The endangered Sonoran topminnow: Examination of species and ESUs using three mtDNA genes

There has been controversy over the species status of Sonoran topminnows and debate about the presence of ESUs in the Gila topminnow. From examination of sequence variation at 2626 base pairs over three mtDNA genes, we found a 29 (1.1%) nucleotide genetic difference between Gila and Yaqui topminnows. This provides strong support that these two taxa are separate species, Poeciliopsis occidentalis (Gila topminnow) and P. sonoriensis (Yaqui topminnow) and have been separated for approximately one million years. All the Gila topminnows within Arizona have the same sequence for the three mtDNA genes, that is, there is not reciprocal monophyly for mtDNA sequence data for the two previously designated ESUs. However, evidence of the unique habitat for Monkey Spring, its long-term isolation from other Gila topminnow habitats, and the presence of unique fish and invertebrate taxa in Monkey Spring support the designation of the Monkey Spring topminnows as an ESU. Finally, theoretical considerations using molecular data and estimates of heterozygosity and genetic distance for nuclear genes between populations of the Gila topminnow show that the lack of mtDNA variation is not inconsistent with the level and pattern of nuclear genetic variation observed.     

Connecting local environmental sequences to global climate patterns: evidence from the hominin-bearing Hadar Formation, Ethiopia

Central to the debate surrounding global climate change and Plio-Pleistocene hominin evolution is the degree to which orbital-scale climate patterns influence low-latitude continental ecosystems and how these influences can be distinguished from regional volcano-tectonic events and local environmental effects. The Pliocene Hadar Formation of Ethiopia preserves a record of hominin paleoenvironments from roughly 3.5 to 2.2 Ma at a temporal resolution relevant to evolutionary change within hominins and other taxa. This study integrates the high-resolution sedimentological and paleontological records at Hadar with climate proxies such as marine core isotope, dust, and sapropel records. Consistent cycling observed both between and within fluvial and lacustrine depositional environments prior to 2.9 Ma at Hadar appears to be predominantly climatic in nature. In contrast a significant change in depositional facies after 2.9 Ma to sequences dominated by conglomerate cut-and-fill cycles indicates a strong tectonic signature related to regional developments in the Main Ethiopian Rift. While specific events seen in marine proxy records may have parallels in the Hadar environmental archive, their overall patterns of high versus low variability may be even more relevant. For example, periods of relatively high-amplitude climate oscillations between 3.15 and 2.95 Ma may be linked to noted size-related morphological changes within the Hadar Australopithecus afarensis lineage and a significant increase in more arid-adapted bovid taxa. Increased aridity in East Africa during this period is also indicated by peaks in eolian dust in the marine core record. Conversely, the dominant lacustrine phase at Hadar ca. 3.3 Ma coincides with the least variable period in several climate proxy records, including marine core foraminifera delta(18)O values and eolian dust concentration. This phase is also coeval with low insolation variability and a very distinct and significant long-term period of low dust percentage in circum-Africa marine cores.     

Relationships Between Metal Concentrations in Human Hair and in Soil,Road Dust,and Rice

The relationships between metal contents in soil, road dust, and rice, and in human hair from a rural area of China were observed for Cr, Cu, Mn, Ni, Pb, and Zn. The results showed that the mean concentrations of Mn in human hair were higher than the highest reference value. The concentrations of Cr, Cu, Ni, and Zn in soil and road dust were usually higher than their background values. The enrichment factors indicated that the determined metals in soil and road dust were usually derived from natural sources. Chromium, Pb, and Zn in soils and road dusts from several sites were slightly influenced by anthropogenic sources. The regression analyses showed that positive relationships usually exist between the concentrations of the determined metals in rice and in human hair as well as in soil and in human hair. However, relationships between metal concentrations in road dust and in human hair were less obvious. The study demonstrated that human hair was an applicable biomonitor of metal concentrations in rice, soil, and road dust from a rural area in China. Metal concentrations in local human hair could be used to predict contamination levels of metals in rice and soil.     

