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1.
The carnivorous wetland plant, Sarracenia purpurea (the northern pitcher plant) is native to eastern and Midwestern North America. This species is abundant within its habitat but suitable habitat is increasingly scarce, raising interest in S. purpurea restoration and conservation. Complicating conservation planning, two controversial subspecies of S. purpurea are historically defined primarily on morphologic traits: S. purpurea subsp. purpurea distributed north of Maryland and S. purpurea subsp. venosa distributed south of Maryland. S. purpurea is also found in three distinct habitat types defined by substrate: acidic Sphagnum peatlands, acidic sandy savannahs, and alkaline marl wetlands. In species level studies, S. purpurea leaves have exhibited morphological plasticity in response to environmental variability, bringing into question the validity of subspecies definitions based on morphology alone. This study examined morphologic and genetic variation throughout S. purpurea’s natural distribution, encompassing both the traditional subspecies and three unique habitat types testing the validity of traditional subspecies definitions. Genetic analysis indicated possible ecological significance of considering a new grouping of S. purpurea populations into Midwest, N. East Coast and S. East Coast populations (AMOVA % variation = 13.34, P = 0.0078) based on genetic differentiation. Morphological variation in leaf shape measurements supported this division as well as indicating plasticity associated with environmental variables. This study conservatively suggests that new, geographical area conservation units may be a more important conservation unit for preserving S. purpurea genetic variation and morphological plasticity than traditional subspecies definitions.  相似文献   

2.
There is no long-term study on the white-headed leaf-eating monkey in Hua Shan, Guangxi Zhuang Autonomous Region, China. This subspecies probably numbers ≤400 animals (Wu, 1983; Jiang et al., 1991). Our preliminary study 15 km from the Vietnamese border documents group size and composition and habitat use based on 450 contact h. The study group may interact with the white-sideburned (white-cheeked or black) subspecies of Presbytis francoisi,and shares habitat with macaques. While the study site is contiguous with a provincial park and P. francoisiare under protective legislation, development of this area for tourism and occasional local hunting has consequences for conservation policy.  相似文献   

3.
Accurately predicting the response of species to climate change is crucial for the preservation of contemporary species diversity. In the current study, we analyze the response of two congeneric small mammal species (Peromyscus maniculatus and Peromyscus truei) to recent climate change in the region of Yosemite National Park (California, USA). The generalist P. maniculatus did not change its distribution in response to climate change while the specialist P. truei substantially changed its geographic and elevational distribution in the region, expanding into Yosemite. Using molecular genetic techniques we found that a cryptic geographic shift in genetic variation may have occurred within the geographically stable P. maniculatus distribution. Using a combination of morphometric and molecular genetic techniques we confirmed that a P. truei subspecies previously identified as a habitat specialist expanded into new habitat types, suggesting that this subspecies is not in fact a habitat specialist. Instead, we propose that the range of this subspecies is instead limited by climatic variables currently varying in response to contemporary climate change. These results underscore the importance of verifying the natural‐history‐based assumptions used to develop predictive models of species' response to climate change.  相似文献   

4.
The Common Pheasant Phasianus colchicus is widely distributed in temperate to subtropical regions of the Palaearctic realm. Populations of Common Pheasant have been classified into five subspecies groups based on morphological variations in male plumage. Previous phylogeographical studies have focused on limited sets of subspecies groups in the eastern Palaearctic and knowledge on subspecies in the western Palaearctic region is still poor. In this study, we undertake the first comprehensive analysis of subspecies from all five defined subspecies groups across the entire Palaearctic region. Two mitochondrial (CYTB and CR) and two nuclear (HMG and SPI) loci were used to investigate genetic relationships of these subspecies groups and to infer their dispersal routes. Our results revealed that the subspecies elegans, with its range in northwestern Yunnan, China, was in the basal position among 17 studied subspecies, supporting a previous hypothesis that the Common Pheasant most probably originated in forests in southeastern China. Subspecies in the western Palaearctic region nested within the most subspecies‐rich torquatus group (‘Grey‐rumped Pheasants’), indicating that the torquatus group is not a clade but instead forms a gradation with other subspecies and subspecies groups. Our dating analysis suggested that the initial divergence among populations of Common Pheasant originated around 3.4 Mya with subsequent dispersal into the Western Palaearctic region during the Late Pliocene–Lower Pleistocene approximately 2.5–1.8 Mya. We propose two possible east‐to‐west colonization routes for the Common Pheasant and suggest conservation implications for some regional subspecies. Overall, this study demonstrates the lack of concordance between morphology‐based subspecies delimitation and their genetic relationships. This is likely to be a consequence of initial isolation due to historical vicariance followed by population admixture due to recent range expansion of Common Pheasant in the western Palaearctic region.  相似文献   

