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《African Zoology》2013,48(3):83-97
Throughout the Miocene, the African landscape underwent broad climatic shifts that profoundly influenced the distribution of fauna and flora. Since the late Miocene, these shifts have created a landscape in southern Africa that is strongly characterised by savanna and arid environments. Forests persist in small fragments, primarily in mountainous or heterogeneous landscapes. Arthroleptis wahlbergii is a small frog endemic to eastern South Africa that has presumed low dispersal ability. Because of its preference for forests, the dynamics of forests since the late Miocene in this region might have promoted diversification within A. wahlbergii. To investigate whether habitat fragmentation might have driven divergences among populations, we carried out species distribution modelling and population level and phylogenetic analyses using two genetic loci (16S, mitochondrial; RAG-1, nuclear) sequenced for 48 individuals from 14 forests across the c. 500 km range of this species. There is substantial population-level structuring within A. wahlbergii, however the structure does not relate to forest types or catchments. We instead propose that the structure is a result of dynamic and idiosyncratic changes in forest connectivity over the Pleistocene. We identified two geographically circumscribed clades, the northern of which corresponds to true A. wahlbergii. The southern clade corresponds to populations from which Arthroleptis wageri FitzSimons, 1930 was described. This has long been considered a synonym of A. wahlbergii, but our molecular phylogenetic and distribution modelling supports recognising A. wageri as a distinct species. 相似文献
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Son Truong NGUYEN Masaharu MOTOKAWA Tatsuo OSHIDA Hideki ENDO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):187-198
Southeast Asia is a region of high biodiversity, containing species of plants and animals that are yet to be
discovered. In this region, bats of the subfamily Kerivoulinae are widespread and diverse with six species
recorded in Vietnam. However, the taxonomy of the Kerivoulinae in Asia is complicated. In our study, we used
diagnostic characters and multivariate analysis to determine morphological differences between the genera
Kerivoula and Phoniscus. We showed that the two genera are distinguishable
by the size of second upper incisors, the shape of skull, nasal sinus, canines, second upper and lower
premolars. In addition, the two genera can be osteometrically separated by measurements of the braincase
height, interorbital width and shape of anterior palatal emargination. Our data clearly revealed the
morphological variations in the skull shape of Kerivoula hardwickii in Vietnam. This suggests
a possible separation into three morphotypes, representing cryptic species supported by statistical
differences with wide variation in skull shape, size and teeth. These results demonstrated Kerivoula
hardwickii can be separated three subspecies, and the result will serve as the basis for the future
assessment and classification of this group in Southeast Asia. 相似文献
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Metlholo Andries Phukuntsi Helene Brettschneider Desiré L Dalton Teresa Kearney Jacqueline Badenhorst Antoinette Kotze 《African Zoology》2016,51(1):69-76
DNA barcoding has been proposed as a method for species identification. However, this method has been criticised for its over-reliance on a single mitochondrial gene. In this study, four mitochondrial gene regions and one nuclear gene region were used to investigate their different abilities to identify tissue associated with museum specimens of Aethomys chrysophilus, Aethomys ineptus and Micaelamys namaquensis. Aethomys chrysophilus and the more recently elevated A. ineptus are indistinguishable on morphological grounds; however, their ranges are largely parapatric with only one syntopic locality currently known. All of the mitochondrial gene regions were able to separate M. namaquensis from A. chrysophilus and A. ineptus, but they varied in their abilities to resolve differences between A. chrysophilus and A. ineptus. The sequence results identified a specimen from KwaZulu-Natal that was misclassified and should have been identified as A. ineptus. Seven specimens that had not been reclassified following the elevation of A. ineptus to species level were identified as A. ineptus. Individuals of A. chrysophilus from Malawi could not be classified as either A. chrysophilus or A. ineptus, and may be a hybrid or a new, distinct species. This study indicates that DNA barcoding may be used to separate M. namaquensis from A. chrysophilus and A. ineptus, and although it was not able to separate A. chrysophilus and A. ineptus, it did indicate specimens from Malawi may be a new cryptic species. 相似文献
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《Human Dimensions of Wildlife》2012,17(3):199-216
