significantly related with biometric variation of individual tool users, (2) relationships between biometric parameters and efficiency are consistent across extended durations but vary dependent upon task-type conditions, (3) manipulative strength is the most significant biometric trait in terms of predicting flake efficiency, while (4) hand size is the strongest predictor of handaxe cutting efficiency. These results demonstrate the long-term impact that stone tool use likely had on the evolution of hominin biometric variation during the Lower Palaeolithic, while also highlighting the variable influence of different tool use contexts. Most notably, results indicate that the onset of the Acheulean may have been dependent, a priori, upon hand dimensions that are close to the modern human range, and that prior to the appearance of this anatomy, handaxe use would have been an impractical (i.e. inefficient) tool use behaviour compared to the use of flakes.     

Stone-boiling maize with limestone: experimental results and implications for nutrition among SE Utah preceramic groups

Groups living on Cedar Mesa, SE Utah in the late Basketmaker II period (Grand Gulch phase, AD 200–400) were heavily maize-dependent, but lacked beans as a supplemental plant protein, and pottery vessels for cooking. Common occurrence of limestone fragments in their household middens suggests 1) limestone may have been used as the heating element for stone-boiling maize and 2) this practice might have made some maize proteins more available for human nutrition. Experiments examined these possibilities; results indicate that stone-boiling with Cedar Mesa limestone creates an alkaline cooking environment suitable for nixtamalization of maize kernels, and that maize cooked in this fashion shows significant increases in availability of lysine, tryptophan, and methionine. Archaeological limestone fragments from a Grand Gulch phase site show amounts of fragmentation and changes in density consistent with repeated heating. While not conclusive, these data indicate that further research (e.g., examination of archaeological limestone fragments for maize starch grains or phytoliths) is warranted. It is suggested that greater attention be paid to archaeological indications of stone-boiling with limestone among maize-dependent but pre-pottery societies.     

A theoretical framework for evolutionary economic geography: industrial dynamics and urban growth as a branching process

We propose a framework that specifies the process of economicdevelopment as an evolutionary branching process of productinnovations. Each product innovation provides a growth opportunityfor an existing firm or a new firm, and for an existing cityor a new city. One can then obtain both firm size and city sizedistributions as two aggregates resulting from a single evolutionaryprocess. Gains from variety at the firm level (economies ofscope) and the urban level (Jacobs externalities) provide thecentral feedback mechanism in economic development generatingstrong path dependencies in the spatial concentration of industriesand the specialization of cities. Gains from size are also expected,yet these are ultimately bounded by increasing wages. The contributionof our framework lies in providing a micro-foundation of economicgeography in terms of the interplay between industrial dynamicsand urban growth. The framework is sufficiently general to investigatesystematically a number of stylized facts in economic geography,while at the same time it is sufficiently flexible to be extendedsuch as to become applicable in more specific micro-contexts.A number of extensions related to the concepts of knowledgespillover and lock-in, are also discussed.     

Investigating compositional diversity among Fijian ceramics with laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS): implications for interaction studies on geologically similar islands

This paper presents a ceramic provenance analysis of 260 Fijian sherd clays by laser-ablation inductively-coupled-plasma mass spectrometry (LA-ICP-MS). Our analyses define three compositional groups in western Fijian ceramics distributed across the 2700 year ceramic sequence. Frequencies of compositional groups represented in the diachronic assemblages indicate an increasing spatial sphere of interaction until approximately 1500 BP. By 1000 BP interaction had spatially contracted to a significant degree. These findings suggest re-evaluation of current ideas about interaction in the southwest Pacific is necessary.     

Charcoal reflectance measurements: implications for structural characterization and assessment of diagenetic alteration

Charcoal is a valuable source of archaeological and palaeoenvironmental proxy data. However growing evidence suggests that production conditions can strongly influence post-depositional alteration of charcoal. Consequently, both reconstruction of production temperature and understanding of the potential for diagenetic alteration are of great interest. Here, we use mean random reflectance (Ro_mean) in conjunction with other chemical characterization methods to address these questions. Ro_mean was obtained for a suite of modern analogue charcoal, produced under controlled conditions, and for a series of natural charcoal samples, obtained from archaeological and palaeoenvironmental deposits. Ro_mean proves to be a robust measure to assess formation temperature for samples produced at 400 °C and above, even after exposure to highly oxidizing conditions. Ro_mean is also useful for samples formed between 300 °C and 400 °C. However, if an assemblage of charcoals has been exposed to oxidizing conditions, lower temperature charcoals may be preferentially lost. It is apparent that charcoal produced at lower temperatures is more highly susceptible to chemical oxidation, and that there is a continuum in charcoal degradation potential, dependant upon fuel material and production conditions.     