5.
Cochemiea pondii subsp. maritima is illustrated, the species and all three subspecies described, each provided with a full synonymy, statements on distribution, habitat and ecology, etymology, phenology, and conservation status. A commentary is given on the re‐acceptance of Cochemiea, separated from Mammillaria. Cultivation notes are provided; the species, and in particular subspecies maritima, is far from common in cultivation and not widely available. The discussion covers aspects of recognition of the subspecies, type collections, related taxa, and comments on the addition of several more species to the genus by Doweld.  相似文献   

6.
7.
Ecological niche models can be useful for clarifying relationships between environmental factors and a species’ geographic distribution. In this study, we use presence‐only data and environmental layers to create an ecological niche model to better understand the distribution of the East African Angolan black and white colobus monkey, Colobus angolensis palliatus, and to assess whether the model supports considering the population as two separate subspecies, Colobus angolensis sharpei and C. a. palliatus. We found the range of the predicted distribution for suitable habitat of C. a. palliatus as currently classified to be only 12.4% of that shown in the International Union for Conservation of Nature Red List range map and to be fragmented. As C. angolensis is considered a “Least Concern” species, this difference suggests that generalized maps may lead to understating the species’ extinction risk. When presence points were divided into two previously proposed subspecies —C. a. palliatus (Kenya and Northern Tanzania) and C. a. sharpei (Southern Tanzania)—we found significant environmental differences between the distributions. The most important ecological variable for C. a. palliatus was predominantly precipitation of the driest month (69.1%) whereas for C. a. sharpei annual precipitation (44.8%) and land cover (normalized difference vegetation index, 16.4%) were the most important. When comparing suitable ranges for the separate distributions, we found only a 1.2% geographical overlap. These differences are consistent with previous subspecies delineations of C. a. palliatus and C. a. sharpei based upon morphology, pelage, and genetics. Our study suggests that extirpation of C. a. palliatus in suitable habitat areas and occurrence of this subspecies in anthropogenic environments, warrant further consideration for conservation actions.  相似文献   

8.
Little is known about genetic variation in the 6–8 subspecies of Colobus angolensis, currently distinguished by pelage differences. We present a comparative genetic analysis of one of these subspecies, C. a. palliatus, in Kenya and Tanzania that assesses evolutionary relationships and patterns of mitochondrial genetic diversity in 103 individuals across its geographic range. Fecal samples from approximately 156 individuals were collected in four localities: (1) Diani Forest, Kenya; (2) Shimoni, Kenya; (3) Udzungwa Mountains National Park, Eastern Arc Mountains, Tanzania; and (4) Mount Rungwe, Southern Highlands, Tanzania. These samples represent at least six groups, with 5–15 samples from each. Comparative sequence analysis of a 1,795 base pair mtDNA fragment revealed 19 unique haplotypes in four populations. Phylogenetic analyses suggest that sampled Kenyan haplotypes are paraphyletic, with one Kenyan haplotype basal to all other sampled haplotypes. Analysis of molecular variance (AMOVA) suggests high levels of genetic variation among populations (ΦST 0.72, P<0.001). Genetic data are concordant with a subspecies level differentiation between C. a. palliatus populations in Kenya and those in Central and southern Tanzania, as earlier suggested based on pelage differences. This study highlights the evolutionary distinctiveness of Kenyan populations of C. a. palliatus relative to Tanzanian populations. Although C. a. palliatus habitat in Tanzania is currently better protected than in Kenya, our results suggest Kenyan and Tanzanian populations should be considered distinct units, and the protection of C. a. palliatus habitat in Kenya, as well as habitat connectivity between Kenyan populations, should be prioritized for conservation and management. Am. J. Primatol. 72:715–724, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   

9.
The geographical differentiation and speciation in the stonechat (Saxicola torquata; Aves: Turdidae) was studied by sequencing a 300-bp fragment of the mitochondrial cytochrome-b gene. Stonechats from three different subspecies inhabiting three continents (S. t. rubicola, the European stonechat; S. t. maura, the Siberian stonechat; and S. t. axillaris, an African stonechat) and stonechats from seven European populations were examined. While variation within the populations of the European subspecies was less than 0.3%, the genetic distances between the subspecies were substantial (2.7-5.7%) in comparison with published data for subspecies of other birds. If speciation is indeed reflected in the cytochrome-b gene of stonechats, species status for the African stonechat, but also for the Siberian taxon, should be reconsidered, especially in the light of differences in distributions, morphology and habitat preference.  相似文献   

