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1.
Seven microsatellite loci were isolated and characterized from the red‐capped robin Petroica goodenovii, using nonradioactive polymerase chain reaction (PCR)‐based techniques to screen an enriched genomic library. Five loci showed no evidence of null alleles and were variable [mean heterozygosity (HE) = 0.440, mean number of alleles = 8]. Cross‐amplification using primers for microsatellites in Phylloscopus occipitalis and Emberiza schoeniclus yielded another two polymorphic loci. The combined set of five red‐capped robin and two cross‐amplified loci are suitable for paternity assignment (exclusion probability for seven unlinked loci = 0.9760).  相似文献   

2.
The New Zealand robin (Petroica australis), tomtit (P. macrocephala), and Chatham Island black robin (P. traversi) are members of the Petroicidae family of Australo-Papuan robins, found throughout Australasia and the western Pacific. In the nearly 200 years since the New Zealand members of Petroicidae were first described, the division of species, subspecies, and even genera has undergone many changes. In this study, we investigate whether molecular phylogenies based on mitochondrial DNA sequences support current taxonomic classifications based on morphology. Petroica traversi, P. australis, and P. macrocephala form distinct clades in phylogenetic trees constructed from Cytochrome b and control region sequences, however the position of the black robin is at odds with the morphological and behavioral data. The black robin does not appear to be a derivative of the New Zealand robin, instead it groups strongly with the tomtit, indicating that lineage sorting and/or introgressive hybridization may have occurred. There is some evidence to support the hypothesis that two invasions of Petroica from Australia have occurred, however additional data from Australian Petroica taxa are required to confirm this. Control region sequences confirm a deep split between the North and South Island P. australis lineages, but suggest a recent radiation of P. macrocephala.  相似文献   

3.
四种斑腿蝗科昆虫染色体带型的比较   总被引:7,自引:1,他引:7  
马恩波  郭亚平 《昆虫学报》2001,44(3):268-275
应用染色体C带及银染核仁组成区定位分析方法对斑腿蝗科4种昆虫,即小蹦蝗属2种;峨眉小蹦蝗Pedopodisma emeiensis和秦岭小蹦蝗P.tsinlingensis;无翅蝗属2种;小无翅蝗Zubovskiaparvula和柯氏无翅蝗Z.koeppeni进行了研究,结果表明:4种蝗虫染色体数目(2n♂=21,XO)一致,小蹦蝗属M8染色体上具有端带;无翅蝗属X染色体具有特殊带纹,银染核仁组成区定位在两属各有特点,小蹦蝗属位于第8号染色体端部区域;无翅蝗属位于X染色体端部区域,除上述属内共性之外,各物种C带带纹又存在明显差异,其中峨眉小蹦蝗带型极为特殊。文中还对上述4种蝗虫带型结构特征及其进化意义作了讨论。  相似文献   

4.
Hybridisation between an endangered species and a more common species can facilitate population decline and extinction of the endangered species due to wasted reproductive effort, outbreeding depression and/or swamping of alleles due to widespread or complete admixture. The Chatham Island black robin (Petroica traversi) is an endangered songbird species, which was reduced to only five individuals in 1980. Intensive cross-fostering, whereby black robin offspring were placed into nests of the closely related Chatham Island tomtit (Petroica macrocephala chathamensis) to increase reproductive output, contributed to the rapid recovery of the species within 10 years. Several hybridisation events occurred and although those hybrids were successfully eliminated from the population, concerns remained for the possibility of introgression between the two species that may have gone unnoticed. In this study, we genotyped seven microsatellite loci in both species from the two islands where they coexist, to assess the level of hybridisation and the extent of introgression between the two species. The two species shared no alleles at five of the seven loci genotyped, and cluster analysis, AMOVA and admixture analysis of a total of 174 black robins and 78 Chatham Island tomtits showed no evidence of hybridisation or introgression on either of the two islands where they co-exist. As a result, there is no evidence that black robins are currently in any danger of population decline or extinction through hybridisation with tomtits, although small population size and skewed sex ratio, particularly in the smaller of the two populations, may facilitate future hybridisation events.  相似文献   