Dating North Asian surface assemblages with ostrich eggshell: implications for palaeoecology and extirpation

East Asian ostrich (Struthio anderssoni Lowe) was thought to have become extinct sometime in the Late Pleistocene. Petroglyphs portray ostrich with Pleistocene animals, and ostrich eggshell (OES) fragments and ornaments from Holocene sites were considered to be older fossils. Here we summarize previous radiometric dates for ostrich eggshell (OES) and present 15 new calibrated accelerator mass spectrometry (AMS) dates, indicating that ostrich survived in Mongolia and northern China until at least 8.9 ka BP. The dates in our sample population suggest a correlation between Struthio and warm steppe environments, with extirpation probably related to essential changes in Holocene steppe ecosystems including human expansion. This study assesses the usefulness of Asian OES for archaeological dating by AMS, constrains the date of Asian ostrich extirpation, and investigates palaeoenvironmental implications of ostrich survival and extinction.     

Morphological comparisons of metacarpal I for Australovenator wintonensis and Rapator ornitholestoides: implications for their taxonomic relationships

WHITE, M.A., FALKINGHAM, P.L., COOK, A.G., HOCKNULL, S.A. & ELLIOTT, D.A., 2013. Morphological comparisons of metacarpal I for Australovenator wintonensis and Rapator ornitholestoides: implications for their taxonomic relationships. Alcheringa 37, 1 - 7. ISSN 0311-5518.

Various comparisons of left metacarpal I of the Australovenator wintonensis holotype have been made with Rapator ornitholestoides. These specimens were identified as being morphologically more similar than either was to that of the neovenatorid Megaraptor namunhuaiquii. Owing to the poor preservation of A. wintonensis and R. ornitholestoides, distinct morphological separation between the two appeared minimal. The recent discovery of a near perfectly preserved right metacarpal I of A. wintonensis enables a direct and accurate comparison with R. ornitholestoides. Distinct morphological differences exist between the metacarpals of the two species. A re-evaluation of the age of the A. wintonensis holotype site (AODL 85 ‘Matilda Site’) with zircon dating reveals a maximum age of 95 Ma, 10 Ma younger than the Griman Creek Formation at Lightning Ridge, from which R. ornitholestoides was recovered. This age difference detracts from the probability that the specimens belong to the same genus.

Matt A. White? [fossilised@hotmail.com], School of Engineering, The University of Newcastle, Callaghan, New South Wales 2308, Australia; Peter L. Falkingham? [pfalkingham@rvc.ac.uk], Department of Comparative Biomedical Sciences, Structure and Motion Laboratory, Royal Veterinary College, London, UK; Alex G. Cook [alex.cook@y7mail.com] and Scott A. Hocknull [scott.hocknull@qm.qld.gov.au], Ancient environments, Queensland Museum, Hendra, Queensland, 4011, Australia; David A. Elliott [david.elliott@aaod.com.au], Australian Age of Dinosaurs Museum of Natural History, The Jump Up, Winton, Queensland, 4735, Australia. ?Also affiliated with Australian Age of Dinosaurs Museum of Natural History, The Jump Up, Winton, Queensland 4735, Australia. ?Also affiliated with Department of Ecology and Evolutionary Biology, Division of Biology and Medicine, Brown University, USA. Received 22.9.2012; revised 13.1.2013; accepted 17.1.2013.     

Tongan and Samoan volcanic glass: pXRF analysis and implications for constructs of ancestral Polynesian society

A provenance study of volcanic glass specimens from 12 archaeological sites in the Kingdom of Tonga is carried out employing pXRF (portable X-ray fluorescence) analysis. To accomplish this, volcanic glass samples from previously identified sources in northern Tonga and the adjacent islands of Samoa are analyzed. Results indicate inter-island voyaging and interaction over a 600 km linear distance along the Tongan island chain from first Lapita settlement ca 2900 BP throughout later prehistory. Tongan volcanic glass, however, is not found in Samoa and, with the exception of one late prehistoric specimen, Samoan volcanic glass is not present in Tonga. This distribution challenges current concepts of an integrated ancestral society and homeland common to Tonga and Samoa from the Lapita period onward.     