10.
One of the major uncertainties of 21st century climate change is the potential for shifts to the intensity and frequency of the El Niño Southern Oscillation (ENSO) cycle. Although this phenomenon is known to have dramatic impacts on ecosystems regionally and globally, the biological consequences of climate change‐driven shifts in future ENSO events have been unexplored. Here, we investigate the potential impacts that a persistent El Niño, La Niña, or ‘Neutral' phase may have on species distributions. Using MaxEnt, we model the distribution of climatically suitable habitat for three northeast Australian butterfly subspecies (Doleschallia bisaltide australis, Hypolimnas alimena lamina, and Mycalesis terminus terminus) across the three ENSO phases. We find that the spatial extent and quality of habitat are lowest under conditions that would characterize a persistent El Niño (hot/dry). In contrast, suitable habitat is broadest under the warm/wet conditions associated with La Niña. Statistical analyses of the difference between pair‐wise combinations of suitability maps using Hellinger distance showed that projections for each subspecies and ENSO phase combination were significantly different from other combinations. The resilience of these, and other, butterfly (sub)species to changes in ENSO will be influenced by fluctuations in the strength of these events, availability of refugia, and life‐history characteristics. However, the population dynamics of wet‐ and dry‐season phenotypes of M. t. terminus and physiological limitations to high temperatures suggest that this subspecies, in particular, may have limited resilience should the strength and frequency of El Niño events increase.  相似文献   

11.
The habitat and discovery of Salvia raymondii is described and the distinctions between the type subspecies and subsp. mairanae are discussed. Subsp. mairanae is illustrated and notes on its cultivation are provided.  相似文献   

12.
The Lahontan cutthroat trout (Oncorhynchus clarkii henshawi) is threatened by habitat destruction, over‐harvest and hybridization with nonnative trout. Currently, three Geographic Management Units (GMUs) are recognized within the taxon. Here, we describe a suite of 68 single‐nucleotide polymorphism (SNP) genetic markers for use in the study and management of Lahontan cutthroat trout and a closely related subspecies, the Paiute cutthroat trout (O. c. seleneris). These include markers variable within the two subspecies (n = 35), diagnostic for the two subspecies (n = 23) and diagnostic for Yellowstone cutthroat trout (O. c. bouvieri) and other closely related subspecies (n = 10). Sixty‐three markers were discovered by Sanger sequencing of 171 EST loci in an ascertainment panel including Lahontan cutthroat trout from four populations representing all GMUs. Five markers were identified in a secondary sequencing effort with a single population of Lahontan cutthroat trout. TaqMan assays were validated on six Lahontan cutthroat trout populations and a diverse panel of other trout. Over 90% of the markers variable in Lahontan cutthroat trout were polymorphic in at least two populations, and 66% were variable within all three GMUs. All Lahontan diagnostic markers were also fixed for the Lahontan allele in Paiute cutthroat trout. Most of the Yellowstone diagnostic markers can also be used for this purpose in other cutthroat trout subspecies. This is the first set of SNP markers to be developed for Lahontan cutthroat trout, and will be an important tool for conservation and management.  相似文献   

13.
Capsule Careful management is required to maintain or create habitats with the correct proportions of rush with reeds that are preferred by this subspecies.

Aims To determine the habitat requirements of Eastern Iberian (Western Iberian Reed Buntings were not included in the study) Reed Buntings Emberiza schoeniclus witherbyi, a subspecies endemic to a few marshes in France, Spain and Morocco, with a population of 254–360 breeding pairs.

Methods Twenty-five wetlands in Spain were surveyed and presence/absence of Iberian Reed Buntings was deteremined together with data on 41 environmental variables. The relationships between the birds and habitat data were investigated using glm.

Results Proportion of rush with reeds, proportion of reed–bulrush patches and perimeter length of rush–reed patches, were the variables that primarily explained the present distribution of Eastern Iberian Reed Buntings. Other vegetation classes traditionally associated with the presence of the Eastern Iberian Reed Buntings, such as sedges, were not found to be important in the selected models.

