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1.
Butterfly species richness in mainland Portugal: predictive models of geographic distribution patterns 总被引:6,自引:0,他引:6
A three-step protocol described elsewhere is used to obtain a map of butterfly species density in Portugal on a 50×50 km grid. First, all available faunistic information was compiled and analysed to explore the historic patterns of butterfly sampling in Portugal, and to determine which grid cells are sufficiently prospected to produce reliable estimates of species richness. Then, we relate the estimated species richness scores from these areas to a set of environmental and spatial variables by means of General Linear Models, obtaining a function to extrapolate of species density scores to the rest of Portugal. Finally, the model is validated, results explored and outliers identified and deleted. Any spatial autocorrelation remaining in the residuals is examined. Lastly, model parameters are recalculated in absence of deleted outliers, and the resulting function is used to predict species richness scores throughout mainland Portugal. A highly-predictive function based on some variables previously related to butterfly composition at macro-scale, such as number of sunny days per year, temperature or environmental heterogeneity, was obtained. However, in Portugal those variables are highly spatially structured along a steep latitudinal gradient, leading to difficulty in ascertaining if the latitudinal gradient detected by our analysis is due to macroecological or historic effects. Information on European and Iberian butterfly assemblages and causal processes are discussed in the light of the patterns observed. Then, previous information obtained on Portuguese scarabs is added to identify conservation areas, biogeographically important for both insect groups. Finally, the main drawbacks and advantages of this approach to mapping biodiversity for conservation are discussed briefly. 相似文献
2.
Birol G Wang S Budzynski E Wangsa-Wirawan ND Linsenmeier RA 《American journal of physiology. Heart and circulatory physiology》2007,293(3):H1696-H1704
The oxygen distribution in the retina of six anesthetized macaques was investigated as a model for retinal oxygenation in the human retina in and adjacent to the fovea. P(O2) was measured as a function of retinal depth under normal physiological conditions in light and dark adaptation with O(2) microelectrodes. Oxygen consumption (Q(O2)) of the photoreceptors was extracted by fitting a steady-state diffusion model to P(O2) measurements. In the perifovea, the P(O2) was 48 +/- 13 mmHg (mean and SD) at the choroid and fell to a minimum of 3.8 +/- 1.9 mmHg around the photoreceptor inner segments in dark adaptation, rising again toward the inner retina. The P(O2) in the inner half of the retina in darkness was 17.9 +/- 7.8 mmHg. When averaged over the outer retina, photoreceptor Q(O2) (called Q(av)) was 4.6 +/- 2.3 ml O(2).100 g(-1).min(-1) under dark-adapted conditions. Illumination sufficient to saturate the rods reduced Q(av) to 72 +/- 11% of the dark-adapted value. Both perifoveal and foveal photoreceptors received most of their O(2) from the choroidal circulation. While foveal photoreceptors have more mitochondria, the Q(O2) of photoreceptors in the fovea was 68% of that in the perifovea. Oxygenation in macaque retina was similar to that previously found in cats and other mammals, reinforcing the relevance of nonprimate animal models for the study of retinal oxygenation, but there was a smaller reduction in Q(O2) with light than observed in cats, which may have implications for understanding the influence of light under some clinical conditions. 相似文献
3.
Caroline Ross 《Primates; journal of primatology》1992,33(2):207-215
Macaques are found both in broadleaf evergreen forest and in more variable habitats. The former group might be expected to be subject to less variability in their environment and hence to suffer lower rates of density independent mortality. Life history evolution models predict that species in such conditions will have lower rates of development and breeding than those found in more variable habitats where density independent mortality is high. This prediction is tested here by comparing the breeding and development rates of nine species of macaque. Although measures of developmental rate are not found to vary in a predictable way with habitat, measures of breeding rate do correlate with habitat categories used. As predicted, species that are found in more variable habitats tend to have higher birth rates and a higher intrinsic rate of natural increase than do species in more stable, forest habitats. Contrary to prediction selection does not always act to produce an early age at first reproduction in macaques living in seasonal environments. This is discussed with relation to physiological and environmental constraints. 相似文献
4.