5.
Boroń A 《Genetica》2003,119(1):51-55
The chromosomal complement of Cobitis taenia was analysed by replication banding techniques to determine whether there were specific patterns that could allow distinction of the different chromosomes. The diploid chromosome number of 2n = 48 is diagnostic of this species. In vivo 5-bromodeoxyuridine (5-BrdU) incorporation induced highly reproducible replication bands. Most of the chromosome pairs were distinguishable on the base of their banding patterns. The karyotype, consisting of five pairs of metacentrics, nine pairs of submetacentrics and 10 pairs of subtelocentrics and acrocentrics, was confirmed. C-banding and replication banding patterns were compared, and heterochromatin was both early and later replicating. C-positive heterochromatin in centromeric regions was mainly early replicating, but that located in pericentromeric regions was late replicating. Most of the late-replicating regions found interstitially were C-band negative. The results obtained so far for combined chromosomal staining methods of C. taenia and other Cobitis fish species are discussed.  相似文献   

6.
Prometaphase lymphocyte chromosomes from eight adult argentinian Alouatta caraya females were characterized using sequential G-C banding techniques, Ag-NOR bands and bands obtained with the restriction enzymes Hae III, Eco RI, Alu I and Sau 3A. The cytogenetic analysis showed 2n = 52, with four, five, or six NOR chromosomes. Digestion with Hae III and Eco RI produced G-like-bands. Centromere regions and two interstitial C-bands (in chromosomes number 16 and 21) showed intraindividual or interindividual heterochromatic polymorphisms. Alu I digestion produced C-like bands with gaps in the centromere regions, and Sau 3A produced C-like bands. The karyotypes and banding patterns of A. caraya, A. palliata, A. belzebul, and A. seniculus are compared, based on whole chromosome and whole arm homeologies. © 1994 Wiley-Liss, Inc.  相似文献   

7.
Abstract

The extent of darkening of melanin‐based plumages in birds has previously been linked with increasing aggressive encounters between individuals. The North Island robin (Petroica longipes) is a territorial New Zealand endemic passerine that displays delayed plumage maturation (darkening of the plumage with age). Aggressive boundary interactions in the robin are relatively common during the breeding season, when territories are protected and juveniles are dispersing. This study tests the hypothesis of aggression‐mediated plumage darkening in a population of North Island robins by examining if males and older (darker) birds are either (1) involved in a higher number of aggressive interactions, or (2) are more often the aggressor than females and younger birds. When sex and age are accounted for, darker individuals will be either (3) involved in a higher number of interactions or (4) more often the aggressor in encounters with other individuals. Data were collected by scoring the plumage darkness of 32 individuals in the field, and observing (1) interaction behaviours, and (2) age and sex of the birds involved in each interaction. The results show no support for any aggression‐mediated plumage darkness in the robin; males and older birds were not involved in more aggressive interactions, and were not more often the aggressor; and neither the frequency of interactions or the number of aggressive interactions were correlated with a darker plumage. Other more complex mechanisms may explain delayed plumage darkness in the North Island robin.  相似文献   

8.
Summary Short incubation of heparinized human leukemic bone-marrow cells in phosphate buffered saline containing colcemid and overnight chilling of fixed cells yields metaphases with elongated and well-spread chromosomes. This technique enables us to do trypsin-Giemsa banding of chromosomes obtained from leukemic marrow cells otherwise difficult to band.  相似文献   

9.
The chromosomes of the European eel Anguilla anguilla have been analyzed with a replication banding technique from lymphocyte cultures treated with 5-BrdU. This technique allows us to identify with high resolution the individual chromosome pairs and to differentiate classes of chromatin by the order of replication. The replication banding obtained on the chromosomes of European eel can be related with the structural bands described in this species.  相似文献   

