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1.
Aim In recent decades there has been a marked decline in the numbers of African lions (Panthera leo), especially in West Africa where the species is regionally endangered. Based on the climatological history of western Africa, we hypothesize that West and Central African lions have a unique evolutionary history, which is reflected by their genetic makeup. Location Sub‐Saharan Africa and India, with special focus on West and Central Africa. Method In this study 126 samples, throughout the lion’s complete geographic range, were subjected to phylogenetic analyses. DNA sequences of a mitochondrial region, containing cytochrome b, tRNAPro, tRNAThr and the left part of the control region, were analysed. Results Bayesian, maximum likelihood and maximum parsimony analyses consistently showed a distinction between lions from West and Central Africa and lions from southern and East Africa. West and Central African lions are more closely related to Asiatic lions than to the southern and East African lions. This can be explained by a Pleistocene extinction and subsequent recolonization of West Africa from refugia in the Middle East. This is further supported by the fact that the West and Central African clade shows relatively little genetic diversity and is therefore thought to be an evolutionarily young clade. Main conclusions The taxonomic division between an African and an Asian subspecies does not fully reflect the overall genetic diversity within lions. In order to conserve genetic diversity within the species, genetically distinct lineages should be prioritized. Understanding the geographic pattern of genetic diversity is key to developing conservation strategies, both for in situ management and for breeding of captive stocks.  相似文献   

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Two of the eight recognized lion subspecies, North African Barbary lion (Panthera leo leo) and South African Cape lion (Panthera leo melanochaita), have become extinct in the wild in the last 150 years. Based on sequences of mitochondrial DNA (mtDNA) control region (HVR1) extracted from museum specimens of four Barbary and one Cape lion, the former was probably a distinct population characterized by an invariable, unique mtDNA haplotype, whilst the latter was likely a part of the extant southern African lion population. Extinction of the Barbary line, which may still be found in “generic” zoo lions, would further erode lion genetic diversity. Therefore, appropriate management of such animals is important for maintaining the overall genetic diversity of the species. The mtDNA haplotype unique to the Barbary lion, in combination with the small size of the HVR1 analyzed (c. 130 bp), makes it possible and cost-effective to identify unlabelled Barbary specimens kept in museums and “generic” captive lions that may carry the Barbary line. An initial study of five samples from the lion collection of the King of Morocco, tested using this method, shows that they are not maternally Barbary.  相似文献   

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All cat species, except domestic cats, are either threatened or endangered. The Asiatic lion (Panthera leo persica), a critically endangered species, is driven to a single habitat zone in Gir forests in India for its survival. The present status of this big cat compels us to acquire deeper knowledge of its genetic variability and phylogenetic relationships. Here we report the isolation of highly polymorphic microsatellite loci from a partial genomic library of the Asiatic lion. These loci were characterized and have shown high levels of variation ranging from six to 11 alleles per locus in the population studied.  相似文献   

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Lion faecal samples, collected in the field between 1 hour to 1 week after defecation were preserved in three different media (ethanol, ASL buffer and Twostep storage). The aim was to determine which faecal DNA field preservation method best enhances PCR amplification success. Samples stored in ethanol showed a significantly higher amplification success of microsat ellite loci than samples stored in the other two media. In contrast, amplification success of a mitochondrial locus was similar among the samples stored in the three types of media. We reviewed twelve previous studies that employed different media for the storage of faeces, although patterns of success were not fully consistent among different media, ethanol storage was scored high est in the majority of these tests  相似文献   

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A major concern in conservation biology is toavoid inbreeding depression in smallpopulations. Inbreeding has been shown to causeloss of fecundity and reduced survival innatural populations. To predict futureinbreeding levels, given changes in ecologicalconditions, data from large outbred populationsare needed. I use recent population geneticmodels to show how genetic data from such apopulation, combined with ecological data canbe used to predict future changes in levels ofinbreeding. In particular, data from the lion(Panthera leo) is used to simulate theeffect of habitat loss on the future levels ofinbreeding. To do this I used a deterministicpopulation genetics models and anindividual-based stochastic model. Two factorsstand out as particularly important: totalnumber of prides and male dispersal rates. Ifprides are very few (= 10) inbreeding (F)will increase from 0.0 in the initial state to0.26–0.45 after 30 generations, while if thenumber of prides is 100 this level is onlyaround 0.05 assuming no migration into thepopulation. Habitat heterogeneity had onlyminor effects. A reduction in male dispersalfrom their natal territory from 100% to 95%increased the level of inbreedingsubstantially, and never reached below F 0.25 regardless of the number ofprides. Therefore, to sustain a large outbredpopulation of lions, a continuous population ofat least 50 prides, but preferably 100 prides,with no limits to dispersal is required.  相似文献   