'Proactive fast-tracking' diffusion of supermarkets in developing countries: implications for market institutions and trade

Supermarkets have spread extremely rapidly in developing countriesafter the ‘take-off’ in the early to mid-1990s.Former analyses of supermarket diffusion have not adequatelyexplained the sudden burst and then exponential diffusion ofsupermarkets in the late 1990s and early 2000s. We argue thatrather than taking demand and market institutional and organizationalconditions as ‘exogenous’, as former analyses havetended to do, modern food retailers instead have treated localconditions as substantially ‘endogenous’. To enabletheir rapid growth, supermarkets undertake ‘proactivefast-tracking strategies’ to alter the ‘enablingconditions’ of entry and growth. Beside the retail investmentsthat have been extensively treated in recent literature, theseproactive strategies focus on improving the ‘enablingconditions’ via (i) procurement system modernization and(ii) local supply chain development. One important strategyretailers have used to facilitate (i) and (ii) is to form symbioticrelationships with modern wholesale, logistics and processingfirms. An example we address is ‘follow sourcing’,where a transnational retailer encourages transnational logisticsand wholesale firms with whom the retailer is working in homemarkets, to locate to the developing country. This is a spurto globalization of services in support of retail. Follow-sourcinghas been treated for example in the automobile manufacturessector (follow-sourcing from spare parts manufacturers)—butnot in the food sector. A second important strategy is thatof multi-network-sourcing, in which supermarkets source fromnational, regional and global networks. We analyze that strategyhere, adding to the literature which to date has touched onthis theme only scantly, and for the first time identify typicalpaths, present preliminary evidence (from Central America andIndonesia) concerning this multi-sourcing-network strategy anddiscuss trade implications. One of these is the move to primacyof South–South trade in supermarket sourcing—a newdimension of globalization. By introducing this link of retailertransformation and trade into the literature, we hope to spura new line of research that is timely in light of the trade,development and globalization debates in developing countries.     

Focused,intense and long-term: evidence for granular ark (Anadara granosa) exploitation from late Holocene shell mounds of Blue Mud Bay,northern Australia

Explanatory frameworks relating to the appearance of shell mounds and the exploitation of molluscs (particularly the sand/mudflat bivalve Anadara granosa) during the late Holocene have tended to emphasise stasis and continuity. Very few analyses have adequately investigated the intensity of human predation during the mound period and the potential effects on the particular prey species. To this end, the biological and ecological characteristics of A. granosa, the dominant molluscan species for much of the known period of occupation in the region, are considered in detail, in combination with assessing the potential for human impact through predation via the measurement of 9106 A. granosa valves from three shell mounds. In explaining long-term economic change in this region of northern Australia, the focus has been placed on the analysis of relative changes and trends through time in prehistoric resource exploitation.     

The implications of information and communication technologies for sexualities and sexualised violences: Contradictions of sexual citizenships

A key aspect of globalisation, glocalisation and transnationalisation is the development of information and communication technologies (ICTs). Such technologies have major implications for sexualities and sexualised violences, and raise profound implications, contradictions and challenges for sexual citizenship. These implications include the affirmation of sexual citizenship, with the creation of new forms of sexual communities; and the denial of sexual citizenship, with the production of new opportunities for pornography, prostitution, sexual exploitation and sexual violences. The article goes on to focus particularly on the contradictory implications of ICTs for sexual citizenship. These include the simultaneous development of more democratic and diverse sexual communities, and sexual work and sexually violent work; movements beyond the exploiter/exploited dichotomy; complex relations of non-exploitative and sexual exploitation, commercialisation of sex, and enforcement of dominant sexual practices; blurring of the social, sexual–social, sexual and sexually violent, and of the sexually ‘real’ and sexually ‘representational’; closer association of sex with the ‘visual’ and the ‘representational’; increasing domination of the virtual as the mode(l) for non-virtual, proximate sociality, and possible impacts of the virtual on increased non-virtual, proximate sociality, even greater possibilities for ‘pure relationships’; shifts in sexual space and sexual place; development of new forms of transnational sexual citizenship, within shifting transpatriarchies. Contradictions between the scale of global material sex economies and the representation and reproduction of the sexual through ICTs appear to be increasing.     