Conclusion Conservation planning and management guidelines for this subspecies should focus on encouraging these specific-vegetation parameters. Flood control and grazing are proposed as the best practices that will favour these vegetation variables and avoid simplification of the plant community.  相似文献   

14.
李佳  薛亚东  吴波  李迪强 《生态学报》2022,42(18):7484-7494
脆弱性是指物种受气候变化影响的程度,开展脆弱性评估工作有助于人类认识气候变化对野生动物的影响,为制定野生动物适应气候变化的保护对策提供科学依据。采用最大熵模型评估气候变化背景下秦岭地区羚牛(Budorcas taxicolor bedfordi)生境脆弱性。结果表明:(1)当前秦岭地区羚牛适宜生境总面积为6473 km2,到2050s年,预测秦岭地区羚牛适宜生境总面积为4217 km2,减少34.85%,羚牛适宜生境将向更高海拔地区转移,转移约210 m;(2)已建保护区覆盖49.82%当前羚牛适宜生境,尚有3248 km2的适宜生境处于保护区之外;到2050s年,保护区覆盖了43.87%适宜生境,尚有2367 km2的适宜生境未被保护;(3)到2050s年,当前分布在太白县、佛坪县、洋县和宁陕县等地区的3490 km2羚牛适宜生境将会成为生境脆弱区域,丧失53.92%;(4)分布在秦岭核心区域的2983 km2当前和2050s年保持不变适宜生境,将成为羚牛躲避气候变化的庇护所。基于研究结果,就未来羚牛应对气候变化的适应性保护对策提出以下几点建议:考虑将当前羚牛适宜生境纳入国家公园范围、构建适应性生态廊道、加强野生动物监测。  相似文献   

15.
Abstract

Four subspecies of deermice (Peromyscus maniculatus) were selected from habitats along a gradient from mesic hardwood forests (gracilis), tall grass prairie (bairdi), short grass prairie (nebrascensis), to desert grassland (labecula) in effort to relate the light preferences of the mice to the habitat of their origin. Six individuals of each subspecies were maintained in dark chambers for 25 days, during which they could turn on a dim light for 30 seconds on ten of these days. Mice from the mesic habitats turned the lights on more frequently (light reinforcement) than mice from xeric habitats. The same subspecies that exhibited light reinforcement when raised in laboratory light conditions failed to show light reinforcement when raised in total darkness. The circadian periodicities also differed significantly among the subspecies. Conclusions drawn from the results were: (1) selection for light is genetically influenced as indicated by subspecific differences, (2) some genotypes are readily modified by environmental light conditions than others, and (3) natural selection in each environment appears to contribute to the degree of genetic fixation or genetic plasticity.  相似文献   

16.
Understanding habitat selection by breeding birds and their newly fledged young can be an essential aspect of the conservation of vulnerable species. During 2015–2017, we examined nest site selection of Worthington's marsh wren (Cistothorus palustris griseus) and MacGillivray's seaside sparrow (Ammospiza maritima macgillivraii), and fledgling habitat use by Worthington's marsh wren, 2 imperiled species in northeast Florida, USA. We compared vegetation at unused points to vegetation at nests of both subspecies and at locations used by radio-tagged marsh wren fledglings. Vegetation was taller and stem counts were greater at nest sites compared to unused points. Worthington's marsh wrens also used nest sites with a greater proportion of tall-form smooth cordgrass (Spartina alterniflora) than was observed at unused points. Worthington's marsh wren fledglings also used locations with taller, denser vegetation, but vegetation use changed with fledgling age and tidal stage; older fledglings more frequently used areas with short-form smooth cordgrass and bare ground (and more so during low tides). In contrast, so few nests and nestlings were in black needlerush (Juncus roemerianus) that we could not consider it in our analysis despite its prevalence within our study sites. Our results indicate that tall, dense cordgrass is an important habitat component for these subspecies during the nesting and fledgling life stages in southeastern Atlantic salt marshes.  相似文献   

17.
The Perdido Key beach mouse (Peromyscus polionotus trissyllepsis), Choctawhatchee beach mouse (P. p. allophrys), and St. Andrew beach mouse (P. p. peninsularis) are 3 federally endangered subspecies that inhabit coastal dunes of Alabama and Florida, USA. Conservation opportunities for these subspecies are limited and costly. Consequently, well-targeted efforts are required to achieve their downlisting criteria. To aid the development of targeted management scenarios that are designed to achieve downlisting criteria, we developed a Bayesian network model that uses habitat characteristics to predict the probability of beach mouse presence at a 30-m resolution across a portion of the Florida Panhandle. We then designed alternative management scenarios for a variety of habitat conditions for coastal dunes. Finally, we estimated how much area is needed to achieve the established downlisting criterion (i.e., habitat objective) and the amount of effort needed to achieve the habitat objective (i.e., management efficiency). The results suggest that after 7 years of post-storm recolonization, habitat objectives were met for Perdido Key (within its Florida critical habitat) and Choctawhatchee beach mice. The St. Andrew beach mouse required 5.14 km2 of additional critical habitat to be protected and occupied. The St. Andrew beach mouse habitat objective might be achieved by first restoring protected critical habitat to good dune conditions and then protecting or restoring the unprotected critical habitat with the highest predicted probability of beach mouse presence. This scenario provided a 28% increase in management efficiency compared to a scenario that randomly protected or restored undeveloped unprotected critical habitat. In total, when coupled with established downlisting criteria, these quantitative and spatial decision support tools could provide insight into how much habitat is available, how much more is needed, and targeted conservation or restoration efforts that might efficiently achieve habitat objectives. © 2020 The Wildlife Society.  相似文献   