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Intraspecific encephalization of the lion and the tiger is investigated for the first time using a very large sample. Using cranial volume as a measure of brain size, the tiger has a larger brain relative to greatest length of skull than the lion, the leopard and the jaguar. The Asian lion has a relatively much smaller brain compared with those of sub-Saharan lions, between which there are few differences. The Balinese and Javan tigers had relatively larger brains compared with those of Malayan and Sumatran tigers, even although these four putative subspecies occupy adjacent ranges in south-eastern Asia. Differences in brain size do not appear to correlate with any known differences in behaviour and ecology and, therefore, may reflect only chance differences in intrageneric and intraspecific phylogeny. However, captive-bred big cats generally have a reduced brain size compared with that of wild animals, so that an animal's life history and living conditions may affect brain size and, hence, functional or environmental explanations should be considered when linking brain size differences to intraspecific phylogenies.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 98 , 85–93.  相似文献   

9.
  • 1 The North African–Asian lion subgroup, which is composed of two subspecies, the Barbary lion, Panthera leo leo, and the Asian lion, P. l. persica, was nearly exterminated during the last centuries. The remaining free‐ranging population of Asian lions consists of c. 350 animals in India. The Barbary lion subsists as captive animals in zoos or circuses, all of which originate from the Moroccan Royal Collection. There have been multiple genetic hybridizations with sub‐Saharan lions.
  • 2 Several incomplete distribution maps of the past occupation of lions were proposed in the literature. I examine the distribution of these lions with the help of a larger database, extracted from zoological, archaeological and historical reports. Some records are however not completely reliable. Data were collected over a long period of time (from the Epipaleolithic to the modern times) in Eurasia, North Africa and the Arabian Peninsula.
  • 3 Dispersal took place in latitudes as far south as 15°N (Yemen) to 18°N (Mali; Chad) and as far north as 45–48°N (Bulgaria); and to longitudes as far west as 5.57°W (Morocco) and as far east as 84°E (India). Expansion was probably constrained by natural ecological factors northwards (higher seasonality, harsher winters) and southwards (extension of aridity after 3000 BP). At latitudes between 40 and 43°N, lions seem to have become a permanent part of the fauna during 6–8 millennia.
  • 4 Lions were brought to extinction by humans through hunting, captures for exhibition in zoos and by the associated natural fragmentation of wild populations. The dates at which extinction took place varied greatly according to the geographical sites: 3000 BC for temperate Europe; 1000 BC in the south of Greece; 12–13th century in the Near East, Arabian Peninsula, Trans‐Caucasia or north of Afghanistan; and 19–20th century for North Africa, the Middle East and India.
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10.
The relationship between the spatiotemporal distribution of resources and patterns of sociality is widely discussed. While the resource dispersion hypothesis (RDH) was formulated to explain why animals sometimes live in groups from which they derive no obvious benefits, it has also been successfully applied to species that benefit from group living. Some empirical tests have supported the RDH, but others have not, so conclusions remain equivocal and further research is required to determine the extent to which RDH predictions hold in natural systems. Here, we test four predictions of the RDH in an African lion population in the context of their fission–fusion society. We analyzed data on group composition of GPS‐collared lions and patterns of prey availability. Our results supported the first and second predictions of the RDH: Home range size (a) was independent of group size and (b) increased with distance between encounters with prey herds. Nonetheless, the third and fourth RDH predictions were not supported: (c) The measure of resource heterogeneity and (d) resource patch richness measured through prey herd size and body size had no significant effect on lion group size. However, regarding the fourth prediction, we added an adaptation to account for dynamics of fission–fusion society and found that the frequency of pride fission increased as group size increased. Our data set restricted us from going on to explore the effect of fission–fusion dynamics on the relationship between group size and patch richness. However, this should be investigated in future studies as including fission–fusion dynamics provides a more nuanced, realistic appreciation of lion society. Our study emphasizes the importance of understanding the complexity of a species' behavioral ecology within the framework of resource dispersion. Whatever larger theoretical framework may emerge to explain lion society, incorporating fission–fusion dynamics should allow the RDH to be refined and improved.  相似文献   

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大型食肉动物对维持生态系统的结构和功能具有重要作用, 但大部分大型食肉动物处在持续的种群数量和分布面积下降之中, 面临着急迫的研究与保护需求。华北豹(Panthera pardus japonensis)是我国特有的豹亚种, 也是部分区域森林生态系统中仅存的大型食肉动物, 面临着生境破碎化等威胁。本研究使用红外相机调查了宁夏六盘山国家级自然保护区华北豹的分布, 通过构建占域模型分析了华北豹的栖息地利用, 预测了华北豹的适宜栖息地, 并评估了其生境破碎化格局。研究发现, 华北豹在六盘山的平均占域率约为0.135。华北豹偏好植被发育成熟、地势崎岖、温度较低、远离农田和公路的栖息地, 对于农田边缘和居民点等人类活动区域未显示出显著回避。研究识别的六盘山华北豹适宜栖息地主要沿六盘山东西两侧山脉分布, 55%的适宜栖息地斑块位于六盘山国家级自然保护区内。栖息地斑块面积平均为16 km2, 最大达214 km2, 约77%的栖息地斑块面积在10 km2以下。研究表明六盘山国家级自然保护区有效地保护了华北豹现有的适宜栖息地, 但仍存在栖息地破碎化和人类活动干扰等关键限制因素。建议通过栖息地改造、人类活动管理等方式增强六盘山华北豹适宜栖息地斑块连通性; 并通过推动华北豹跨省保护工作等举措促进华北豹种群扩散恢复。  相似文献   