The fish of Lake Titicaca: implications for archaeology and changing ecology through stable isotope analysis

Research on past human diets in the southern Lake Titicaca Basin has directed us to investigate the carbon and nitrogen stable isotopes of an important dietary element, fish. By completing a range of analyses on modern and archaeological fish remains, we contribute to two related issues regarding the application of stable isotope analysis of archaeological fish remains and in turn their place within human diet. The first issue is the potential carbon and nitrogen isotope values of prehistoric fish (and how these would impact human dietary isotopic data), and the second is the observed changes in the fish isotopes through time. Out of this work we provide quantitative isotope relationships between fish tissues with and without lipid extraction, and a qualitative analysis of the isotopic relationships between fish tissues, allowing archaeologists to understand these relationships and how these values can be applied in future research. We test a mathematical lipid normalization equation to examine whether future researchers will need to perform lipid extraction procedures for Lake Titicaca fish. We also analyze a number of aquatic plants to better understand the range of isotopic signatures of the Lake Titicaca ecosystem. We use these data to better understand prehistoric human diet and the role that fish may have played in the past as well as potential changes in local lake ecology through time.     

Record of the deep marine Clinocythereis australis Ayress and Swanson, 1991 (Ostracoda) from the upper Miocene Tambo River Formation,Gippsland Basin,Australia: Palaeo-oceanographic and biostratigraphic implications

A new species of Tertiary lungfish, Neoceratodus djelleh, is based on two well-preserved upper tooth plates, from Duaringa, Queensland. Both specimens are elongate and have curved mediolingual faces and poorly defined ridges, with little trace of crests or clefts on the flat occlusal surface. Each ridge is supported by a bony base which extends into a peak. Enameloid is present, showing growth lines without associated cusps on the labial surface. Another specimen from Billeroo Creek, South Australia, is referred to Neoceratodus cf. N. djelleh.     

The Shuidonggou site complex: new excavations and implications for the earliest Late Paleolithic in North China

The initial Late Paleolithic, said to appear between 40 and 30 kya in eastern Asia, is defined by the appearance of many innovations. These archaeological indicators include the appearance of more refined stone tool making techniques (e.g., include the appearance of blade and microblade technology), complex hearth construction, use of pigments and personal ornamentation, as well as worked faunal implements such as bone and antler tools. We report here new findings from a multidisciplinary research project conducted at the Shuidonggou (Choei-tong-keou) site complex in northern China, a series of localities that date from the initial Late Paleolithic to the Neolithic.     

Evolution of porosity, permeability and fluid pressure in dilatant faults post-failure: implications for fluid flow and mineralization

Mineralization of brittle fault zones is associated with sudden dilation, and the corresponding changes in porosity, permeability and fluid pressure, that occur during fault slip events. The resulting fluid pressure gradients cause fluid to flow into and along the fault until it is sealed. The volume of fluid that can pass through the deforming region depends on the degree of dilation, the porosity and permeability of the fault and wall rocks, and the rate of fault sealing. A numerical model representing a steep fault cutting through a horizontal seal is used to investigate patterns of fluid flow following a dilatant fault slip event. The model is initialized with porosity, permeability and fluid pressure representing the static mechanical state of the system immediately after such an event. Fault sealing is represented by a specified evolution of porosity, coupled to changes in permeability and fluid pressure, with the rate of porosity reduction being constrained by independent estimates of the rate of fault sealing by pressure solution. The general pattern of fluid flow predicted by the model is of initial flow into the fault from all directions, followed by upward flow driven by overpressure beneath the seal. The integrated fluid flux through the fault after a single failure event is insufficient to account for observed mineralization in faults; mineralization would require multiple fault slip events. Downward flow is predicted if the wall rocks below the seal are less permeable than those above. This phenomenon could at least partially explain the occurrence of uranium deposits in reactivated basement faults that cross an unconformity between relatively impermeable basement and overlying sedimentary rocks.     