10.
The two species of the genusBrimeura (Liliaceae),B. amethystina andB. fastigiata, show a strikingly disjunct geographical distribution. Both species have a bimodal chromosome complement, 2n = 28, which includes 10 large (L) and 18 small (S) chromosomes. Most of the L-chromosomes possess heterochromatic segments which show enhanced quinacrine fluorescence. The resulting banding patterns are species-specific. Two triploid plants have been found inB. fastigiata.  相似文献   

11.
Fluorochrome chromosome banding is applied for the first time to 15 samples of five cultivatedCapsicum species, all with 2n = 24, and allows a detailed analysis of the karyotypes (Tables 2–3, Fig. 8). Banding patterns differ between cytotypes, species and groups, reflecting the dynamics of chromosomal differentiation and evolutionary divergence. Taxa have from 1 to 4 NOR-bearing satellited chromosome pairs and exhibit increasing numbers of terminal (rarely intercalary and indistinct centromeric) heterochromatic fluorescent bands. Amounts of heterochromatin (expressed in % of karyotype length) increase from the group withC. annuum (1.80–2.88),C. chinense (3.91–5.52), andC. frutescens (5.55) toC. baccatum (7.30–7.56), and finally toC. pubescens (18.95). In all taxa CMA+DAPI—(GC-rich) constitutive heterochromatin dominates, onlyC. pubescens has an additional CMAo DAPI+ (AT-rich) band. The fluorochrome bands generally (but not completely) correspond to the Giemsa C-bands. Structural heterozygosity can be demonstrated but is not prominent. The independent origin of at least three evolutionary lines leading to the cultivated taxa ofCapsicum is supported.Chromosome studies inCapsicum (Solanaceae), V. For the fourth part seeMoscone & al. 1995.  相似文献   

12.
Abstract Giemsa C‐banding was applied to the chromosome complements of six diploid species belonging to six genera in Chrysanthemum sensu lato (Anthemideae) distributed in Egypt. Four types of C‐banding distribution were observed in the taxa as follows: (i) negative C‐banding in Anacyclus monanthos (L.) Thell.; (ii) all bands in terminal regions in Achillea fragrantissima (Forssk.) Sch. Bip, which showed 32 bands on 18 chromosomes; (iii) all eight bands at centromeric regions on eight chromosomes in Matricaria recutita L.; and (iv) bands at terminal and centromeric regions in Brocchia cinerea Vis. (12 terminal and six centromeric bands on 12 chromosomes), Cotula barbata DC. (four terminal, six centromeric, and eight short arm bands on 16 chromosomes), and Glebionis coronaria (L.) Cass. ex Spach. (eight terminal on the short arms and four large bands in centromeric regions on 12 chromosomes).  相似文献   

13.
Chlorophyll-nutrient relationships in North Island lakes (New Zealand)   总被引:3,自引:2,他引:1  
A model for the prediction of chlorophyll a in the near surface waters (1 m) of North Island lakes was developed using data from the literature and our own study of 12 North Island lakes. Annual geometric mean concentrations of chlorophyll a, total nitrogen and total phosphorus were used since no distinct growing season was discernable. Annual mean ratios of total nitrogen to total phosphorus in the near surface waters ranged between 10 and 59 (by weight). Strong correlations were obtained between log-transformed values of chlorophyll a and total nitrogen (r2 = 0.53, n = 16), chlorophyll a and total phosphorus (r2 = 0.71, n = 21), and between total nitrogen and total phosphorus (r2 = 0.69, n = 16). However, after correcting for the high interdependency between total nitrogen and total phosphorus, only total phosphorus was found to be important in predicting chlorophyll concentrations. Much of the variance in the chlorophyll-phosphorus relation was attributable to differences in mean lake depth. Lakes with mean depths less than 11 m had significantly more chlorophyll a per unit of total phosphorus ( = 0.54 µg · µg–1, SE = 0.05, n = 6) than lakes of greater mean depth ( = 0.17 µg · µg–1, SE = 0.02, n = 14). When the effect of mean depth was taken into account, 89% of the variance in chlorophyll a was explained compared with 71% for the simple linear regression on total phosphorus alone.  相似文献   

