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1.
Behavior of sixMacaca nemestrina mother-infant pairs was observed in two different environments; three pairs were part of a large group in a compound and three pairs were housed in individual laboratory cages. At weeks 14–15 of the infants' lives, group mothers were more retentive of their infants than caged mothers; group infants spent more time in ventral contact with mother and nursed more than did caged infants. The authors conclude that the greater dependence of an infant raised in a potentially dangerous group setting is due to a more protective mother rather than to a more fearful infant.This work was supported by grant no. FR 00166 from the National Institutes of Health, U. S. Public Health Service.Reprints may be obtained from:Primate Information Center, I-321 Health Sciences Building, University of Washington, Seattle, Washington 98105, U.S.A.  相似文献   

2.
Prakash , U., E. S. Barghoorn , and R. A. Scott . (Harvard U., Cambridge, Mass.) Fossil wood of Robinia and Gleditsia from the Tertiary of Montana . Amer. Jour. Bot. 49(7): 692–696. Illus. 1962.—Fossil woods representing 2 genera of the Leguminosae, Robinia Linnaeus and Gleditsia Clayton, have been identified from Tertiary beds in southern Montana. These woods are noteworthy owing to their exceptionally fine structural preservation and from the standpoint of their paleogeographical distribution. Neither genus now lives in the region of Montana.  相似文献   

3.
This study tested the efficacy of environmental DNA (eDNA) sampling to delineate the distribution of bull trout Salvelinus confluentus in headwater streams in western Montana, U.S.A. Surveys proved fast, reliable and sensitive: 124 samples were collected across five basins by a single crew in c. 8 days. Results were largely consistent with past electrofishing, but, in a basin where S. confluentus were known to be scarce, eDNA samples indicated that S. confluentus were more broadly distributed than previously thought.  相似文献   

4.
1. The changing climate is altering species distributions with consequences for population dynamics, resulting in winners and losers in the Anthropocene. 2. Agraulis vanillae, the gulf fritillary butterfly, has expanded its range in the past 100 years in the western U.S.A. Time series analysis is combined with species distribution modelling to investigate factors limiting the distribution of A. vanillae and to predict future shifts under warming scenarios. 3. Time series analyses from the western U.S.A. show that urban development has a positive association with year of colonisation (the host plant Passiflora is an ornamental in gardens). Colonisation was also associated positively and to a lesser extent with winter maximum temperatures, whereas a negative impact of minimum temperatures and precipitation was apparent on population growth rates after establishment. 4. Species distribution models vary by region. In the eastern U.S.A., the butterfly is primarily limited by minimum temperatures in the winter and host availability later in the season. Eastern U.S. projected expansion broadly follows the expectation of poleward distributional shifts, especially for the butterfly's maximum annual extent. Western U.S. distributions are limited by the host plant, which in turn is dependent on urban centres. Projected western U.S. expansion is not limited to a single direction and is driven by urban centres becoming more suitable for the host plant. 5. These results demonstrate the value of combining time series with spatial modelling, at the same time as incorporating biotic interactions, aiming to understand and predict shifting geographical ranges in the Anthropocene.  相似文献   

5.
This cultural case study investigates one U.S. psychosocial rehabilitation organization’s (Horizons) attempt to implement the recovery philosophy of the U.S. Recovery Movement and offers lessons from this local attempt that may inform global mental health care reform. Horizons’ “recovery-oriented” initiatives unwittingly mobilized stressful North American discourses of valued citizenship. At times, efforts to “empower” people diagnosed with schizophrenia to become esteemed self-made citizens generated more stressful sociocultural conditions for people whose daily lives were typically remarkably stressful. A recovery-oriented mental health system must account for people diagnosed with schizophrenia’s sensitivity to stress and offer consumers contextually relevant coping mechanisms. Any attempt to export U.S. mental health care practices to the rest of the world must acknowledge that (1) sociocultural conditions affect schizophrenia outcomes; (2) schizophrenia outcomes are already better in the developing world than in the United States; and (3) much of what leads to “better” outcomes in the developing world may rely on the availability of locally relevant techniques to address stress.  相似文献   