Bailey MT Coe CL 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2002,133(2):379-388
The intestinal microflora of common marmosets and rhesus monkeys were compared by enumerating bacteria from the small and large intestines. Rhesus monkeys had a consistent microflora pattern manifest by higher concentrations of total and Gram-negative aerobic and facultatively anaerobic bacteria, as well as aerobic and anaerobic Lactobacilli, in the large intestine as compared to the small intestine. In contrast, the marmoset microflora were considerably more variable. Approximately two-thirds of the marmosets (designated group A) had an overall profile that resembled the rhesus monkeys, but they had significantly higher concentrations of Gram-negative microflora in their large intestines than the rhesus monkeys. The remaining marmosets (group B) had higher concentrations of bacteria in the small intestine as compared to the large intestine, with the large intestinal concentrations being significantly lower than in the rhesus monkeys and group A marmosets. Moreover, the marmosets did not have detectable levels of aerobic Lactobacilli, and anaerobic Lactobacilli concentrations were significantly lower than in the rhesus macaques. Although it is unknown why microflora differ across species, it is likely that evolutionary adaptations in anatomy and functioning of the gastrointestinal tract influence the concentration and types of bacteria residing as the normal intestinal microflora. 相似文献
5.
6.
'Latitude' and geographic patterns in species richness 总被引:8,自引:0,他引:8
Bradford A. Hawkins 《Ecography》2004,27(2):268-272
7.
Masao Kimura 《Animal genetics》1978,9(1):13-20
Electrophoretic variations of enzymatic and non-enzymatic proteins were investigated in 8 populations of the loach Misgurnus anguillicaudatus . The cathodic hemoglobin and the muscle protein in the region II were shown to be polymorphic, in addition to the five polymorphic proteins previously reported (the anodic hemoglobin, muscle protein in the region III, 6-phosphogluconate dehydrogenase, phosphoglucomutase and aspartate aminotransferase; Kimura, 1976 & 1977). The muscle proteins in the regions I, IV and V were monomorphic. The values of genetic distances between loach populations, calculated over 10 loci, indicated that M. anguillicaudatus should be classified into two local races. 相似文献
8.
M Kimura 《Animal blood groups and biochemical genetics》1978,9(1):13-20
Electrophoretic variations of enzymatic and non-enzymatic proteins were investigated in 8 populations of the loach Misgurnus anguillicaudatus. The cathodic hemoglobin and the muscle protein in the region II were shown to be polymorphic, in addition to the five polymorphic proteins previously reported (the anodic hemoglobin, muscle protein in the region III, 6-phosphogluconate dehydrogenase, phosphoglucomutase and aspartate aminotransferase; Kimura, 1976 & 1977). The muscle proteins in the regions I, IV and V were monomorphic. The values of genetic distances between loach populations, calculated over 10 loci, indicated that M anguillicaudatus should be classified into two local races. 相似文献
9.
Broad-scale geographic patterns in the distribution of vertically-transmitted, asexual endophytes in four naturally-occurring grasses in Sweden 总被引:1,自引:0,他引:1
Dawn R. Bazely John P. Ball Mark Vicari rew J. Tanentzap Myrtille Bérenger Tomo Rakocevic Saewan Koh 《Ecography》2007,30(3):367-374
The presence and distribution of vertically-transmitted, asexual Neotyphodium/Epichloë endophytes in four species of widely distributed grasses, all members of the sub-family Pooideae, were determined at 57 spatially-distinct sites across Sweden in naturally-occurring grass populations. While these endophytes are well-studied in agricultural systems, much less is known about their abundance and distribution in non-agricultural systems at larger scales across landscapes. We used two screening methods to detect endophytes: 1) visual inspection of fixed, stained grass shoots, and 2) immunoblot cards with monoclonal antibodies specific for Neotyphodium / Epichloë endophytes. Infection frequency (i.e. the proportion of individuals) varied widely among species and among sites, a finding common to most studies performed in non-agricultural ecosystems. Festuca rubra had the highest overall infection frequency (23% visual screening, 27% immunoblot screening), while Deschampsia flexuosa (4%) and Poa trivialis (4%) had low frequencies of infection. None of the sampled Agrostis capillaris populations were infected. In F. rubra , the within-site infection frequency varied from 0 to 100%. A significant altitudinal gradient was found for F. rubra , with the infection frequency of the vertically-transmitted endophyte Epichloë festucae decreasing with increasing altitude above sea level. The high variation across and within grass species at different geographical locations that ours and others' studies reveal, agree with suggestions that agronomic model systems cannot be readily extrapolated to understand the ecological role of endophytes in native grasses in the wild. Further investigation into the underlying cause of the observed altitudinal gradient is required to understand broader-scale patterns in the distribution of endophyte-infected grasses. 相似文献
10.