13.
We examined sequence variation in the mitochondrial cytochrome b and NADH dehydrogenase subunit 5 genes (2,360 bp total) for 26 lions from eleven locations throughout sub-Saharan Africa. Six distinct haplotypes were observed in the combined sequences, forming two clades: the eastern and the western savannas. The Uganda-Western Kenya haplotype grouped at a basal position with the eastern clade of lions from Tsavo south to the Transvaal and Natal regions. The phylogenetic position of the haplotype from Sabi Sands in the southern part of Kruger National Park remained poorly resolved. The haplotypes found in Namibia and Botswana formed the western clade. The modest genetic variation documented here argues against taxonomic distinctions among living African lions.  相似文献   

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Many species have already experienced distributional shifts due to changing environmental conditions, and analyzing past shifts can help us to understand the influence of environmental stressors on a species as well as to analyze the effectiveness of conservation strategies. We aimed to (1) quantify regional habitat associations of the California gnatcatcher (Polioptila californica ); (2) describe changes in environmental variables and gnatcatcher distributions through time; (3) identify environmental drivers associated with habitat suitability changes; and (4) relate habitat suitability changes through time to habitat conservation plans. Southern California's Western Riverside County (WRC ), an approximately 4,675 km2 conservation planning area. We assessed environmental correlates of distributional shifts of the federally threatened California gnatcatcher (hereafter, gnatcatcher) using partitioned Mahalanobis D 2 niche modeling for three time periods: 1980–1997, 1998–2003, and 2004–2012, corresponding to distinct periods in habitat conservation planning. Highly suitable gnatcatcher habitat was consistently warmer and drier and occurred at a lower elevation than less suitable habitat and consistently had more CSS , less agriculture, and less chaparral. However, its relationship to development changed among periods, mainly due to the rapid change in this variable. Likewise, other aspects of highly suitable habitat changed among time periods, which became cooler and higher in elevation. The gnatcatcher lost 11.7% and 40.6% of highly suitable habitat within WRC between 1980–1997 to 1998–2003, and 1998–2003 to 2004–2012, respectively. Unprotected landscapes lost relatively more suitable habitat (?64.3%) than protected landscapes (30.5%). Over the past four decades, suitable habitat loss within WRC , especially between the second and third time periods, was associated with temperature‐related factors coupled with landscape development across coastal sage scrub habitat; however, development appears to be driving change more rapidly than climate change. Our study demonstrates the importance of providing protected lands for potential suitable habitat in future scenarios.  相似文献   

17.
This study examined population density, habitat and diet of Dasyatis marianae, a recently discovered species, in the reef complex of Maracajaú in Rio Grande do Norte state, Brazil. The highest concentration of D. marianae occurred in seagrass beds. Habitat use differed significantly between sex and age classes, with females and juveniles using areas other than reefs. Females utilized primarily seagrass beds and juveniles occurred mainly along the sandy bottom near the beach, highlighting the importance of protecting these areas. Dasyatis marianae diet was characterized primarily by crustaceans (91·9% index of relative importance, IRI), including shrimp, crabs and lobsters. The availability of prey in different habitat types influences occupation by D. marianae, but the prey selectivity of D. marianae, among other factors, may affect this relationship. Intense shrimp and lobster fishing in the region probably has an effect on preferred prey resources of this ray. Information on feeding habits of this species contributes to a better understanding of trophic dynamics and food webs, which is critical if ecosystem principles are to be integrated into fisheries management.  相似文献   

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Many species of vertebrates require multiple habitats to obtain different resources at different stages of their life-cycles. Use of habitat mosaics takes place on a variety of spatial and temporal scales, from a daily requirement for adjacent habitats to seasonal use of geographically separated environments. Mosaics of habitats are also required in some species to allow ontogenetic habitat shifts, while in others each sex may have specific requirements that are met by different habitats. The extent and nature of animal movements are key (but generally poorly known) factors affecting the vulnerability of species to landscape change. The requirement by many species for multiple habitats suggests that their conservation will be most effective in a mosaic environment and that protection of certain high profile habitats alone, such as rainforest, will be insufficient to achieve conservation goals. Management regimes that result in homogenization of habitats should be avoided. Priority should be given to research that identifies the extent to which species can locate habitat mosaics, at different spatial scales and arrangements, in modified environments.  相似文献   

20.
Land snails are an important yet often neglected component of Australia's biological diversity. Despite high levels of diversity within this group and the identification of many narrow range endemic species as being of conservation concern, there have been few detailed studies that document the ecology and conservation requirements of the group. A range of threats has been suggested, yet relatively few have been rigorously assessed. Whilst factors such as land clearing are readily apparent and have resulted in extinctions, other threats such as climate change are not well understood. This paper reviews studies conducted on terrestrial molluscs in Australia and highlights the need for further targeted ecological research, given the likely level of on-going threats. We urge researchers to apply rigorous approaches to data collection that will enable a deeper understanding of the factors governing distribution and abundance. Approaches used in other areas of conservation biology offer considerable scope for application to land snails and for the development of appropriate conservation strategies.  相似文献   

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