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1.
光肩星天牛两型种群表型多样性分析   总被引:1,自引:0,他引:1  
【目的】光肩星天牛Anoplophora glabripennis(Motschulsky)是国内最重要的林木蛀干害虫之一,在中国分布范围较广。近年来,形态学以及分子生物学的研究表明,光肩星天牛与黄斑星天牛A.nobilis(Ganglbauer)很可能是同一种的不同型。定量研究光肩星天牛两型的差异与表型多样性。【方法】作者以光肩星天牛的20个地理种群的光肩星天牛分布区为研究对象,采用巢式方差分析和聚类分析对其头长、头后缘宽、前胸后缘宽等13个表型性状进行多样性分析。【结果】表型特征在群体间与群体内均存在着广泛的变异,13个性状的平均表型分化系数为11.78%,群体内变异是其表型性状变异的主要来源;后翅长度与经度呈极显著负相关,与海拔极显著正相关以及与年降水量呈显著负相关。体长与鞘翅斑纹颜色与海拔高度分别呈显著正相关和负相关关系;在不同地理种群中,鞘翅斑纹颜色的分化系数达到最大,为50.53%;而以鞘翅斑纹颜色分类的两型差异显示各性状的表型分化系数均大幅度降低。【结论】本研究首次将鞘翅斑纹的颜色进行数字化处理,并进行分类,结果显示各个颜色类群的分化系数均大幅度减小,说明颜色类群之间的分化要小于地理隔离所造成的差异,进一步验证了光肩星天牛与黄斑星天牛为同一种的不同型。  相似文献   

2.
Nuclear DNAs extracted from individuals of the kelpCostaria costata (Phaeophyta) were studied using a small-subunit ribosomal DNA probe (pCc 18). On the basis of annealing analysis of rDNA variation within and among individuals and between populations, polymorphisms detected by pCc 18 appeared to indicate population identity. These rDNA polymorphisms were used to chart the distribution ofCostaria breeding groups in the northeast Pacific. 20 sites were sampled and eight distinct populations resolved. One variant (Variant A) identified a southern group with plants from 13, loosely clustered sites sharing this banding pattern. The other seven variants, found in the northern portion of the study area, were unique and population-specific.  相似文献   

3.
In Pterostichus melanarius, the seasonal dynamics of activity is characterized by two peaks (in mid-June-early July and in late July-mid-August). In southwestern Moldova, these peaks were registered twenty days later than in Moscow Province. In both regions, larvae and adults hibernate. Both hibernated immature adults and adults that had already bred before wintering start reproduction simultaneously. In hibernated immature individuals, the average number of eggs per female constituted 1.5 times that in the postgenerative females. In the steppe zone, the total number of eggs laid by immature females was closed to that laid by previously bred females, while in the southern taiga zone, hibernated immature females laid a greater number of eggs. In the steppe zone, females of a new generation lay a somewhat lower number of eggs in comparison with hibernated immature females, whereas the total number of laid eggs is significantly higher. In the southern taiga zone, both the average number of laid eggs and their total number are equal in females of a new generation and hibernated immature females. In Moldova, the majority of individuals of a new generation breed in the current season, whereas in Moscow Prov., about half the individuals hibernate without breeding. Over the largest part of the range, the life cycle of P. melanarius combines the one-year development with hibernating larvae with two-year development with the hibernating immature and postgenerative adults. The two subpopulation groups, wintering at different phases of the ontogenesis, are totally isolated at the northern border of the range. Within each subpopulation., individuals are characterized by the biennial life cycle; as a result, the polyvariant character of the life cycle turns into the monovariant one. We suggest that such a life cycle should be designated as the compensatory monovariant cycle, and populations, in which it is realized, as byside populations (from the English “side by side”).  相似文献   

4.
Two new species of the weevil genus Mecysmoderes Schoenherr, 1837 are described from Vietnam. Mecysmoderes (Enzoellus) vladimirisp. n. differs from the type species of Enzoellus and its allies from Thailand and Laos in the larger size, deeper meshes on the pronotum, broader legs and a velvety black sutural spot on the elytra. Mecysmoderes (Xenysmoderes) sergiisp. n. in the shape, coloration, and vestiture of the body is similar to M. consularis Pascoe, but clearly differs in the larger size, strongly and unevenly convex pronotal disc, swollen in the middle part elytra, and a dark scutellar spot.  相似文献   