Song JY Kitamura S Jung SJ Miyadai T Tanaka S Fukuda Y Kim SR Oh MJ 《Journal of microbiology (Seoul, Korea)》2008,46(1):29-33
Viruses belonging to the genus Megalocytivirus in the family Iridoviridae have caused mass mortalities in marine and freshwater fish in Asian countries. In this study, partial major capsid protein (MCP) gene of seven Japanese and six Korean megalocytiviruses was sequenced and compared with the known megalocytiviruses to evaluate genetic variation and geographic distribution of the viruses. Comparison of MCP gene nucleotide sequences revealed sequence identity of 92.8% or greater among these 48 isolates. A phylogenetic tree clearly revealed three clusters: genotype I including nine Japanese isolates, thirteen Korean isolates, one Chinese isolates, one Thailand isolate and one South China Sea isolate; genotype II including five freshwater fish isolates in Southeast Asian countries and Australia; and the remaining genotype III mainly consisted of flatfish isolate in Korea and China. This suggests that viruses belonging to the genotype I widely distribute among various fish species in many Asian countries. Conversely, the epidemic viruses belonged to genotype II and III are may be still locally spreading and constrained in their prevalence to the limited host fish species, i.e., genotype II viruses mainly distribute in Southeast Asian countries, whereas genotype III viruses distribute in flatfish species in Korea and China. 相似文献
11.
All members of the Herpesviridae family contain sequences for a highly conserved glycoprotein B (gB) gene. We investigated the phylogenetic relationships of gB sequences from eight independent rhadinovirus isolates obtained from three species: rhesus (Macaca mulatta), cynomologus (Macaca fasicularis), and pig-tailed (Macaca nemestrina) macaques. Samples were derived from monkeys housed at four separate facilities. Analysis of these eight independent gB sequences revealed five regions of heterogeneity within the 823- to 829-amino-acid polypeptides: residues 1 to 65, 120 to 185, 255 to 300, 352 to 393, and 412 to 457. The remaining regions of gB were highly conserved among the different macaque isolates. Overall divergence among these gene sequences ranged from 0.1 to 7.2% at the amino acid level. Phylogenetic trees constructed with our macaque rhadinovirus gB sequences and those derived from additional subfamilies or genera (alpha, beta, gamma-1, and gamma-2) revealed that the macaque gB sequences branched with other gamma-2 herpesvirus gB sequences and that within the gamma-2 genera, the macaque gB sequences clustered as a distinct branch. The eight macaque rhadinovirus gB sequences were all approximately equidistant from Kaposi sarcoma-associated herpesvirus (KSHV) gB sequences and had a shorter evolutionary distance to KSHV gB sequences than to any other herpesvirus, including the gamma-2 herpesvirus saimiri (HVS) of New World squirrel monkeys. The macaque gB sequences did not cluster according to the facility of origin, but did cluster according to the species of origin, displaying less intraspecies divergence (0.1 to 2.9%) than interspecies divergence (3.3 to 7.2%). These results demonstrate a close relatedness of rhadinovirus isolates from different macaque species. 相似文献
12.