Village Drift and Riverine Settlement: Modeling Akimel O'odham Land Use

Regular unscheduled movements of rancherías within a confined area or settlement district result in the phenomenon described as "village drift," a process whereby a settlement may change its location gradually by several kilometers over a period of years. This article presents a model of village drift based on data acquired from recent archaeological and geomorphological field studies and archival research on the Akimel O'odham, the Gila River Pima of south-central Arizona. The model provides an excellent example of human ecodynamics---an emerging landscape perspective that emphasizes the coevolution of humans and their ecosystem---with implications for understanding prehistoric and historic settlement in desert riverine environments.     

The magnitude and origin of European-American admixture in the Gila River Indian Community of Arizona: a union of genetics and demography.

Complementary genetic and demographic analyses estimate the total proportion of European-American admixture in the Gila River Indian Community and trace its mode of entry. Among the 9,616 residents in the sample, 2,015 persons claim only partial Native American heritage. A procedure employing 23 alleles or haplotypes at eight loci was used to estimate the proportion of European-American admixture, m(a), for the entire sample and within six categories of Caucasian admixture calculated from demographic data, md. The genetic analysis gave an estimate of total European-American admixture in the community of 0.054 (95% confidence interval [CI] .044-.063), while an estimate from demographic records was similar, .059. Regression of m(a) on md yielded a fitted line m(a) = .922md, r = .959 (P = .0001). When total European-American admixture is partitioned between the contributing populations, Mexican-Americans have provided .671, European-Americans .305, and African-Americans .023. These results are discussed within the context of the ethnic composition of the Gila River Indian Community, the assumptions underlying the methods, and the potential that demographic data have for enriching genetic measurements of human admixture. It is concluded that, despite the severe assumptions of the mathematical methods, accurate, reliable estimates of genetic admixture are possible from allele and haplotype frequencies, even when there is little demographic information for the population.     

Diatom changes in two Uinta mountain lakes,Utah, USA: responses to anthropogenic and natural atmospheric inputs

Diatom assemblages in sediments from two subalpine lakes in the Uinta Mountains, Utah, show asynchronous changes that are related to both anthropogenic and natural inputs of dust. These lakes are downwind of sources of atmospheric inputs originating from mining, industrial, urban, agricultural and natural sources that are distributed within tens to hundreds of kilometers west and south of the Uinta Mountains. Sediment cores were retrieved from Marshall and Hidden lakes to determine the impacts of atmospheric pollution, especially metals. Paleolimnological techniques, including elemental analyses and ²¹⁰Pb and ^239+240Pu dating, indicate that both lakes began receiving eolian inputs from anthropogenic sources in the late 1800s with the greatest increases occurring after the early 1900s. Over the last century, sediments in Marshall Lake, which is closer to the Wasatch Front and receives more precipitation than Hidden Lake, received twice the concentrations of metals and phosphorus as Hidden Lake. Comparison of diatom and elemental data reveals coeval changes in geochemistry and diatom assemblages at Marshall Lake, but not at Hidden Lake; however, a major shift in diatom assemblages occurs at Hidden Lake in the seventeenth century. The change in diatoms at Marshall Lake is marked by the near disappearance of Cyclotella stelligera and C. pseudostelligera and an increase in benthic, metal-tolerant diatoms. This change is similar to changes in other lakes that have been attributed to metal pollution. The marked change in diatom assemblages at Hidden Lake indicates a shift in lake-water pH from somewhat acidic to circumneutral. We hypothesize that this change in pH is related to drought-induced changes in input of carbonate-rich desert dust.     