5.
This study describes and quantifies morphological valve traits of the ostracod Limnocythere rionegroensis from Patagonian steppe lakes and explores their association with lake water characteristics. Surface ornamentation was examined by scanning electron and transmitted light microscopy, and valve size and shape were analyzed using morphometric techniques. Limnocythere rionegroensis shows remarkable variations in surface ornamentation, based on which three morphotypes (MI, MII, and MIII) were identified. Valves of morphotypes MI and MIII are larger, show slight to moderate external reticulation, and a higher shape variability, whereas MII is characterized by a very conspicuous reticulation, lower shape variability, and smaller valves. Outline analysis yielded a great shape disparity related to the dorsal margin slope. MI was found in sexual populations from euhaline to mesohaline ephemeral lake; MII occurs in parthenogenetic populations from mesohaline to oligohaline permanent or ephemeral lakes; and MIII, from both sexual and asexual populations, inhabits a broad range of environmental conditions in terms of salinity and stability. Limnocythere rionegroensis intraspecific variations may be caused by environmental parameters and genetic factors associated to reproductive strategies. These results contribute to the knowledge of extant L. rionegroensis morphological variability and provide additional clues to improve the environmental interpretation of fossil assemblages.  相似文献   

6.
Zones of contact between divergent biological forms within or between species are critical to the study of speciation. How characters flow across contact zones can be informative of the speciation process. To better understand this phenomenon in a mammal, we investigated cranial shape change in a contact zone between northern and southern phylogeographical groups of California voles (Microtus californicus). We took 12 linear measurements of skulls, one measurement of the mandible, and coded the presence and absence of two skull foramina for 427 specimens. In multivariate analyses, skulls within parental regions were correctly assigned more than 90% of the time. In the contact zone, 49% were classified as northern and 51% as southern, with a bimodal distribution of posterior probability values. Foraminal patterns in the contact zone were intermediate between northern and southern regions. A cline analysis for coastal populations suggested a similar centre for mitochondrial and nuclear markers, although a centre for the morphological data was offset. Cranial morphology indicates an intermediate area with overlap between the two regions, as suggested by the molecular data, with a pattern distinct from mitochondrial DNA or nuclear DNA markers. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 104 , 264–283.  相似文献   

7.
Marin, J., Crouau‐Roy, B., Hemptinne, J.‐L., Lecompte, E. & Magro, A. (2010). Coccinella septempunctata (Coleoptera, Coccinellidae): a species complex? —Zoologica Scripta, 39, 591–602. Coccinella septempunctata L., the seven spot ladybird is widely distributed across the Paleartic region. Based on a few morphological characteristics and geographical origin, some populations are recognized as distinct species, e.g., the North African Coccinella algerica Ková? and Japanese Coccinella brucki Mulsant later considered to be a subspecies –C. septempunctata brucki. The objective of this study is to discuss the taxonomic status of the seven spot ladybird, in particular whether it is a complex of species or the same species throughout the Paleartic region. The relationship between populations was clarified by using a combination of molecular and limited morphometric data and assessing potential reproductive barriers by means of cross breeding. Although there is considerable variation in the size of the spots on the elytra, the results of this study confirm that all studied populations belong to the same species.  相似文献   

8.
Buran-Kaya III (Crimea, Ukraine) is a unique site, with a stratigraphy from Middle to Final Palaeolithic. The Gravettian layers 5-2, 6-1 and 6-2 of this site yielded numerous lithic and bone industries, ornaments from marine and freshwater shells, mammal teeth and mammoth ivory, human fossils and abundant faunal remains. Аccording to the stylistic indications of the lithic and bone inventories, the settlements of layers 5-2, 6-1 and 6-2 of Buran-Kaya III represent local variants of the Gravettian in Crimea and in mainland Ukraine and, therefore, the existence of separately social communities. Conversely, ornament objects and human remains (with specific mortuary practices) of Buran-Kaya III may suggest extensive social contacts of its Gravettian inhabitants with other human populations from mainland Ukraine. These hypotheses make necessary future investigations about the social organisation of the Epigravettian societies in Eastern Europe.  相似文献   