6.
The Alabama sturgeon (Scaphirhynchus suttkusi) is the rarest and most endangered sturgeon species in North America. Over an 8‐year period, the Alabama Division of Wildlife and Freshwater Fisheries, U.S. Army Corps of Engineers, and U.S. Fish and Wildlife Service cumulatively expended 2447 man‐days in efforts to collect Alabama sturgeon broodstock in an attempt to initiate a conservation propagation program. Out of nearly 29 000 fishes collected between March 1997 and May 2005, only five were Alabama sturgeon. Attempts to spawn and propagate these sturgeons were unsuccessful, and all have since died in captivity. In context with past collection efforts and anecdotal accounts, these results indicate that the Alabama sturgeon is becoming increasingly rare with the passage of time. Although there is evidence that some level of recruitment continued to occur in the Alabama River during the past decade, the increasing rarity of Alabama sturgeon suggests that mortality rates are exceeding recruitment.  相似文献   

7.
Neighborhood risk factors for obesity   总被引:1,自引:0,他引:1  
Objective: The goal of this study was to explore neighborhood environmental factors associated with obesity in a sample of adults living in a major U.S. metropolitan area. Research Methods and Procedures: This was a multi‐level study combining data from the U.S. Behavioral Risk Factor Surveillance System with data from the U.S. Census. A total of 15,358 subjects living in 327 zip code tabulation areas were surveyed between 1998 and 2002. The outcome was obesity (BMI >30), and independent variables assessed included individual level variables (age, education, income, smoking status, sex, black race, and Hispanic ethnicity), and zip code level variables (percentage black, percentage Hispanic, percentage with more than a high school education, retail density, establishment density, employment density, population density, the presence of a supermarket, intersection density, median household income, and density of fast food outlets). Results: After controlling for individual level factors, median household income [relative risk (RR) = 0.992; 95% confidence interval (CI) = 0.990, 0.994], population density (RR = 0.98; 95% CI = 0.972, 0.990), employment density (RR = 1.004; 95% CI = 1.001, 1.009), establishment density (RR = 0.981 95% CI = 0.964, 0.999), and the presence of a supermarket (RR = 0.893; 95% CI = 0.815, 0.978) were associated with obesity risk. Fast food establishment density was poorly associated with obesity risk. Discussion: Where one lives may affect obesity status. Given the influence of the presence of a supermarket on obesity risk, efforts to address food access might be a priority for reducing obesity.  相似文献   

8.
Elms (Ulmus procera andU. glabra) have been devastated in the UK by Dutch Elm disease. Because of lower temperatures in Northern Britain, relative to Southern Britain, elms have survived. In spite of this, elms have declined markedly in South-east Scotland over the past 20 years. Tree data relating to this decline are presented, together with a pollen calendar for the genus in S.E. Scotland and a tentative forecast for the disappearance of these two species in the region.  相似文献   

9.
The degradation and fragmentation of the northern Ethiopian highlands has resulted in frequent encounters of large carnivores with humans and their livestock. We interviewed 500 randomly selected households to estimate economic impact of livestock predation by spotted hyaena (Crocuta crocuta), leopard (Panthera pardus) and jackal (Canis aureus aureus) in the highlands of northern Ethiopia. The annual mean economic loss per household was approximately U.S.$ 20.2, about 7% of the average annual income of households in the area. Households surveyed reported losses of a total of 3122 livestock to hyaena, leopard and jackal predation over the past 5 years. This loss equated to a total financial loss of U.S.$ 50,381 . Livestock predation incidents of spotted hyaena, leopard and jackal demonstrated that spotted hyaena had a preference for dog, donkey, goat and sheep; leopard for goat, dog and sheep; and jackal for goat and sheep. Livestock predation of spotted hyaena and leopard were mainly during the night. We conclude that assessing depredation problems is important to develop actions for management of either livestock practices or wildlife conservation.  相似文献   