Microbial diversity of eolian dust sources from saline lake sediments and biological soil crusts in arid Southern Australia

While microbial communities of aerosols have been examined, little is known about their sources. Nutrient composition and microbial communities of potential dust sources, saline lake sediments (SLS) and adjacent biological soil crusts (BSC), from Southern Australia were determined and compared with a previously analyzed dust sample. Multivariate analyses of fingerprinting profiles indicated that the bacterial communities of SLS and BSC were different, and these differences were mainly explained by salinity. Nutrient concentrations varied among the sites but could not explain the differences in microbial diversity patterns. Comparison of microbial communities with dust samples showed that deflation selects against filamentous cyanobacteria, such as the Nostocales group. This could be attributed to the firm attachment of cyanobacterial filaments to soil particles and/or because deflation occurs mainly in disturbed BSC, where cyanobacterial diversity is often low. Other bacterial groups, such as Actinobacteria and the spore-forming Firmicutes, were found in both dust and its sources. While Firmicutes-related sequences were mostly detected in the SLS bacterial communities (10% of total sequences), the actinobacterial sequences were retrieved from both (11-13%). In conclusion, the potential dust sources examined here show highly diverse bacterial communities and contain nutrients that can be transported with aerosols. The obtained fingerprinting and sequencing data may enable back tracking of dust plumes and their microorganisms.     

Miocene to recent eolian dust record from the Southwest Pacific Ocean at 40° S latitude

A 14-meter long pelagic clay core recovered at Marlin Rise (40°00.531′S, 154°2.601′W; 4775 m water depth) in the Southwest Pacific Basin contains a record of eolian dust deposited since the early Miocene. Downcore analysis of detrital minerals reveals a dominantly eolian signature with relatively constant proportions of quartz, feldspar and illite and trace amounts of chlorite, kaolinite and smectite, consistent with a continental (loess-like) source region. Fish tooth Sr isotope stratigraphy reveals the base of the core to be 17.5 Ma, with low sedimentation rates (< 0.5 mm/kyr LSR) indicated for the interval 17.5 to 10 Ma; several hiatuses in deposition appear to be present upcore, but are beyond the age resolution of the fish teeth stratigraphy. These intervals are revealed as apparent discontinuities in the Sr isotope record, accompanied by pulses of anomalously rapid sedimentation at ~ 10 Ma, 6.7 Ma and 4.1 Ma. Bulk mass accumulation rates (MAR) are calculated at ~ 10 mg/cm²/kyr over the last 4 Myr, consistent with previously estimated Quaternary eolian flux rates to this part of the Pacific. Nd, Pb and Sr radiogenic isotopic compositions of the detrital mineral extract (< 38 µm) show no trends with age, while ⁴⁰Ar/³⁹Ar ages show an upcore younging trend (~180 Ma to ~150 Ma), in concert with a slight coarsening of eolian grain-size distributions. These ages likely reflect mixing of Mesozoic illite-dominated clay from at least two continental source areas: southeastern Australia (Murray–Darling Basin/Lake Eyre Basin) and New Zealand (South Island). The data indicate remarkable constancy of continental eolian sources exposed to weathering and dispersal at this latitude during the Neogene.     

Factors Influencing the Health Behaviour of Indigenous Australians: Perspectives from Support People

Disparities between the health of Indigenous and non-Indigenous populations continue to be prevalent within Australia. Research suggests that Indigenous people participate in health risk behaviour more often than their non-Indigenous counterparts, and that such behaviour has a substantial impact on health outcomes. Although this would indicate that reducing health risk behaviour may have positive effects on health outcomes, the factors that influence Indigenous health behaviour are still poorly understood. This study aimed to interview people who support Indigenous groups to gain an understanding of their views on the factors influencing health behaviour within Indigenous groups in Western Australia. Twenty nine people participated in the study. The emergent themes were mapped against the social ecological model. The results indicated that: (1) culture, social networks, history, racism, socioeconomic disadvantage, and the psychological distress associated with some of these factors interact to affect health behaviour in a complex manner; (2) the desire to retain cultural identity and distinctiveness may have both positive and negative influence on health risk behaviour; (3) strong social connections to family and kin that is intensified by cultural obligations, appears to affirm and disrupt positive health behaviour; (4) the separation between Indigenous and non-Indigenous social connection/networks that appeared to be fostered by marginalisation and racism may influence the effect of social networks on health behaviour; and (5) communication between Indigenous and non-Indigenous people may be interrupted by distrust between the groups, which reduces the influence of some non-Indigenous sources on the health behaviour of Indigenous people.     

