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Early and Middle Pleistocene Faunal and Hominins Dispersals through Southwestern Asia
This review summarizes the paleoecology of the Early and Middle Pleistocene of southwestern Asia, based on both flora and fauna, retrieved from a series of âwindowsâ provided by the excavated sites. The incomplete chrono-stratigraphy of this vast region does not allow to accept the direct chronological correlation between the available sites and events of faunal and hominin dispersals from Africa. It also demonstrates that hominins survived in a mixed landscape of open parkland with forested surrounding hills. In addition, the prevailing environmental conditions are not sufficient to explain successful adaptations to new ecological niches away from the African savanna of the bearers of âcore and flakeâ and the Acheulian industries, The differences in knapping and secondary shaping of stone artifacts probably reflect the learned traditions of different groups of hominins. The current distribution of lithic industries across Eurasia is undoubtedly incomplete due to lack of cultural continuities as well as paucity of field research in several sub-regions. This observation supports the contention that what we view as a constant stream of migrants was actually interrupted many times. The continuous occupation of southwestern Asia by the makers of the Acheulian is in contrast with neighboring regions such as the Iranian plateau and Eastern Europe. A more complex model is required to explain the recorded Eurasian archaeologicalâcultural mosaic.Anthropolog
Ecological pleiotropy and indirect effects alter the potential for evolutionary rescue
Invading predators can negatively affect naĂŻve prey populations due to a lack of evolved defenses. Many species therefore may be at risk of extinction due to overexploitation by exotic predators. Yet the strong selective effect of predation might drive evolution of imperiled prey toward more resistant forms, potentially allowing the prey to persist. We evaluated the potential for evolutionary rescue in an imperiled prey using Gillespie ecoâevolutionary models (GEMs). We focused on a system parameterized for protists where changes in prey body size may influence intrinsic rate of population growth, space clearance rate (initial slope of the functional response), and the energetic benefit to predators. Our results show that the likelihood of rescue depends on (a) whether multiple parameters connected to the same evolving trait (i.e., ecological pleiotropy) combine to magnify selection, (b) whether the evolving trait causes negative indirect effects on the predator population by altering the energy gain per prey, (c) whether heritable trait variation is sufficient to foster rapid evolution, and (d) whether prey abundances are stable enough to avoid very rapid extinction. We also show that when evolution fosters rescue by increasing the prey equilibrium abundance, invasive predator populations also can be rescued, potentially leading to additional negative effects on other species. Thus, ecological pleiotropy, indirect effects, and system dynamics may be important factors influencing the potential for evolutionary rescue for both imperiled prey and invading predators. These results suggest that bolstering trait variation may be key to fostering evolutionary rescue, but also that the myriad direct and indirect effects of trait change could either make rescue outcomes unpredictable or, if they occur, cause rescue to have side effects such as bolstering the populations of invasive species
Mortality in the Bedouin Population and Proximity to a Regional Industrial Complex
Background: The study was initiated by public concern about exposure to an industrial park (IP) emission. The study examined whether mortality in the Bedouin population in the southern part of Israel is associated with the residential distance to the IP.Material and Methods: Ecological study during 1995â2001 included the entire Bedouin population. Mortality data was obtained from the Central Bureau of Statistics. As an indirect measurement of exposure we used residential distance to the IP (with 20 km radius as a cut-of-point) based on residentsâ complaints about odor related to the IP. Differences in mortality rates by distance were assessed by the Mantel-Haenszel relative risk (M-H RR) within the 95% CI. The country Arab population served as a reference for calculation of the age-adjusted standardized mortality ratio (SMR).Results: Increased mortality rates due to symptoms/ill-defined conditions and non-external causes were observed in the Bedouin population of both sexes, residing up to 20 km from the IP, compared to those living in more remote areas. Corresponding M-H RR (plus 95% CI) were 1.66 (1.17â2.36), 1.24 (1.06â1.44) in females, and 1.55 (1.15â2.10), 1.32 (1.15â1.52) in males.Conclusions: The study results suggest an association between residential proximity to the regional IP and increased mortality rates in the Negev Bedouin population. These findings have been accepted by the authorities as an issue for community health protection
Knowledge, Attitudes, and Practice among Women and Doctors Concerning the Use of Folic Acid
Background and Objective. Daily folic acid intake, prior to conception and in early pregnancy, significantly reduces neural tube defects (NTDs). We compared folic acid consumption among Jewish and Bedouin women and the recommendations of family physicians and gynecologists.
Methods. We compared 64 Muslim Bedouin women and 65 Jewish women. We also compared 39 gynecologists and 60 family physicians. Results. Fifty-one Jewish women (78.5%) took folic acid during pregnancy, but only seven (10.8%) before conception. Sixty Bedouin women (93.75%) took folic acid during pregnancy, but only four (6.25%) before conception (P < .05). Five Jewish women (7.7%) and two Bedouin women (3.1%) took folic acid three months before conception. Thirty-three gynecologists (87%) recommend preconception folic acid compared with thirty-six family physicians (60%) (P < .05). Conclusions. The majority of women use folic acid during pregnancy, but only few do so to prevent NTDs. There is a significant difference between doctors' recommendations and actual practice
Revisiting the Question of Neandertal Regional Variability: a View from the RhĂŽne Valley Corridor
We compared the dental assemblage of the RhĂŽne Valley corridor (RVC) with that of European Neandertals dating to MOIS 7â4 using two linear measurements and three indices. To test if the RVC population was significantly different from Western European Neandertals, we preformed a multi-tiered approached. First, we tested for the normality of the variables using a Shapiro-Wilks test. If the variables were normal, a stepwise Discriminant Function Analysis (DFA) (using Mahalanobis distances) was performed for the normally distributed variables. DFA uses correlation metrics to address weight combinations of variables and emphasizes between group variation while minimizing within group variation. Results show that there is no distinction between the RVC population and other Neandertals except for the Crown Module index of the upper canine. However, the presence of a single significant result does not provide evidence for a local RVC variant within the Neandertal population. These results are supported by evidence from archaeological analysis of this region. We propose that the high genetic control for dental size and shape may account for the reduced ability to distinguish between subpopulation groups based on dental dimensions in groups with small effective size such as the Neandertals
Does scale matter? A systematic review of incorporating biological realism when predicting changes in species distributions
Background
There is ample evidence that biotic factors, such as biotic interactions and dispersal capacity, can affect species distributions and influence speciesâ responses to climate change. However, little is known about how these factors affect predictions from species distribution models (SDMs) with respect to spatial grain and extent of the models.
