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A series of four transect or strip censuses of primates was carried out in a forest in eastern Colombia where the absolute density of the three diurnal species had been previously calculated during long-term studies. The diurnal species were Alouatta seniculus, Callicebus torquatus,and Cebus apella.Techniques were identical, except for a few variables tested for their effect on the experimental results;these included three different types of detection distances. Variable results were obtained for the two species having the smallest home ranges (A. seniculusand C. torquatus)with the most consistently accurate densities being calculated using the drop in the frequency distribution of sighting distances as a measure of the detection distance. Grossly inflated results were obtained for almost all calculations of C. apelladensity. The stimulus leading to the detection of particular primate groups was usually their vocalizations. Counts of recognized group members were inaccurate and short of the actual number of individuals in each group. Problems of censusing primates are discussed and some recommendations are made with respect to the use of the transect census method.  相似文献   

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BackgroundThere is evidence of the occurrence of trachoma in Peru, and studies have shown that soil-transmitted helminthiases (STH) are affecting rural communities in the Amazon basin in Loreto Department. This study was done to estimate trachoma prevalence, STH prevalence, and the associated factors for both diseases in children aged 1–9 years in rural communities of Peru.MethodologyA population-based cross-sectional survey was carried out in rural communities of Loreto. A standardized survey questionnaire with individual and household risk factors related to both diseases was used. Ocular examination was done for all participants aged one year and above, and eye swab samples were collected from children with follicular trachoma (TF). Anthropometric measurements, stool samples for STH, and blood samples for hemoglobin measurement were taken from children.Principal findingsTF prevalence was 7.74% (95% CI 5.08–11.63%), STH prevalence was 49.49% (95% CI 25.00–52.43%), and prevalence of co-occurrence of both diseases was 5.06% (95% CI 2.80–8.98%) in children aged 1–9 years. Being at age 3–8 years old (AOR = 6.76; 95% CI 1.346–33.947), have an unclean face (AOR = 24.64; 95% CI 6.787–89.444), and having been dewormed in the last six months (AOR = 2.47; 95% CI 1.106–5.514), were risk factors of TF. Being a female (AOR = 0.22; 95% CI 0.103–0.457) was associated with decreased odds of TF. Having been dewormed in the last six months (AOR = 0.30; 95% CI 0.139–0.628) was a preventative factor for STH. Risk factors for children with both diseases mirrored the findings for risk factors for individual diseases.ConclusionsNeglected tropical diseases and associated risk factors overlap in communities living in vulnerable conditions in the Amazon basin of Peru. These findings support the need to implement integrated interventions, including mass drug administration, water, sanitation, and hygiene for both diseases in the study area.  相似文献   

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It is difficult to make valid comparisons of chimpanzee densities among sites because observers calculate them using different methods. We argue that nest count estimates of density are preferable to densities from home range estimates because of the problems of defining home range. There are many problems associated with nest count methods, some of which have not been addressed in previous studies. In 1992, we censused chimpanzees in the Budongo Forest using three methods;the standing crop nest count (SCNC), the marked nest count (MNC), and visual sightings of the animals (VS). Each method is based on standard line transect techniques. Of 96 nests monitored for decay rate,those constructed in the dry seasons decayed faster than those in the wet seasons. All- day follows of individual chimpanzees and observations of nesting chimpanzees at dusk showed that about 15.8% of night nests were reused,17.5% of the population did not build nests, and 18.8% of nests were first constructed as day nests. Given the variability in nest decay rates, we argue that MNC is a better method than SCNC because it avoids having to calculate decay rates.  相似文献   

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In the decade since the first draft of the human genome was announced, genome sequencing projects have been initiated for an additional twenty-some primate species. Within the next several years, genome sequence data will likely become available for all primate genera and for most individuals within some primate populations. At the same time, gene mapping and association studies of humans and other organisms are rapidly advancing our understanding of the genetic bases of behavioral and morphological traits. Primatologists are especially well-placed to take advantage of this coming flood of genetic data. Here we discuss what this new era of primate genomics means for field primatology and highlight some of the unprecedented opportunities it will afford, particularly with regard to examining the genetic basis of primate adaptation and diversity.  相似文献   