Human occupancy as a source of indoor airborne bacteria

Exposure to specific airborne bacteria indoors is linked to infectious and noninfectious adverse health outcomes. However, the sources and origins of bacteria suspended in indoor air are not well understood. This study presents evidence for elevated concentrations of indoor airborne bacteria due to human occupancy, and investigates the sources of these bacteria. Samples were collected in a university classroom while occupied and when vacant. The total particle mass concentration, bacterial genome concentration, and bacterial phylogenetic populations were characterized in indoor, outdoor, and ventilation duct supply air, as well as in the dust of ventilation system filters and in floor dust. Occupancy increased the total aerosol mass and bacterial genome concentration in indoor air PM(10) and PM(2.5) size fractions, with an increase of nearly two orders of magnitude in airborne bacterial genome concentration in PM(10). On a per mass basis, floor dust was enriched in bacterial genomes compared to airborne particles. Quantitative comparisons between bacterial populations in indoor air and potential sources suggest that resuspended floor dust is an important contributor to bacterial aerosol populations during occupancy. Experiments that controlled for resuspension from the floor implies that direct human shedding may also significantly impact the concentration of indoor airborne particles. The high content of bacteria specific to the skin, nostrils, and hair of humans found in indoor air and in floor dust indicates that floors are an important reservoir of human-associated bacteria, and that the direct particle shedding of desquamated skin cells and their subsequent resuspension strongly influenced the airborne bacteria population structure in this human-occupied environment. Inhalation exposure to microbes shed by other current or previous human occupants may occur in communal indoor environments.     

Structural and dynamical patterns on online social networks: the Spanish May 15th movement as a case study

The number of people using online social networks in their everyday life is continuously growing at a pace never saw before. This new kind of communication has an enormous impact on opinions, cultural trends, information spreading and even in the commercial success of new products. More importantly, social online networks have revealed as a fundamental organizing mechanism in recent country-wide social movements. In this paper, we provide a quantitative analysis of the structural and dynamical patterns emerging from the activity of an online social network around the ongoing May 15th (15M) movement in Spain. Our network is made up by users that exchanged tweets in a time period of one month, which includes the birth and stabilization of the 15M movement. We characterize in depth the growth of such dynamical network and find that it is scale-free with communities at the mesoscale. We also find that its dynamics exhibits typical features of critical systems such as robustness and power-law distributions for several quantities. Remarkably, we report that the patterns characterizing the spreading dynamics are asymmetric, giving rise to a clear distinction between information sources and sinks. Our study represents a first step towards the use of data from online social media to comprehend modern societal dynamics.     

Interaction of Gila monster venom with VIP receptors in intestinal epithelium of human. A comparison with rat

Gila monster venom (1-300 micrograms/ml) is shown to inhibit completely the binding of [125I]VIP to human and rat intestinal epithelial cell membranes. In both models, the venom inhibits [125I]VIP binding and stimulates adenylate cyclase with a maximal efficiency that is similar to that of VIP and a potency that is 10000-50000 times lower than that of the peptide, on a weight basis. At maximal doses, VIP and Gila monster venom do not exert an additive effect on adenylate cyclase, suggesting that the activation of the enzyme by the venom occurs through VIP receptors. As is the case for VIP, adenylate cyclase activation by Gila monster venom requires the presence of GTP in the incubation medium. Finally, no VIP-like immunoreactivity was detected in the venom using an antiserum raised against mammalian VIP. All these data suggest the presence in the venom of the Gila monster, of a new substance which behaves as a VIP agonist in human as well as rat intestine.     

Self-consistent quasineutral dust structures

Distributions of the dusty plasma parameters (electron, ion, and dust densities; dust grain charge; and ion drift velocity) in quasineutral dust structures whose dimensions are much greater than the mean free path of the ions in their interactions with neutral particles are calculated numerically under conditions such that ionization sources are located outside the structures. Planar, cylindrical, and spherical structures are investigated. It is shown that static equilibrium structures are governed by a single (basic) parameter: the electrostatic potential drop between the center of the structure and its boundary. It is found that the maximum value of the basic parameter (in energy units) does not exceed the electron temperature. The basic parameter also determines the total number of dust grains in the structure and the power of external ionization sources that are necessary to sustain this structure. The fact that the basic parameter varies within a limited range allows one to consider all the possible structures with a given dimensionality (planar, cylindrical, and spherical).     