18.
We studied subspecies, age and environmental effects on constitutive immune function (natural antibody and complement titres, haptoglobin activity and leukocyte concentrations) in Red Knots (Calidris canutus). We compared C. c. islandica and C. c. canutus in the Wadden Sea and found no difference in immune function between subspecies. However, C. c. canutus on their wintering grounds in Banc d’Arguin had higher natural antibody and lower complement levels than C. c. canutus or C. c. islandica in the Wadden Sea. This suggests that immune function is determined more by the surrounding environment than by subspecies. We also compared age classes in the Wadden Sea and found that first year birds had significantly lower natural antibody levels than adults, but that second year birds no longer differed from adults. Finally, we examined the interaction of age and environment in Banc d’Arguin. We found that first year birds (but not adults) in a low quality habitat had higher leukocyte concentrations than first year birds or adults in a high quality habitat. Differences in available resources and defence needs between environments, and differences among individuals differentially distributed between sites, are likely important contributors to the variation in immune function we report. Future studies, which examine these factors on wild birds, will be important for our understanding of how animals function in their natural environment. (220).  相似文献   

19.
The silver‐studded blue, Plebejus subsolanus, is widely distributed in the Russian Altai mountains, northeastern China, the Korean Peninsula, and the Japanese archipelago. In Japan, the species is distributed across wide elevation ranges from the lowlands of Hokkaido to the subalpine zone of Honshu. Current subspecies classification in Japan is as follows: ssp. iburiensis, occurring in lowland grasslands in Hokkaido; ssp. yaginus in lower mountain grasslands in Honshu; and ssp. yarigadakeanus in higher mountain grasslands in Honshu. The habitat of this species has been markedly reduced due to recent habitat destruction and land‐use changes. Here, we undertook phylogeographic analyses of two subspecies, ssp. yaginus and yarigadakeanus in the central mountainous regions of Japan, based on two mitochondrial gene sequences, in order to collect information for establishing effective conservation strategies. From 57 samples from the four mountain ranges, we obtained a haplotype network comprised of 12 haplotypes. Because of the haplotype network topology, the geographic distribution of haplotypes and the correspondence of haplotype divergence to subspecies taxonomy, we provisionally divided the haplotypes into three haplogroups: YR1 and YR2, which comprised ssp. yarigadakeanus, and YG, which comprised ssp. yaginus. Mitochondrial DNA genetic differentiation generally agreed with morphological subspecies classification. The haplotype network suggested that ssp. yarigadakeanus populations had multiple origins, and the subspecies character of “bright blue of the male's wings” was assumed to have evolved independently in each subalpine meadow. We found that P. subsolanus was genetically differentiated depending upon the elevation at each mountain region, suggesting that each haplogroup should be a conservation unit.  相似文献   

20.
Many species of gazelles (Gazella spp.) are nowadays threatened by hunting, poaching, habitat loss and habitat deterioration. Conservation efforts for this group not only face the problem of maintaining remnant populations, but often natural populations have been extirpated from the wild. In some cases, though, captive breeding programs exist that might provide a valuable source for future reintroductions. A major problem in this context is that phylogeographic relationships among different (potentially locally adapted) populations, and even basic phylogenetic relationships between species, are poorly understood, thus hampering the assignment of management units, breeding groups or stocks for reintroduction projects. Our present study focused on Dorcas gazelles (G. dorcas and G. saudiya) from the species’ entire distribution range, with samples originating from western Saharan Africa into Saudi Arabia. In stark contrast to previous studies reporting on pronounced genetic structure in taxa such as Mountain gazelles (G. gazella), we detected low genetic diversity and no evidence for major phylogenetic lineages when analyzing two mitochondrial genetic markers. Using a coalescent approach we infer a steep population decline that started approximately 25,000 years before present and is still ongoing, which coincides with human activities in Saharan Africa. Our phylogenetic analyses, statistical parsimony network analysis and inferred colonization patterns shed doubt on the validity of various described subspecies of G. dorcas.  相似文献   

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