9.
Summary A comparative study of frequencies and types of Q-polymorphic variants in seven autosome pairs (3, 4, 13–15, 21, and 22) was performed in three steppe Mongoloid populations of Central Asia (Kazakhs, Dunghans, Mongolians) and three highland Kirghiz populations of Pamir and Tien-Shan. The three steppe Mongoloid populations showed statistically significant homogeneity both in the frequency of Q-polymorphic variants and the distribution of homo- and heteromorphs, with complete agreement of observed frequencies with those theoretically predicted by the law of Hardy-Weinberg. Similar homogeneity was revealed in the three highland Kirghiz populations of Pamir and Tien-Shan. However, comparative analysis of highland and steppe Mongoloids revealed significant differences in the following variables: (1) mean number of Q variants per individual, 2.50 and 3.49 in the highland and steppe populations, respectively; (2) frequency of Q variants in 7 of the 12 autosomes studied; and (3) distribution of homo- and heteromorphs in four autosomal pairs (13–15, 21) with a preponderance of individuals with increased homomorph (-/-) frequency in highlanders.The following questions are discussed: (1) the possible selective value of chromosomal Q-heterochromatin material in the adaptation of human populations to extreme environmental factors, in particular to the high-altitude environment of Pamir and Tien-Shan; (2) the existence of intraracial heterogeneity in Mongoloids living in different ecological zones; and (3) the possible taxonomic value of Q-variant inversion in chromosome 3.  相似文献   

10.
Analysis of a 551-bp segment of the mitochondrial DNA control region in 23 individuals from nine populations of Dolly Varden from Sakhalin and three individuals from the Shikaribetsu Lake (Hokkaido) revealed the presence of seven haplotypes of southern form, along with one haplotype of northern form of Dolly Varden. All seven haplotypes of southern Dolly Varden were earlier described in the populations from Hokkaido. Hierarchical analysis of molecular variance (AMOVA) based on the haplotype frequencies, performed using literature data, suggested that, during the glacial epoch, there were three regional population groups of Dolly Varden (from eastern and western coasts of Sakhalin, and from Southern Primorye). Population groups from Sakhalin and Primorye were clearly separated. The differences between two Sakhalin population groups in the mtDNA haplotype frequencies were not statistically significant. However, relative to the earlier obtained data on microsatellite loci, these differences were statistically significant. For the populations of Sakhalin Dolly Varden, the data on mitochondrial and microsatellite DNA variation supplement each other.  相似文献   

11.
As a result of allozyme analysis, Nei’s genetic distances were determined between the phylogeographic group of seven populations of Pinus sylvestris L. in the “glacial” zone of the range in Central Yakutia and 25 populations of its hypothetical Pleistocene refugia of the southern nonglacial zone within the entire range of the species in Northern Eurasia. The location of the most likely “avant-garde” refugium of the modern yakutian populations of the Scots pine is Northern Priamur’e (Tynda), as well as less likely Siberian (Romanovka, Irkutsk), South Ural (Kryktytau), and Central European (the Czech Republic) refugia.  相似文献   

12.
The geology and climate of the western Mediterranean area were strongly modified during the Late Tertiary and the Quaternary. These geological and climatic events are thought to have induced changes in the population histories of plants in the Iberian Peninsula. However, fine-scale genetic spatial architecture across western Mediterranean steppe plant refugia has rarely been investigated. A population genetic analysis of amplified fragment length polymorphism variation was conducted on present-day, relict populations of Ferula loscosii (Apiaceae). This species exhibits high individual/population numbers in the middle Ebro river valley and, according to the hypothesis of an abundant-centre distribution, these northern populations might represent a long-standing/ancestral distribution centre. However, our results suggest that the decimated southern and central Iberian populations are more variable and structured than the northeastern ones, representing the likely vestiges of an ancestral distribution centre of the species. Phylogeographical analysis suggests that F. loscosii likely originated in southern Spain and then migrated towards the central and northeastern ranges, further supporting a Late Miocene southern-bound Mediterranean migratory way for its oriental steppe ancestors. In addition, different glacial-induced conditions affected the southern and northern steppe Iberian refugia during the Quaternary. The contrasting genetic homogeneity of the Ebro valley range populations compared to the southern Iberian ones possibly reflects more severe bottlenecks and subsequent genetic drift experienced by populations of the northern Iberia refugium during the Pleistocene, followed by successful postglacial expansion from only a few founder plants.  相似文献   

13.
Ma L  Xue Y  Liu Y  Wang Z  Cui X  Li P  Fu S 《Hereditas》2005,142(2005):103-111
It has been shown that the variants of alcohol dehydrogenase (ADH) genes exhibit great diversities among various populations and are associated with susceptibility to alcoholism. To investigate the distribution of SNPs at ADH genes in Chinese populations and the genetic relationship of these groups, we collected 467 individuals from 15 groups distributing widely from north to south in China and genotyped 7 SNPs at ADH genes respectively. The statistic analyses of allele frequencies, estimated haplotype frequencies, pairwise linkage disequilibrium, AMOVA (analysis of molecular variance), pairwise Fst', and cluster analysis indicated (1) that six of these seven SNPs showed great variations in the 15 Chinese populations, and three of them (RsaI, SspI, EcoRI), were confirmed to be informative SNPs. However, the causative SNP ADH1B Arg47His confirmed in case-control studies could not act as significant indicator to distinguish bibulous groups from non-bibulous groups in healthy individuals; (2) haplotypes constructed with ADH SNPs could be used as markers to discern different populations in China, and six-allele haplotype "221211" was the most common one defined in present study; (3) on the basis of SNPs analysis of ADH genes, the 15 populations were grouped into northern groups and southern groups. Moreover, the origin relationship among the populations was indicated according to the results of cluster analysis.  相似文献   