Martin Unterseher Almut Reiher Knut Finstermeier Peter Otto Wilfried Morawetz 《Mycological Progress》2007,6(3):201-212
In 2005, researchers at the Leipzig Canopy Crane Research Facility collected living leaves of four temperate tree species at heights of between 15 and 33 m above the ground. Following surface sterilisation of the leaves, leaf-fragments were cultured on malt extract agar which allowed the growth of endophytic fungi into the surrounding medium. Isolated cultures were identified by morphology and sequence analysis of the D1/D2 region of the large subunit rDNA. Phylogenetic analysis established the taxonomic positions of the fungi. A total of 49 different taxa were identified, representing 20 families and ten orders. With the exception of one basidiomycetous yeast, all taxa belonged to filamentous ascomycetes. Species richness was highest on Tilia cordata and lowest on Quercus robur. Species-accumulation curves showed that the sampling effort was not sufficient to cover the majority of the likely species at the investigation site. Most endophytes proved to be ubiquitous within the canopy of the investigation site, but habitat preferences in terms of different tree species, different light regimes and season (sampling times) were obvious for some abundant endophytes. Apiognomonia errabunda and Aspergillus niger occurred predominantly on Q. robur, Diplodina acerina on Acer pseudoplatanus, one species of Phoma significantly prefered shaded leaves from the lower canopy layer whereas Sordaria fimicola prefered sun-exposed leaves from the upper tree crowns. Seasonal patterns were observed, for example, for A. errabunda, which was abundant in young leaves in the spring and almost completely absent in aged autumn-leaves, thus suggesting the accumulation of antifungal secondary plant metabolites during the growing season. Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users. Wilfried Morawetz died in March 2007. 相似文献
13.
Two-dimensional electrophoretic analysis of water-soluble proteins of chicken egg yolk was done by a first-dimension separation in agarose gel (pH 8.6) followed by a second-dimension separation in horizontal polyacrylamide gel (pH 9.0). Genetic polymorphism of a protein, tentatively designated as Pr M prealbumin, was observed. The analysis of family data suggests that the Pr M prealbumin is controlled by two alleles, Pr M+ and Pr M-, at a single autosomal locus. The Pr M+ allele appears to be dominant to the Pr M- allele. 相似文献
14.
15.
Thirty-two phenotypes of alpha-1-antitrypsin (al-AT) controlled by 18 codominant alleles of PImac locus were identified by isoelectric focusing in 1.121 macaques of nine species. In terms of al-AT polymorphism macaque species
vary markedly from nearly monomorphic (Macaca mulatta, M. arctoides) to highly polymorphic (M. nemestrina, M. fascicularis). Only 4 of 18 PImac alleles are common for two or more macaque species, the rest of the alleles are species-specific. 相似文献
16.
Interspecific associations can arise for varied reasons including reduced predation risk and improved foraging success. In the case of bird–primate associations, birds typically appear to follow primate groups to harvest insects flushed by primates' movements. However, while previous studies have linked temporal changes in bird–primate associations to environmental conditions, few have assessed the additional effects of bird activity patterns and primate group behaviour and none have disentangled their potentially interdependent effects. Here, we test the hypothesis that foraging opportunities can drive interspecific associations in a previously undescribed bird–primate association between rock kestrels Falco rupicolus and chacma baboons Papio ursinus in central Namibia. Data were collected from two baboon groups and associated kestrels using instantaneous scan sampling during full-day follows over a 7-month field period, and analysed using generalized linear mixed models. We found that kestrel associations with baboons vary with season, show diurnal cycles and are more frequent when the baboons are in open desert habitat, engaged in travel foraging and in a large group. These patterns are statistically independent and consistent with the hypothesis that the kestrel–baboon association is driven by the foraging opportunities acquired by the kestrels. As the baboons do not appear to gain any benefits nor incur any costs from the association, we conclude that the kestrels are likely to be commensal with the baboons. 相似文献
17.