Objectives
Understanding how spatial scale influences the effects of biological processes in SDMs is important because SDMs are one of the primary tools used by conservation biologists to assess biodiversity impacts of climate change.
Data sources and study eligibility criteria
We systematically reviewed SDM studies published from 2003â2015 using ISI Web of Science searches to: (1) determine the current state and key knowledge gaps of SDMs that incorporate biotic interactions and dispersal; and (2) understand how choice of spatial scale may alter the influence of biological processes on SDM predictions.
Synthesis methods and limitations
We used linear mixed effects models to examine how predictions from SDMs changed in response to the effects of spatial scale, dispersal, and biotic interactions.
Results
There were important biases in studies including an emphasis on terrestrial ecosystems in northern latitudes and little representation of aquatic ecosystems. Our results suggest that neither spatial extent nor grain influence projected climate-induced changes in species ranges when SDMs include dispersal or biotic interactions.
Conclusions
We identified several knowledge gaps and suggest that SDM studies forecasting the effects of climate change should: 1) address broader ranges of taxa and locations; and 1) report the grain size, extent, and results with and without biological complexity. The spatial scale of analysis in SDMs did not affect estimates of projected range shifts with dispersal and biotic interactions. However, the lack of reporting on results with and without biological complexity precluded many studies from our analysis
Major congenital malformations and residential proximity to a regional industrial park including a national toxic waste site: An ecological study
BACKGROUND: Public concern about exposure to emissions from the regional industrial park (IP), including 17 chemical plants and the national industrial toxic waste site, initiated this study of the possible association between major congenital malformations (MCM) and residence near the IP in Israel's Southern District. METHODS: The study was conducted during the period 1995â2000 and included 63,850 deliveries. Data on deliveries and MCM detected at births were obtained from the regional medical center, and stratified by ethnicity and type of locality. As exposure indicator we used distance categories (proximal and distant) and predominant wind direction from the IP. Distance stratification was based on the geographical distribution of the localities and complaints about the odor related to IP emissions. Based on these complaints, localities up to 20 km from the IP were considered proximal to the IP. RESULTS: Average rates of MCM were 5.0% and 4.1% for Bedouin and Jewish newborns, respectively. The rate of MCM for Bedouin from proximal localities was significantly greater compared with distant localities (5.6% vs. 4.8%; RR = 1.17 with 95% CI: 1.04â1.29). In the proximal Bedouin permanent localities, the MCM rate reached 8.2 %, which was significantly higher than in distant areas (RR = 1.63, 95% CI: 1.39â1.80). Significant risk increase of central nervous system MCM was found in these localities, compared to distant ones (RR = 2.27, 95% CI: 1.44â3.60). Among newborns from the traditional tribal settlements, proximity to the IP was associated with increased rates of the following MCM: 1) all combined, 2) those associated with chromosomal abnormalities, and 3) those defined as "others unclassified MCM." Comparison of autosomal recessive disease rates by proximity to the IP in Bedouin newborns indicates that the observed increased risk of MCM is not explained by consanguineous marriages. The rates of MCM in the Jewish population were similar among "exposed" and "unexposed" inhabitants. CONCLUSION: Residential proximity to the IP is associated with increased rates of MCM among Arab-Beduin but not in Jewish populations. These observations indicate the need for public health protection of a vulnerable society in transition, although the relative importance of chemical exposure and health care utilization requires further study
Does scale matter? A systematic review of incorporating biological realism when predicting changes in species distributions
Background
There is ample evidence that biotic factors, such as biotic interactions and dispersal capacity, can affect species distributions and influence speciesâ responses to climate change. However, little is known about how these factors affect predictions from species distribution models (SDMs) with respect to spatial grain and extent of the models.
Objectives
Understanding how spatial scale influences the effects of biological processes in SDMs is important because SDMs are one of the primary tools used by conservation biologists to assess biodiversity impacts of climate change.
Data sources and study eligibility criteria
We systematically reviewed SDM studies published from 2003â2015 using ISI Web of Science searches to: (1) determine the current state and key knowledge gaps of SDMs that incorporate biotic interactions and dispersal; and (2) understand how choice of spatial scale may alter the influence of biological processes on SDM predictions.
Synthesis methods and limitations
We used linear mixed effects models to examine how predictions from SDMs changed in response to the effects of spatial scale, dispersal, and biotic interactions.
Results
There were important biases in studies including an emphasis on terrestrial ecosystems in northern latitudes and little representation of aquatic ecosystems. Our results suggest that neither spatial extent nor grain influence projected climate-induced changes in species ranges when SDMs include dispersal or biotic interactions.
Conclusions
We identified several knowledge gaps and suggest that SDM studies forecasting the effects of climate change should: 1) address broader ranges of taxa and locations; and 1) report the grain size, extent, and results with and without biological complexity. The spatial scale of analysis in SDMs did not affect estimates of projected range shifts with dispersal and biotic interactions. However, the lack of reporting on results with and without biological complexity precluded many studies from our analysis
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