10.
Objective: The objective was to forecast BMI distribution in the U.S. population along with demographic changes based on past race‐, sex‐, and birth cohort‐specific secular trends. Research Methods and Procedures: We compiled data from 44,184 subjects from 4 National Health and Nutrition Examination Surveys (NHANES; 1971 to 2004). By race and sex, we fit regression models to create smoothed mean BMI curves by age for 1970 to 2010. Linking corresponding birth cohorts across age‐ and year‐specific mean BMI projections, we estimated the trajectory of relative BMI throughout each cohort's lifetime. These projections were validated using actual cohorts in the Nurses’ Health Study and Health Professionals Follow‐up Study. Combined with U.S. census, we predicted BMI distributions in 2010 and examined the joint impact of the obesity epidemic and population aging. Results: BMI secular trends in the past 3 decades differ significantly by birth cohort, sex, and race. If these trends continue, the prevalence of obesity is expected to reach 35%, 36%, 33%, and 55% in 2010 among white men, white women, black men, and black women, respectively, far from the Healthy People 2010 goal of 15%. Such forecasts translate into 9.3 million more obese adults 20 to 74 years of age than in 2000, 8.3 million of whom would be 50 years of age or older, and 8.5 million of whom would be white. The mean age among obese men and women is also expected to rise from 47 to 49 years among whites and from 43 to 44 years among blacks. Discussion: As the baby boom generation approaches retirement age, the continuing obesity epidemic signals a likely expansion in the population with obesity‐related comorbidities. A framework to combine BMI and demographic trends is essential in evaluating the burden and disparity associated with the epidemic in the aging U.S. population.  相似文献   

11.
The Pacific walrus population has been depleted and subsequently allowed to recover three times in the past 150 yr. As we see it, the population has been made to fluctuate like an r-selected species, rather than being maintained at a high, stable level, as befits a K-selected species. The latest depletion began in the 1930s but was not recognized until 25 yr later, by which time the population had been reduced by at least half. Without benefit of communication, the U.S.S.R. and the State of Alaska put similar protective measures into place by 1960, and in the next two decades the walrus population recovered again, at least doubling in size. By 1980, it already was showing density-dependent signs of having approached or reached the carrying capacity of its environment. As productivity and calf survival declined sharply in the late 1970s and early 1980s the catches more than doubled. We believe that the combined effects of natural curtailment and human intervention may be bringing the population down again rather rapidly. With the present, crude monitoring methods, delayed management responses, and poor international communications, however, the downward trend may not be acknowledged for at least another decade, by which time the unilateral Soviet and American corrective measures are likely to be too much, too late. Walrus management needs to be based less on response to immediate crisis and more on long term prediction than it has been in the past. Because the U.S.A. and U.S.S.R. are trying to manage the same walrus population, without sufficient communication or consensus and sometimes to opposite ends, an international joint management program needs to be implemented.  相似文献   

12.
Survival rates and life expectancies are commonly agreed upon indicators of well‐being for animals in zoological facilities, but even the most recent survival statistics for bottlenose dolphins (Tursiops truncatus) in marine mammal parks and aquariums use data that are now more than 25 yr old. The current study provides a comprehensive assessment of life expectancy and survival rates for bottlenose dolphins in U.S. zoological facilities from 1974 to 2012, utilizing three different analyses (annual survival rate, age‐at‐death, and Kaplan‐Meier), examining historical trends, and comparing to comparable data from wild populations. Both survival rate and life expectancy for dolphins in zoological facilities increased significantly over the past few decades, with a modern ASR of 0.972, and mean and median life expectancies calculated via Kaplan‐Meier of 28.2 and 29.2 yr, respectively. Survival rates and life expectancies for dolphins in U.S. zoological facilities today are at least as high as those for the wild dolphin populations for which there are comparable data.  相似文献   

13.
In her digital photomontage Working Woman (1997), U.S.-based Nigerian artist Fatimah Tuggar stages a disjunctive encounter between the aesthetic procedures of the historical avant-garde and a postcolonial feminist critique of the visual imagery of the “Afro-optimism” that became prominent in the late 1990s. Treating the “modern African woman” as a mediatic phantom rather than a taken-for-granted subject-position, Tuggar's work evokes the universal “right to communicate” increasingly claimed by anti-neo-liberal activists in the Global South over the past decade.  相似文献   