Plains History and Cultural Anthropology

Abstract

Recent cutbacks in research funding and the burgeoning population of anthropology graduate departments may soon force cultural anthropologists to recognize what their archaeological colleagues have long known: their own “backyard” is a field for fertile research. Specifically, cultural anthropologists may turn increasingly to using long-neglected data sources - rich in documentation - on Anglo-Saxon America. This paper briefly investigates some reasons for the study of American historical data and presents a preliminary analysis of some data.     

Fibrinolytic activity of Bacillus mesentericus strains

Two Bacillus mesentericus strains with a high activity of proteolytic enzymes having the thrombolytic action were selected from a group of its collection strains. The effect of different carbon sources on the synthesis of proteases was studied. A growth medium containing potato broth (10%), peptone (0.5%) and lactose (0.5%) allowed one to obtain a cultural broth dissolving human blood clots within 2.5 to 3 hours in experiments in vitro.     

Cross-Checking Different Sources of Mobility Information

The pervasive use of new mobile devices has allowed a better characterization in space and time of human concentrations and mobility in general. Besides its theoretical interest, describing mobility is of great importance for a number of practical applications ranging from the forecast of disease spreading to the design of new spaces in urban environments. While classical data sources, such as surveys or census, have a limited level of geographical resolution (e.g., districts, municipalities, counties are typically used) or are restricted to generic workdays or weekends, the data coming from mobile devices can be precisely located both in time and space. Most previous works have used a single data source to study human mobility patterns. Here we perform instead a cross-check analysis by comparing results obtained with data collected from three different sources: Twitter, census, and cell phones. The analysis is focused on the urban areas of Barcelona and Madrid, for which data of the three types is available. We assess the correlation between the datasets on different aspects: the spatial distribution of people concentration, the temporal evolution of people density, and the mobility patterns of individuals. Our results show that the three data sources are providing comparable information. Even though the representativeness of Twitter geolocated data is lower than that of mobile phone and census data, the correlations between the population density profiles and mobility patterns detected by the three datasets are close to one in a grid with cells of 2×2 and 1×1 square kilometers. This level of correlation supports the feasibility of interchanging the three data sources at the spatio-temporal scales considered.     

新疆于田流水墓地青铜时代人类牙齿非测量性状

我国新疆地区自古以来即是东西方文明相互交融的摇篮,以往的考古学、体质人类学研究表明,该区域内不同文化之间的互通有无早在我国青铜-早期铁器时代便已经发生。关于这种交流与融合产生的原因,目前学术界仍未有定论。新疆于田流水墓地(2950±50 BP)是由中国社会科学院考古研究所于2003-2005年主持发掘的青铜时代墓葬群,该墓地共发掘墓葬65座,被视为是昆仑山北麓发现的最早人类文化遗存。本文从采集自流水墓地108例人骨标本的19项牙齿非测量性状研究入手,将其与欧亚大陆范围内的古今人群进行比较研究,并进行史密斯生物学距离的计算以及主成分分析。结果表明:生活在新疆流水地区的古代人类与南西伯利亚地区、日本绳纹、阿富汗/巴基斯坦、中国姜家梁地区人群之间在牙齿非测量性状方面存在某种程度上的相似性,这或许可以说明至少在3000年前,我国新疆西南部地区可能已经存在了东西方的人群迁徙。     

Comparison of Source Identification of Metals in Road-Dust and Soil

Source identification of toxic metals is very critical for pollution prevention and human health protection. Many studies only use either road dust metal data or soil metal data to evaluate metal contamination and identify pollution sources, and this may lead to the exclusion of some important information. In this study, the differences of metal spatial distribution and source identification between road dust and associated soil in an industrial area were investigated.