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Based on specimens collected from bats of different families, we add new species and extend the known ecological distribution and host associations of insect ectoparasites of bats in Peru. New information is provided for the distribution of 26 species of parasites (25 Diptera and 1 Siphonaptera: Ischnopsyllidae). Four species (Neotrichobius ectophyllae, Strebla galindoi, Strebla paramirabilis and Myodopsylla wolffsohni wolffsohni) are new for Peru and 16 represent new records for the department of Loreto. Also, we found 17 new host-ectoparasite relationships. Of note, we found remarkable new association between Neotrichobius delicatus and bat species from the families Molossidae and Noctilionidae and a novel association between Paradyschiria parvula and a species of Vespertilionidae. Host-ectoparasite specificity was recorded with 14 species as monoxenous, three oligoxenous, seven pleioxenous and two polyxenous.  相似文献   

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Little is known about patterns and correlates of variation in microgametophyte populations for naturally pollinated plants, yet this information is critical for evaluating the prevalence and potential evolutionary significance of gametophyte competition in the wild. This paper analyzes spatial and temporal variation in microgametophyte populations (= number of pollen tubes per style) for the winter-flowering, perennial herb Helleborus foetidus (Ranunculaceae), based on data from 29 populations in three regions of the Iberian Peninsula collected over two consecutive years. Mean size of microgametophyte populations varied significantly at a wide range of spatial scales, including among regions, among populations within regions, among individual plants within populations, among flowers of the same plant, and among pistils of the same flower (H. foetidus flowers are apocarpous). Differences between regions were quantitatively negligible. Differences between populations in the same region were moderate to low, and their sign and magnitude were inconsistent between years. Roughly half of total variance in microgametophyte numbers was accounted for by variation within individual plants, and the largest part of this component was due to differences between the pistils of the same flower. These results reveal extreme spatial fine-graininess and marked stochasticity in the spatial variation of H. foetidus microgametophyte populations and suggest that opportunities for consistent selection on male gametophyte competitive ability are probably negligible in this species.  相似文献   

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浙闽五个红豆树自然保留种群的遗传多样性   总被引:1,自引:0,他引:1  
红豆树是我国三级保护的珍稀濒危植物,是家具、装饰、雕刻等上等用材。应用ISSR分子标记研究浙闽2省5个红豆树自然保留种群的遗传多样性和种群遗传分化。结果表明,红豆树遗传多样性丰富,物种水平的多态位点百分率高达91.46%,总的种群基因多样性为0.3981,显著地高于其他珍稀濒危树种。研究的5个红豆树自然保留种群虽较小,但皆维持较高水平的遗传多样性,种群多态百分率(PPL)、Nei基因多样性(HE)和Shannon信息多样性指数(I)分别为81.71%~89.02%、0.3498—0.3831和0.5026~0.5506。因现有红豆树种群皆是在过渡采伐后保留下来的,片断化时间较短,种群间遗传分化较小,仅有6.45%的遗传变异存在于自然保留种群间,而种群内的变异占总变异的93.55%。较大的红豆树种群遗传多样性相对较高,应优先加强遗传保育。  相似文献   

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Systematic Parasitology - Among Siluriformes, fishes of the family Doradidae harbor dactylogyrids from Cosmetocleithrum Kritsky, Thatcher and Boeger, 1986. Anadoras grypus (Cope) (Siluriformes,...  相似文献   

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While much can be learned about primates by means of observation, the slow life history of many primates means that even decades of dedicated effort cannot illuminate long-term evolutionary processes. For example, while the size of a contemporary population can be estimated from field censuses, it is often desirable to know whether a population has been constant or changing in size over a time frame of hundreds or thousands of years. Even the nature of “a population” is open to question, and the extent to which individuals successfully disperse among defined populations is also difficult to estimate by using observational methods alone. Researchers have thus turned to genetic methods to examine the size, structure, and evolutionary histories of primate populations. Many results have been gained by study of sequence variation of maternally inherited mitochondrial DNA, but in recent years researchers have been increasingly focusing on analysis of short, highly variable microsatellite segments in the autosomal genome for a high-resolution view of evolutionary processes involving both sexes. In this review we describe some of the insights thus gained, and discuss the likely impact on this field of new technologies such as high-throughput DNA sequencing.  相似文献   