14.
Continuing study on the Chinese species of Phygasia Chevrolat, 1836 revealed 10 specimens collected from Taiwan that were distinctly different from other described species within this genus. The new species is similar to P. ornata Baly, 1876 and P. pseudornata Wang et Yang, 2008, but can be distinguished from them by the color and position of elytra markings as well as the shape of male genitalia: the black markings on the elytra only covered the humeral area and the sub-apical area of elytra, and genitalia of male pointed and short with big basal opening. A new species, Phygasia taiwanensis sp. n., is described herein.  相似文献   

15.
A list of 30 species of the family Tabanidae recorded in Belgorod Province is provided, and data on the landscape-zonal distribution, typical biotopes, and dates of flight in the region are given for each species. The greatest number of horsefly species (24) was recorded in the southern forest-steppe subzone, and smaller numbers, in the central forest-steppe subzone (18) and the steppe zone (16). Half of the forest and forest-steppe species extend into the steppe zone while some southern species penetrate into the forest-steppe zone. The pattern of horsefly distribution is determined by the biotopic conditions. The boundaries of distribution of individual species do not distinctly correspond to those of the landscape subzones.  相似文献   

16.
The beet webworm, Loxostege sticticalis L., is a very dangerous polyphagous insect pest whose outbreaks periodically occur in southern Russia and northern China. The aim of our work was to describe the photoperiodic response of beet webworm populations from western (Krasnodar Territory and Rostov Province) and eastern [Buryatia and China (Hebei Province)] parts of the pest range. The insects were reared under constant photoperiods of 12–18 h and constant temperatures of 19–25°C. Incidence of diapause at different photoperiods did not show any considerable geographic differences, and the critical day length at which 50% of prepupae arrested their development was about 14–15 h in all the populations studied at experimental temperatures. The results obtained agree with the hypothesis on the existence of an area (or areas) where the pest survives during adverse periods and wherefrom it spreads when an outbreak begins (Saulich et al., 1983; Goryshin et al., 1986). Presumably, the larger part of the pest native habitats (to the north of the steppe zone) is occupied by temporary populations, incapable of surviving for long periods without an inflow of migrants from more southerly steppe regions.  相似文献   

17.
The Common Bush-Tanager (Chlorospingus ophthalmicus) is distributed in Neotropical cloud-forests from Mexico to Argentina and contains 25 subspecies divided into eight subspecies groups based on biogeography, eye coloration, presence of a postocular spot and chest band. All of Central America is occupied by a single subspecies group; whereas the Andes are believed to be occupied by seven additional subspecies groups. We used five mitochondrial genes to investigate the phylogeography and possible species limits of the ophthalmicus complex. A total of 14 monophyletic lineages were uncovered within the ophthalmicus complex, including three clades currently classified as separate species (C. semifuscus, inornatus and tacarcunae). Divergence estimates for these clades date between 0.8 and 5.2 million years ago (Ma). Contrary to expectations based on morphological diversity, phylogeographic structure was greatest in Mexico and Central America and weakest in the Andes. Morphological and genetic divergences were not significantly correlated and most morphologically defined subspecies groups were not supported. Our evidence suggests the ophthalmicus complex originated in Mexico ca. 6.0 Ma (million years ago) and spread south into the Andes ca. 4.7 Ma before the completion of the Isthmus of Panama. Three genetically divergent lineages of ophthalmicus that formed in the Andes possess a complex checkerboard distribution, with a single lineage represented by disjunct populations from Venezuela and the southern Andes, while intervening populations in Ecuador and Central Peru form two genetically and morphologically divergent lineages.  相似文献   