Geographical diversity gradients, even among local communities, can ultimately arise from geographical differences in speciation and extinction rates. We evaluated three models—energy-speciation, energy-abundance, and area—that predict how geographic trends in net diversification rates generate trends in diversity. We sampled 96 litter ant communities from four provinces: Australia, Madagascar, North America, and South America. The energy-speciation hypothesis best predicted ant species richness by accurately predicting the slope of the temperature diversity curve, and accounting for most of the variation in diversity. The communities showed a strong latitudinal gradient in species richness as well as inter-province differences in diversity. The former vanished in the temperature-diversity residuals, suggesting that the latitudinal gradient arises primarily from higher diversification rates in the tropics. However, inter-province differences in diversity persisted in those residuals—South American communities remained more diverse than those in North America and Australia even after the effects of temperature were removed. 相似文献
18.
Understanding how environmental parameters interact to govern species distributions is a shared goal of ecology and biogeography. Biotic and abiotic conditions can change distributions by affecting the nature of interspecific interactions. Although documented in free-living systems, this context dependency has been neglected in parasite interactions. We investigated the influence of condition-specific competition on the specificity of two species of feather lice (Phthiraptera: Ischnocera) that share a host, the mourning dove (Zenaida macroura). We show that relative humidity restricts the range of one species, Columbicola macrourae3 (i.e., the C. macrourae lineage found on mourning doves), to the more humid eastern United States. The second species, Columbicola baculoides, an arid-adapted species, is restricted to drier regions of the western United States by C. macrourae3, which outcompetes it in experiments. Thus, arid conditions in the West provide C. baculoides with a climatic refuge from the competitively superior C. macrourae3, effectively doubling parasite diversity on one host species. These results support the hypothesis that abiotic factors can determine species distributions on the stressful end of an environmental gradient while interspecific competition governs distributions at the benign end. The balance between these factors is subject to change as environmental conditions change, even if the host distribution remains unaffected. 相似文献
19.
Li Y Wang XL Jiao L Jiang Y Li H Jiang SP Lhosumtseiring N Fu SZ Dong CH Zhan Y Yao YJ 《Journal of microbiology (Seoul, Korea)》2011,49(6):913-919
Ophiocordyceps sinensis is one of the best known fungi in Traditional Chinese Medicine. Many efforts have been devoted to locating the production areas of this species resulting in various reports; however, its geographic distribution remains incompletely understood. Distribution of O. sinensis at the county level is clarified in this work based on both a literature search and fieldwork. More than 3600 publications related to O. sinensis were investigated, including scientific papers, books, and online information. Herbarium specimens of O. sinensis and field collections made by this research group during the years 2000-2010 were examined to verify the distribution sites. A total of 203 localities for O. sinensis have been found, of which 106 are considered as confirmed distribution sites, 65 as possible distribution sites, 29 as excluded distribution sites and three as suspicious distribution sites. The results show that O. sinensis is confined to the Tibetan Plateau and its surrounding regions, including Tibet, Gansu, Qinghai, Sichuan, and Yunnan provinces in China and in certain areas of the southern flank of the Himalayas, in the countries of Bhutan, India and Nepal, with 3,000 m as the lowest altitude for the distribution. The fungus is distributed from the southernmost site in Yulong Naxi Autonomous County in northwestern Yunnan Province to the northernmost site in the Qilian Mountains in Qilian County, Qinghai Province, and from the east edge of the Tibetan Plateau in Wudu County, Gansu Province to the westernmost site in Uttarakhand, India. The clarification of the geographic distribution of O. sinensis will lay the foundation for conservation and sustainable use of the species. 相似文献
20.
We studied time budgeting of lion-tailed macaques in the Anamalai Wildlife Sanctuary, Tamil Nadu, India, with regard to seven activity categories. Groups spent >50% of their time feeding and foraging, 33% of the time resting, and 15% moving. More energetic activities were spread uniformly through the day. Feeding had two annual peaks: one closely following the northeast monsoon and the other corresponding to the southwest monsoon. These also coincided with peaks of food availability and mating. Time saved in feeding was spent mostly on resting. Ranging showed a pattern contrary to that of time spent moving and was related more to weather than to food availability; it increased during cooler periods. The middle and upper stories of the canopy were used >93% of the time. The ground was used rarely. Time budgeting characteristics of the lion-tailed macaque are primarily frugiinsectivorous adaptations to a wet evergreen forest habitat. 相似文献