14.
Objective: To evaluate the association between birthplace (Mexico or U.S.) and obesity in men and women and to analyze the relationship between duration of U.S. residency and prevalence of obesity in Mexican immigrants. Research Methods and Procedures: We used cross‐sectional data from 7503 adults of Mexican descent residing in Harris County, TX, to evaluate the relationships among BMI, birthplace, and years of residency in the U.S., controlling for demographic characteristics, physical activity level, and acculturation level. Results: U.S.‐born adults had an increased risk (between 34% and 65%) of obesity compared with their Mexican‐born counterparts. After controlling for recognized confounders and risk factors, this association was maintained in the highly acculturated only. Among highly acculturated obese U.S.‐born men, 6% of the cases were attributable to the joint effect of birthplace and acculturation; in women, this proportion was 25%. Among Mexican‐born women, there was an increasing trend in mean BMI with increasing duration of residency in the U.S. Compared with immigrants who had lived in the U.S. for <5 years, Mexican‐born women who had resided in the U.S. for ≥15 years had an adjusted BMI mean difference of 2.12 kg/m2 (95% confidence interval, 1.53–2.72). Discussion: Mexican‐born men and women have a lower risk of obesity than their U.S.‐born counterparts, but length of U.S. residency among immigrants, especially in women, is directly associated with risk of obesity. Development of culturally specific interventions to prevent obesity in recent immigrants may have an important public health effect in this population.  相似文献   

15.
D. Ross Robertson 《Oecologia》1995,103(2):180-190
Stegastes diencaeus and S. dorsopunicans are mutually territorial Caribbean damselfishes. S. diencaeus is larger, grows faster and lives longer than S. dorsopunicans. S. diencaeus is a habitat specialist that shares its primary habitat mainly with S. dorsopunicans. Field manipulations show that both S. diencaeus and S. dorsopunicans readily take over living space from smaller, but not larger, heterospecific neighbors. Natural changes in the use of living space by both species occur frequently and adult S. diencaeus often aggressively usurp the living areas of smaller S. dorsopunicans. Lunar and seasonal patterns of juvenile recruitment by S. diencaeus and S. dorsopunicans are similar. Large size bestows competitive superiority on S. diencaeus by giving its adults a superior ability to aggressively acquire living space, and by enabling its juveniles to quickly escape the period when they lack a size advantage. Hence they spend much of their lives as competitive dominants. There is no evidence that competitive advantages arising from large size are offset either by other adult attributes or by differences in temporal patterns of recruitment that affect priority of access to space. The lottery hypothesis for species coexistence relies on patterns of abundance being determined by patterns of recruitment to vacant space because different species have equal space-holding abilities. These data show that the existence of such a mechanism is doubtful.  相似文献   

16.
The anadromous Atlantic sturgeon Acipenser oxyrinchus oxyrinchus, a wide-ranging species along the Atlantic Coast of North America, is being considered for federal listing under the U.S. Endangered Species Act. Identification of distinct population segments (DPS) is necessary but problematic for highly vagile species such as Atlantic sturgeon which may spend a high proportion of their lives outside of their natal estuaries. Characterization of genetic differentiation and estimates of gene flow provide a quantitative measure of the number of DPS into which species could be divided over their distribution and the reproductive independence of each unit. We sequenced a portion of the mitochondrial DNA control region to characterize population structure and gene flow across all naturally reproducing populations from which specimens could be obtained. We then considered these genetic data along with ancillary information on life history characteristics, historical fisheries data, and trajectories of abundance to determine the number of DPS into which this species should be divided. Our results suggest that philopatry is high for Atlantic sturgeon and that each U.S. estuary analyzed hosts genetically distinct populations of Atlantic sturgeon. We conclude that at least nine DPS of Atlantic sturgeon exist along the Atlantic Coast of the U.S. In contrast, the Atlantic Sturgeon Status Review Team has proposed a five DPS scheme for this subspecies based largely on results from nuclear DNA microsatellites, but with fewer populations represented and lower samples sizes. These different conclusions illustrate the somewhat arbitrary nature of the DPS concept, at least as applied to Atlantic sturgeon.  相似文献   

17.
Soybean rust (Phakopsora pachyrhizi) has recently invaded North America and has the potential to be the most destructive foliar disease of soybean. As part of the response to this threat, the Integrated Aerobiology Modeling System (IAMS) was constructed to forecast the aerial movement of this pathogen from subtropical to middle latitude portions of the continent. IAMS simulations have been conducted daily for the past two growing seasons and integrated with information from a nationwide observation network into a decision support system for soybean farmers. After the 2005 season, the United States Department of Agriculture reported that many millions of United States (U.S.) soybean hectares that would have been treated for soybean rust in 2005 were not due to this decision support system. In 2006, soybean rust appeared for the first time in the major U.S. soybean production region over 1000 km from known areas of inoculum production. IAMS predictions of the geographical extent and timing of disease symptom expression were well matched with subsequent observations of the disease in the field.  相似文献   