14.
The karyotype of the common ice plant Mesembryanthemum crystallinum L. (Aizoaceae) was studied using Chromomycin A3 (CMA)/4′,6-diamidino-2-phenylindole (DAPI) staining, fluorescence in situ hybridization with 5S and 18S–5.8S–25S rDNA probes, DAPI/C-banding and immunodetection of 5-methylcytosine. A single bright CMA-band was revealed on the satellite chromosome, whose location was coincided with a position of a site of 18S–5.8S–25S rRNA genes. A site of 5S rRNA genes was observed on one of the other chromosomes. Relatively large DAPI/C-bands were mainly localized in the pericentromeric regions of the chromosomes. DAPI/C-banding patterns allowed us to identify all the chromosomes in the karyotype of M. crystallinum. The methylation of euchromatic chromosome regions was weaker as compared with heterochromatic DAPI/C-bands, which were hypermethylated. The obtained results may provide opportunities for investigating, at the chromosomal level, the genomic changes occurring in M. crystallinum either under salinization or under the action of other stress factors.  相似文献   

15.
In this study, we analyse New World coral snakes in a phylogenetic framework based upon an increased molecular data set, including novel sequences for the only two sympatric species known from an island (Trinidad, West Indies). Their presence in Trinidad and absence in Tobago offers a unique system to study the phylogeography of the region. We assess the tempo and mode of colonisation of Micrurus on the island, in addition to discussing the phylogenetic relationships for the genus Micrurus concerning two phenotypic traits, body and tail banding patterns. These relationships are analysed for the first time on statistical coalescent phylogeographic discrete ancestral reconstruction. We find a robust phylogenetic component in these characteristics, where strongly supported clades are recovered: prior to the onset of the Early Miocene, a triadal and tricolour tail clade composed of species from South America, and a second clade dating to the Middle‐Late‐ Miocene with monadal and bicolour tails widely distributed from North to South America. The divergence between clades dates to the Oligocene and suggests an ancient pre‐isthmus divergence supporting the arrival of the triadal clade into South America, before the connection between Central and South America was established. We find the two coral snakes present in the West Indies, M. diutius and M. circinalis, belong to the triadal and monadal clades, respectively. Guyana and Trinidad Micrurus diutius share the same haplotypes suggesting a Late Pleistocene–Holocene vicariance when sea level rises separated Trinidad from the mainland. A second lineage of diutius‐like snakes is present in Guyana and is confirmed as M. lemniscatus which is assigned as a voucher and restricts the type locality for M. lemniscatus.  相似文献   

16.
The karyotypes of four South American species of Cestrum (C. capsulare,C. corymbosum,C. laevigatum and C. megalophylum) were studied using conventional staining, C-CMA/DAPI chromosome banding and FISH with 45S and 5S rDNA probes. The karyotypes showed a chromosome number of 2n = 2x = 16, with metacentric chromosomes, except for the eighth submeta- to acrocentric pair. Several types of heterochromatin were detected, which varied in size, number, distribution and base composition. The C-CMA(+) bands and 45S rDNA were located predominantly in terminal regions. The C-CMA (+) /DAPI (+) bands appeared in interstitial and terminal regions, and the C-DAPI (+) bands were found in all chromosome regions. The 5S rDNA sites were observed on the long arm of pair 8 in all species except C. capsulare, where they were found in the paracentromeric region of the long arm of pair 4. The differences in band patterns among the species studied here, along with data from other nine species reported in the literature, suggest that the bands are dispersed in an equilocal and non-equilocal manner and that structural rearrangements can be responsible for internal karyotype diversification. However, it is important to point out that the structural changes involving repetitive segments did not culminate in substantial changes in the general karyotype structure concerning chromosome size and morphology.  相似文献   