18.
At the Last Glacial Maximum (LGM), the southern European peninsulas were important refugia for temperate species. Current genetic subdivision of species within these peninsulas may reflect past population subdivision at the LGM, as in ‘refugia within refugia’, and/or at other time periods. In the present study, we assess whether pygmy shrew populations from different regions within Italy are genetically and morphologically distinct. One maternally and two paternally inherited molecular markers (cytochrome b and Y‐chromosome introns, respectively) were analysed using several phylogenetic methods. A geometric morphometric analysis was performed on mandibles to evaluate size and shape variability between populations. Mandible shape was also explored with a functional approach that considered the mandible as a first‐order lever affecting bite force. We found genetically and morphologically distinct European, Italian, and southern Italian groups. Mandible size increased with decreasing latitude and southern Italian pygmy shrews exhibited mandibles with the strongest bite force. It is not clear whether or not the southern Italian and Italian groups of pygmy shrews occupied different refugia within the Italian peninsula at the LGM. It is likely, however, that geographic isolation earlier than the LGM on islands at the site of present‐day Calabria was important in generating the distinctive southern Italian group of pygmy shrews, and also the genetic groups in other small vertebrates that we review here. Calabria is an important hotspot for genetic diversity, and is worthy of conservation attention. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100 , 774–787.  相似文献   

19.
The Patagonian steppe is an immense, cold, arid region, yet phylogeographically understudied. Nassauvia subgen. Strongyloma is a characteristic element of the steppe, exhibiting a continuum of morphological variation. This taxon provides a relevant phylogeographical model not only to understand how past environmental changes shaped the genetic structure of its populations, but also to explore phylogeographical scenarios at the large geographical scale of the Patagonian steppe. Here, we (1) assess demographic processes and historical events that shaped current geographic patterns of haplotypic diversity; (2) analyze hypotheses of isolation in refugia, fragmentation of populations, and/or colonization of available areas during Pleistocene glaciations; and (3) model extant and palaeoclimatic distributions to support inferred phylogeographical patterns. Chloroplast intergenic spacers, rpl32–trnL and trnQ–5′rps16, were sequenced for 372 individuals from 63 populations. Nested clade analysis, analyses of molecular variance, and neutrality tests were performed to assess genetic structure and range expansion. The present potential distribution was modelled and projected onto a last glacial maximum (LGM) model. Of 41 haplotypes observed, ten were shared among populations associated with different morphological variants. Populations with highest haplotype diversity and private haplotypes were found in central‐western and south‐eastern Patagonia, consistent with long‐term persistence in refugia during Pleistocene. Palaeomodelling suggested a shift toward the palaeoseashore during LGM; new available areas over the exposed Atlantic submarine platform were colonized during glaciations with postglacial retraction of populations. A scenario of fragmentation and posterior range expansion may explain the observed patterns in the center of the steppe, which is supported by palaeomodelling. Northern Patagonian populations were isolated from southern populations by the Chubut and the Deseado river basins during glaciations. Pleistocene glaciations indirectly impacted the distribution, demography, and diversification of subgen. Strongyloma through decreased winter temperatures and water availability in different areas of its range.  相似文献   

20.
【目的】定量比较中国及周边国家地区白星花金龟 Protaetia (Liocola) brevitarsis 不同地理种群的形态差异,重点探索新疆种群与其他地区种群间的形态差异,为植物保护和生产活动提供指导,丰富微进化理论。【方法】基于几何形态学的主成分分析(principal component analysis, PCA)和典型变量分析(canonical variate analysis, CVA)方法,对国内外30个地区共700头白星花金龟的鞘翅和前胸背板进行分析比较,研究白星花金龟不同地理种群的形态变异。【结果】白星花金龟前胸背板和鞘翅形态变异主成分分析中,新疆标本都明显聚在一起,但同时与新疆周边省份标本有部分重叠,与远离新疆省市有少部分重叠。新疆标本和南方地区种群标本明显分离。在各地区种群形态差异显著性检验中,基于马氏距离(Mahalanobis distance)和普氏距离(Procrustes distance)分析显示,新疆白星花金龟与远离新疆地区标本的前胸背板和鞘翅在马氏距离和普氏距离上均为显著性差异,而与其他地区标本的前胸背板和鞘翅的差异上,并非总是显著性差异。【结论】证实了前胸背板和鞘翅上的白斑可以作为白星花金龟地理种群变异的评价指标。就新疆白星花金龟而言,地理距离在一定程度上与形态距离相吻合。我们推测新疆白星花金龟是通过青海省北部以外的宁夏、内蒙古和甘肃三省入侵到新疆自治区,或者与上述三省该害虫的入侵来源一致。本研究所呈现的研究方式,在丰富微进化理论方面具有广阔的前景,且有望丰富分子生态地理学的研究内涵。  相似文献   

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