Results indicate the metal concentrations in road dust were generally higher than those in soil. Based on the average concentrations, the order for dust metal concentrations was Fe>>Zn>>Pb>Cu>Cr>Ni. The order for soil metal concentrations was slightly different, namely Fe>>Zn>>Cu～Pb>Ni>Cr. The spatial distributions of metals in the road dust were very different from those in the soil, except for Fe. The GIS results indicate that elevated levels of Fe, Zn, and Pb were present in road dust near a steel plant. High concentrations of Cu, Cr, and Ni appeared at a road intersection. Elevated metal concentrations of Fe, Zn, Pb, Cu, and Cr were present in soil around the steel plant. A coal-fired power plant did not seem to be a significant metal source in this study. Significant correlations for dust metals imply that these were well mixed in the study area. The metal sources identified by PCA with soil metal data were obviously different from those identified with road dust metal data. When road dust metal data were used, the changes of PCA analyzed areas slightly influenced the source identification. The PCA results were obviously influenced by changes of analyzed areas when soil metal data were used.     

Fire regimes in north-eastern Cambodian monsoonal forests, with a 9300-year sediment charcoal record

Aim To provide insights concerning changes in fire regime in north‐eastern Cambodia over the course of the Holocene, and discuss implications of these long‐term data for fire management in the present day. Location Southern Ratanakiri Province, north‐eastern Cambodia. The lake sites sampled here are embedded in a mosaic of mostly open, strongly deciduous dipterocarp forest, with patches of riparian, semi‐evergreen and evergreen forests. Methods Background information on the environmental and cultural setting comes from informal and semi‐structured interviews of local villagers to determine present‐day burning patterns and customs. Primary data come from analysis of changes in charcoal concentration within sediments from small, closed basin lakes. Charcoal data are compared with changes in pollen and sediment physical characteristics, and to present‐day local customs, to infer or speculate on changes in human use of fire. Results Interviews with local people reveal two general types of human‐induced fires, one type for swidden cultivation in denser forests, the other type for clearance of ground layer vegetation in more open forests. A 9300‐year sediment record of microscopic charcoal deposition shows strongest fire activity ending by 8000 years ago, and the remainder of the early Holocene reflecting a strong summer monsoon and low fire activity. Beginning c. 5500 years ago, forest disturbance and fire activity increased. A subtle change in the record at c. 3500 years ago and more marked change at c. 2500 years ago suggest that fire frequency, and maybe human control over fire, became more important during that period and continuing up to the present. Main conclusions With this type of empirical data from only one site, it is impossible to make accurate conclusions about long‐term human impacts from burning. However, this record does show that present‐day charcoal input from fire activity is among the lowest for the last 9300 years. Considered together with other changes in the record and with present‐day customs, there is a suggestion that anthropogenic fire is an adaptation to the monsoonal environment, and may be conservative of forest cover in open forest formations. This long‐term perspective on the role of indigenous land‐use customs in landscape evolution should be considered in forest management and biological conservation, as it differs significantly from the traditional rationale for policies of fire suppression in tropical forests.     

Anatomy, internal heterogeneities, and early fracture network of a Pleistocene carbonate coastal dune (Rejiche Formation, southeastern Tunisia)

Although eolian deposits are known to record the dominant winds, secondary conditions such as wind reversals during wintertime can also be observed in the petrographic composition and facies succession. Thus, eolian deposits are used here as a local paleoclimatic proxy. The spatial distribution of the depositional facies, early diagenetic imprints, and early fracture network of a coastal Pleistocene eolian ridge in southeastern Tunisia is described using a small-scale GIS model. Facies analysis indicates that coastal dune systems record seasonal cycles. The fracture density and directions are strongly influenced by the depositional facies type. Laminated facies present a higher fracture density compared to more homogeneous facies and show only one major fracture direction, while the more homogeneous facies display a bimodal distribution. Such a difference between these two groups is explained by the heterogeneous distribution of the early calcite cement within the laminated facies. No tectonic activity or overlying strata have affected the Pleistocene dunes under study. Therefore, the mechanism responsible for the fractures could only be related to the own weight of the eolianite and to its internal or underlying lithologic heterogeneity.