17.
Knowledge of threatened species’ distributions is essential for effective conservation decision‐making. Species distribution models (SDMs) are widely used to map species’ geographic ranges, identify new areas of suitable habitat and guide field surveys. In New South Wales (NSW), Australia, there are grave doubts about whether populations of the critically endangered long‐footed potoroo (Potorous longipes) remain extant, and identification of occupied sites is a high priority for its conservation. We used an SDM (Maxent) to identify regions in NSW that may have suitable habitat for the potoroo. The SDM was built with seven climate layers and had strong predictive performance (cross‐validated AUC = 0.94). We then combined this information on habitat suitability with vegetation and topography, to identify 58 survey sites across NSW. From April 2016 to May 2017, we undertook six field trips deploying six to eight cameras at each site for 52–63 days, resulting in 25 120 camera trap nights. A total of 215 759 images captured 43 native and feral animal species, but no long‐footed potoroos. Following the survey, newly available, independent presence and absence data were used to validate our model. A Kruskal–Wallis H test indicated that habitat suitability values were significantly higher at presence locations than absence locations (H = 58.66, d.f. = 1, P < 0.001). Finally, we refitted the Maxent model with the new data and identified additional regions that future surveys could explore. We conclude, however, that if the long‐footed potoroo remains extant in NSW, it is extremely rare.  相似文献   

18.
The karyotypes of five Brazilian species of Echinodorus; E. bolivianus, E. grandiflorus, E. longipetalus, E. macrophyllus and E. tenellus (Alismataceae); were studied using C-banding, CMA3/DAPI banding and fluorescence in situ hybridization with a 45S rDNA probe. There were few differences in the G-C rich regions of the five species, but marked differences were seen in the number and position of C-bands, A-T rich regions and 45S rDNA sites. Overall, these characteristics were species-specific, with the exception of E. bolivianus and E. tenellus, which were highly similar in all of the karyotypic characteristics studied.  相似文献   

19.
Abstract

We conducted acoustic and behavioural observations on wild New Zealand North Island kaka (Nestor meridionalis septentrionalis) to assess the behavioural context of their most common calls. We distinguished several call types by ear in the field and then quantitatively evaluated our call type classifications using spectrographic analyses. Next, we established the behavioural context of each call type during 500 h of field observations. We observed five distinctive call types that were clearly segregated in subsequent spectrographic analyses. Behavioural observations showed that each call type was generally associated with particular behaviours used by birds separated by different distances. Some call types were used by distantly‐separated solitary birds that were foraging or preening, while others were used mostly during copulation. Overall results indicate that kaka have a range of distinctive call‐types for communication under different spatial and social circumstances.  相似文献   

20.
Prospero is a Mediterranean autumn-flowering genus ofHyacinthaceae commonly classified inScilla asS. autumnalis andS. obtusifolia. Extensive dysploid and polyploid variation has been reported. In the present study 77 diploid accessions from the western to the eastern part of the area of distribution, the major part being from continental Greece and Crete, have been analysed for karyotype structure and, in part, for genome size. Methods employed were acetocarmine staining, Giemsa C-banding, fluorochrome staining mainly with chromomycin A3/DAPI, silver impregnation, and Feulgen densitometry. Banded idiograms were established with a computer assisted karyotype analysis procedure. Chromosome numbers were 2n = 8 inP. obtusifolium, and 2n = 12 and 14 inP. autumnale s. l. Dispensable euchromatic chromosome segments and different types of B chromosomes occurred. Among the cytotypes with 2n = 14 two karyotypes from Turkey differed from each other and from the rest in form, position of the nucleolar constriction, and in genome size. The remaining accessions were similar in karyotype shape but three levels of genome size could be discerned, the highest (1C = 7.50 pg) being found on the Iberian Peninsula, an intermediate one on Corsica and Malta, and the lowest (4.27 pg) in the Aegean. The karyotype with 2n = 12 had an intermediate genome size, and that ofP. obtusifolium a relatively low one. Heterochromatin amount was generally low, but some karyotypes showed characteristic banding patterns. The relationship between the chromosome complements with 2n = 14, 12 and 8 is discussed on the basis of idiograms and DNA amounts.The authors respectfully dedicate this papers to emer. o. Prof. Dr.Elisabeth Tschermak-Woess on the occasion of her 80th birthday.  相似文献   

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