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The Platte River caddisfly (Ironoquia plattensis Alexander and Whiles 2000) was recently described from a warm-water slough along the Platte River in central Nebraska and was considered abundant at the type locality. Surveys of 48 sites in 1999 and 2004 found eight additional sites with this species on the Platte River. The caddisfly was not found at the type locality in 2004 and one additional site in 2007, presumably because of drought conditions. Because of its apparent rarity and decline, the Platte River caddisfly is a Tier I species in Nebraska. For this project, surveys for the caddisfly were conducted at 113 new and original sites primarily along the Platte, Loup, and Elkhorn Rivers between 2009 and 2011. These surveys identified 30 new sites with the caddisfly. Larval densities were quantified at a subset of inhabited sites, and there was a large variation of densities observed. Seven sites on other Nebraska drainages were found to support morphologically similar caddisflies, presumably the Platte River caddisfly. Because of the discovery of populations outside the Platte River drainage, amplified fragment length polymorphism (AFLP) was used to determine the amount of genetic variability and breeding among sites on the Platte, Loup, and Elkhorn Rivers. Analysis of molecular variance (AMOVA) suggested moderate gene flow among the three river systems and that there was more genetic variation within populations than between populations. Differentiation, but not total divergence, was exhibited by the northernmost population from the Elkhorn River. Because it may be considered an indicator species and is vulnerable to ongoing habitat loss and degradation, all Platte River caddisfly populations should be conserved.  相似文献   

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A transect census technique was used to estimate the population densities of Saguinus mystax and Saguinus fuscicollis at two sites in Peru. Cropping of these two species had occurred five years before the census at one site and two years before at the other. The populations of S. mystax at both sites had recovered completely from cropping, and the relationship between S. mystax and S. fuscicollis had not been altered at one site and had been reversed in favor of S. mystax at the other.  相似文献   

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In a stochastic environment, long-term fitness can be influenced by variation, covariation, and serial correlation in vital rates (survival and fertility). Yet no study of an animal population has parsed the contributions of these three aspects of variability to long-term fitness. We do so using a unique database that includes complete life-history information for wild-living individuals of seven primate species that have been the subjects of long-term (22-45 years) behavioral studies. Overall, the estimated levels of vital rate variation had only minor effects on long-term fitness, and the effects of vital rate covariation and serial correlation were even weaker. To explore why, we compared estimated variances of adult survival in primates with values for other vertebrates in the literature and found that adult survival is significantly less variable in primates than it is in the other vertebrates. Finally, we tested the prediction that adult survival, because it more strongly influences fitness in a constant environment, will be less variable than newborn survival, and we found only mixed support for the prediction. Our results suggest that wild primates may be buffered against detrimental fitness effects of environmental stochasticity by their highly developed cognitive abilities, social networks, and broad, flexible diets.  相似文献   

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Fungi are among the most important aeroallergens. The aim of this study was to provide aeromycological baseline information about Zarqa area, Jordan, for the first time. During the entire survey and from 170 settle plate exposures, a total of 735 mould- and 274 yeast colony-forming units (CFU) were collected. mould colonies were assigned to 35 genera and 59 species. The highest abundance was attributed to Cladosporium with a percentage of 29.1% of the total colony count followed by Fusarium 20%, Alternaria 7.7%, Ulocladium 6.5% Penicillium 4.2% and then Aspergillus 3.6%. Cladosporium showed one peak in October while Aspergillus and Penicillium peaked in September. Fusarium peaked in May and August and Alternaria in March and July. However, Ulocladium showed almost the same abundance from March to June and then in September and December. A double peak in total colony count and fungal diversity was found, the first was in March and the second in November–December. Significant differences of total fungal colony counts favouring the 1500 hours collection time over that at 1000 hours were found between November and January while no such significant differences were obtained between February and April. Our results also indicated differences in species composition between the two periods in different months. Spores of the three abundant species, Cladosporium, Fusarium and Alternaria, might favour high release in the 1500 hours period during winter while having a similar incidence during the two periods in the spring months.  相似文献   

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To understand whether or not primate populations recover in areas of abandoned human settlements, data are required that allow for site‐specific comparison over time. Here, we present baseline information on the presence/absence and relative abundance of primate species at the abandoned settlement of the Ekundukundu village, relocated out of the Korup National Park in 2000. Between July 2007 and March 2008, 62 km of transects was surveyed for sightings and calls of primates. All eight species of diurnal primates reported in the KNP were confirmed: Cercopithecus nictitans ludio, C. mona, C. erythrotis camerunensis, C. pogonias, Procolobus pennantii preussi, Cercocebus torquatus, Mandrillus leucophaeus leucophaeus, and Pan troglodytes vellerosus. At old Ekundukundu, C. nictitans accounted for 65% of all primate group sightings. Overall, sighting frequency of primates (0.55 groups/km) was not significantly different from other park sectors surveyed by a previous observer (J. Linder) in 2004–2005. The data reported here will be useful in the long‐term monitoring of primate populations in regenerating forest habitats of earlier human settlements. Am. J. Primatol. 72:645–652, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   

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