ABSTRACTDefinitions of “species” are complex and often contested in the scientific literature. Hybridization between species, a natural phenomenon exacerbated by climate change, can blur lines between species historically considered distinct by the public and existing management regimes. Perceptions and valuations about hybridized species may have significant implications for conservation of both hybrids and parent species. An internet survey of US residents (n = 500) recruited via Mechanical Turk was used to explore public understanding of species distinctions and hybridization in grizzly and polar bears. Participants ranked factors they would use for categorizing a hybrid bear and responded to qualitative and quantitative items about perceptions of both parent species and hybrid offspring. Findings suggested that perceptions and categorizations of hybrids differ from those of parent species and may be influenced by a number of personal and contextual factors, with potential consequences for future conservation and management. 相似文献
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《Integrative zoology》2017,12(3):186-197
The involvement of communities in ecological studies has been shown to augment conservation efforts, especially for cryptic species. However, there is a lack of studies addressing the utility of incidental sighting records from community members in gaining knowledge on habitat preferences and distribution of suitable habitat for these organisms. This study compares preferences of the Lumholtz's tree kangaroo (Dendrolagus lumholtzi ; LTK), a cryptic rainforest folivore in northeastern Australia, for various habitat and climatic variables derived from data collected during scientific projects to those derived from incidental sighting records using ArcGIS and Maxent. Incidental sighting records suggest that the species uses a wider range of altitudes, annual rainfalls, annual mean temperatures and vegetation types than predicted by scientific studies. Incidental records also show that the species can persist in areas of lower rainfall during the wettest month and lower minimum temperature during the coldest month. Both data place the species within a comparable range of rainfalls during the driest month, maximum temperatures of the warmest month and soil types. When using identified preferences to assess the extent and distribution of suitable habitat, incidental records predicted more areas of suitable habitat than scientific records with an overlap of up to 91% between them. The present study proves that incidental sighting records can be a valuable part of the study of cryptic species and should be considered complementarily alongside scientific studies to obtain comprehensive ecological information of a species that can assist in its conservation. 相似文献
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由于最早记载苜蓿的典籍没有明示其是紫花还是黄花,导致对我国古代苜蓿物种认识上存在分歧,目前大致有5种观点:一是古代苜蓿专指紫花苜蓿;二是南苜蓿;三是紫苜蓿与南苜蓿的合称;四是黄花苜蓿;五是不确定。本研究应用植物考据学原理,通过收集整理记载苜蓿植物生物学的典籍,结合近现代研究成果,考证苜蓿物种。研究表明,汉代从大宛国传入我国的苜蓿与紫花苜蓿的起源地相一致,并且唐代韩鄂《四时纂要》明确记载了苜蓿开紫花,主要分布在黄河流域,这与我国汉代苜蓿最初引种地相一致,在之后也有不少典籍同样记述了苜蓿开紫花,乃至苜蓿的生态生物学特性。可以确定,我国汉代引入的苜蓿应该是开紫花的苜蓿,即紫花苜蓿。宋梅尧臣和明李时珍记述的开黄花的苜蓿,至少说明在宋代和明代开黄花的苜蓿就在我国存在和被利用。据清《植物名实图考》记载,在古代我国有3种苜蓿被利用,即紫花苜蓿、南苜蓿和黄花苜蓿。 相似文献
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This review investigates the disordered status of the classification of Medicago genus,both domestically and internationally. Several definitions of a taxonomic species were considered and the names and characteristics of 13 Medicago species in China are reported,together with a detailed summary of the names,life forms,chromosome numbers,pollination methods and natural distribution of about 90 Medicago species worldwide,including the classification of 14 sections and 10 subsections in Medicago. The molecular evolutionary relationships between different species,and the geographical origin of Medicago are discussed,and the genetic relationships between different subspecies in the alfalfa complex are further explained. This study puts forward a method of identifying Medicago species on the basis of deep understanding of the concept of species. A wide collection of global Medicago germplasm resources,aiming to further clarify the evolutionary relationship among different sections and different species by molecular evolution methods is proposed. This review provides a reference framework for future Medicago classification and alfalfa cross breeding. © 2022 Editorial Office of Acta Prataculturae Sinica. All rights reserved. 相似文献
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11类哺乳类和鸟类动物红细胞免疫功能的对比研究 总被引:23,自引:0,他引:23
应用红细胞C3b受体花环(C3bRR)和免疫复合物花环(ICR)试验,证实鸽、鹌鹑、鹅、鹿、瘤牛、牦牛、德宏水牛(沼泽型水牛)、摩拉水牛(江河型水牛)、驴、小耳猪和山羊红细胞表面存在补体C3b受体(C3breceptor,C3bR),表明红细胞免疫系统(Redcellimmunesystem,RCIS)的概念亦适用于这11类动物。文中对红细胞C3bRR和ICR分别代表红细胞表面C3bR“空位”和“占位”状态的会意做出了解释。对11类动物中哺乳类与鸟类动物红细胞C3bRR和ICR测试的统计结果进行剖析,可知:总体上讲,3种鸟类红细胞表面补体C3bR活性显著小于8类哺乳动物(P<0.05,有少数例外),而红细胞粘附免疫复合物能力则极显著地大于8类哺乳动物(P<0.01);红细胞粘附免疫复合物能力和其表面C3bR活性在不同动物种、型间有相当的差异。 相似文献