18.
The pathway and frequency of species' introductions can affect the extent, impact, and management of biological invasions. Here, we examine the pathway of introduction of the aquatic plant Cabomba caroliniana (fanwort) into Canada and the northern United States using plastid DNA sequence (intergenic spacers atpFatpH, trnHpsbA, and trnLtrnF) and DNA content analyses. We test the hypothesis that the spread of fanwort is a result of commercial trade by comparing a Canadian population (Kasshabog Lake, ON) to native populations from southern U.S., introduced populations in northern U.S., and plants from commercial retailers. Thirteen plastid haplotypes were identified throughout North America, including one dominant haplotype, which was present in all C. caroliniana populations. Several rare haplotypes were used to infer shared colonization history. In particular, the Canadian population shared two rare alleles with a population from Massachusetts, suggesting range expansion of C. caroliniana from the northern U.S. However, the possibility of a commercial introduction cannot be excluded, as common alleles were shared between the Canadian population and both commercial and southern U.S. sources. Variation in C. caroliniana genome size was bimodal and populations were classified into “high” and “low” categories. The Canadian population had DNA contents similar to several northern U.S. populations (low DNA content). This may provide additional support for range expansion from these introduced populations rather than from commercial sources or populations in the southern U.S., which had high DNA content.  相似文献   

19.
Objective: To study the secular trends in the disparity of obesity across socioeconomic status (SES) groups among U.S. adults. Research Methods and Procedures: We used national representative data collected in the National Health and Nutrition Examination Surveys conducted in 1971 to 1974, 1976 to 1980, 1988 to 1994, and 1999 to 2000 from 28, 543 adults 20 to 60 years old. Obesity was defined based on BMI calculated using measured weight and height. Trends in the relationship between obesity and education levels were analyzed controlling for age, gender, and ethnicity. Results: The disparity in obesity across SES (less than high school, high school, and college or above to indicate low, medium, and high SES, respectively) has decreased over the past 3 decades. In National Health and Nutrition Examination Surveys I (1971 to 1974), there was as much as a 50% relative difference in the obesity prevalence across the three groups, but by 1999 to 2000, it decreased to 14%. This trend was more pronounced in women. The trends of diminishing disparities in obesity were also revealed by our logistic and linear regression analyses. The odds ratio converged to 1 from the 1970s to 2000. In most sociodemographic groups, the relationship between BMI and SES (coefficients) has been weakened over time. Discussion: The association between SES and obesity has been weakened over the past 3 decades, when the prevalence of obesity increased dramatically. There are considerable variations in the changes in the associations across gender and ethnic groups. Our findings suggest that individual characteristics are not likely the main cause of the current obesity epidemic in the U.S., whereas social‐environmental factors play an important role. Strategies for obesity prevention and management should target all SES groups from a societal perspective.  相似文献   

20.
Codling moth is a notorious fruit-boring pest that has been neglected as a target for biological control introductions. Nonetheless, it is a suitable target as it is an exotic species in the western U.S., on an exotic crop plant, in a relatively undisturbed environment, and has a lower level of abundance in its region of origin in Central Asia. In contrast, it belongs to the Olethreutidae, a family of pests with a very poor history of past successes in the biological control record. From an analysis of a stage-structured model for codling moth, the second instar and cocoon are identified as the most vulnerable life stages in terms of the potential for additional parasitism-based mortality to reduce the intrinsic rate of increase of codling moth populations. Criteria used in the selection of effective parasitoids for introduction to the western U.S. from Central Asia were the absence of antagonistic interactions between parasitoid species, greater than 30% parasitism observed in the region or origin, and parasitoids targeting the second instar and cocoon stages. Three species selected for introduction were the larval parasitoid Bassus rufipes, and two cocoon parasitoids Liotryphon caudatus and Mastrus ridibundus. Of these, M. ridibundus also exhibits three attributes considered to be of value from a theoretical perspective, a positive response to patches of higher host density, a shorter generation time, and production of a greater number of female offspring per host attacked.  相似文献   

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