Constraining the rate and extent of mantle serpentinization from seismic and petrological data: implications for chemosynthesis and tectonic processes

We used seismic velocity as a proxy for serpentinization of the mantle, which occurred beneath thinned but laterally continuous continental crust during continental break up, prior to opening of the Atlantic Ocean. The serpentinized sub‐continental mantle is now exhumed, beneath the Iberia Abyssal Plain and was accessed by scientific drilling on Ocean Drilling Program legs 149 and 173. Chromatographic modelling of kinetically limited transport of the serpentinization front yields a front displacement of 2197 ± 89 m, a time‐integrated fluid flux of 1098 ± 45 m³ m^?2 and a Damköhler number of 6.0 ± 0.2. Whether either surface reaction or chemical transport limit the rate of reaction, we calculate timescales for serpentinization of approximately 10⁵–10⁶ years. This yields time‐average fluid flux rates for H₂O, entering and reacting with the mantle, of 60–600 mol m^?2 a^?1 and for CH₄, produced as a by‐product of oxidation of Fe⁺⁺ to magnetite and exiting the mantle, of 0.55–5.5 mol m^?2 a^?1. This equates to a CH₄‐flux of 0.18–1.8 Tg a^?1 for coeval serpentinization of the mantle that was exhumed west of Iberia. This represents 0.03–0.3% of the present‐day annual CH₄‐flux from all sources and a higher fraction of pre‐anthropogenic (lower) CH₄ levels. CH₄ released by serpentinization at or beneath the seafloor could provide substrate for biological chemosynthesis and/or promote gas‐hydrate formation. Finally, noting its volumetric extent and rapidity (<10⁶ years), we interpret serpentinization to be a reckonable component of tectonic processes, contributing both diapiric and expansional forces and helping to ‘lubricate’ extensional processes. Given its anisotropic permeability, actively deforming serpentinite might impede melt migration which may be of interest, given the apparent lack of melt in some rifted margins.     

South African palaeoenvironments during marine oxygen isotope stage 4: a context for the Howiesons Poort and Still Bay industries

Spanning the period from ∼74–58 ka, and being broadly coeval with marine oxygen isotope stage 4 (MIS 4), the Still Bay and Howiesons Poort industries represent important phases in the development of the material culture of early modern humans. How and why these industries occurred when they did, however, remain matters for speculation. A key element of this debate has been the question of what role environmental change during the early stages of the last glacial period may have had on influencing human activity. Unfortunately, well-dated palaeoenvironmental evidence from this period is limited, and the debate has, out of necessity, been driven by the application of conceptual models of environmental change, many of which associate colder and warmer global climates with increased aridity and humidity respectively. In this paper, the regional marine and terrestrial evidence is synthesised to create an evidence-based palaeoenvironmental context. Based on the information available to date, it appears that rather than being characterised by dry conditions, MIS 4 was a period of relatively cool, moist climates, the ubiquity of which transcends the modern regional climate boundaries. It is suggested that orbital parameters at this time created greater interaction between tropical and temperate circulation systems, bringing more moisture to the subcontinent. These findings highlight the distinct nature of southern African climate systems, and caution against the application extra-regional conceptual models or inferring linear relationships with polar records.     

A method for estimating edge length from flake dimensions: use and implications for technological change in the southern African MSA

This paper presents a method for estimating edge length from flake dimensions. Comparison of estimated values with data from measured flake edges demonstrates the robusticity of the method. Building on the work of Braun (Braun, D.R., 2005. Examining flake production strategies: examples from the Middle Paleolithic of Southwest Asia. Lithic Technology 30, 107–125; Braun, D.R., Harris, J.W.K., 2003. Technological developments in the Oldowan of Koobi Fora: innovative techniques of artifact analysis and new interpretations of Oldowan behavior, in Mora, R., de la Torre, I. (Eds.), Oldowan: Rather More than Smashing Stones. Treballs d’ Arqueologia 9, pp. 132–144) this estimate is used to generate an edge length to mass value for complete flakes—taken to be a proxy for flaking efficiency. It is shown that this value is useful in tracking the onset, variability and decline of a well known technological phase—the Howiesons Poort of South Africa. The results suggest that the Howiesons Poort was a time in which flaking efficiency was emphasised. Furthermore, comparison of upper limits of edge to mass values for different raw materials may provide an insight into changes in raw material selection.