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101.
The contemporary genetic pattern of European moose is shaped by postglacial recolonization,bottlenecks, and the geographical barrier of the Baltic Sea 下载免费PDF全文
Magdalena Niedziałkowska Kris J. Hundertmark Bogumiła Jędrzejewska Vadim E. Sidorovich Hanna Zalewska Rauno Veeroja Erling J. Solberg Sauli Laaksonen Håkan Sand Vyacheslav A. Solovyev Andrey Sagaydak Juha Tiainen Rimvydas Juškaitis Gundega Done Vadim A. Borodulin Evgenii A. Tulandin Krzysztof Niedziałkowski 《Biological journal of the Linnean Society. Linnean Society of London》2016,117(4):879-894
To investigate genetic diversity and the population structure of the European moose (Alces alces), we analyzed 14 microsatellite loci for 694 samples collected across 16 localities. The highest genetic diversity was detected in Belarus and Russia and the lowest was found in Scandinavia. Two major genetic clusters existed, Scandinavian and continental, and some further spatial structure was detected. There was high concordance between the spatial distribution of microsatellite clusters analyzed in the present study and previously recognized mitochondrial DNA clades of moose. The split of genetic lineages calculated using approximate Bayesian computation (ABC) occurred at the beginning of the Last Glacial Maximum: approximately 29 000 and 28 000 years BP. A range‐wide bottleneck detected by ABC took place 1800–1200 years BP, although a more recent decline in moose numbers was also documented in the 18th to early 20th Century. Genetic differentiation in European moose increased with geographical distance, and the Baltic Sea appeared to be a barrier to gene flow. We conclude that isolation in different glacial refugia, postglacial colonization, and declines of range and numbers in Holocene shaped the present pattern of genetic diversity of European moose. Based on genetic divergence and a lack of apparent gene flow, the contemporary Scandinavian and continental subpopulations should be treated as separate management units. 相似文献
102.
The novel neuronal ceroid lipofuscinosis gene MFSD8 encodes a putative lysosomal transporter 下载免费PDF全文
Siintola E Topcu M Aula N Lohi H Minassian BA Paterson AD Liu XQ Wilson C Lahtinen U Anttonen AK Lehesjoki AE 《American journal of human genetics》2007,81(1):136-146
The late-infantile-onset forms are the most genetically heterogeneous group among the autosomal recessively inherited neurodegenerative disorders, the neuronal ceroid lipofuscinoses (NCLs). The Turkish variant was initially considered to be a distinct genetic entity, with clinical presentation similar to that of other forms of late-infantile-onset NCL (LINCL), including age at onset from 2 to 7 years, epileptic seizures, psychomotor deterioration, myoclonus, loss of vision, and premature death. However, Turkish variant LINCL was recently found to be genetically heterogeneous, because mutations in two genes, CLN6 and CLN8, were identified to underlie the disease phenotype in a subset of patients. After a genomewide scan with single-nucleotide-polymorphism markers and homozygosity mapping in nine Turkish families and one Indian family, not linked to any of the known NCL loci, we mapped a novel variant LINCL locus to chromosome 4q28.1-q28.2 in five families. We identified six different mutations in the MFSD8 gene (previously denoted "MGC33302"), which encodes a novel polytopic 518-amino acid membrane protein that belongs to the major facilitator superfamily of transporter proteins. MFSD8 is expressed ubiquitously, with several alternatively spliced variants. Like the majority of the previously identified NCL proteins, MFSD8 localizes mainly to the lysosomal compartment. However, the function of MFSD8 remains to be elucidated. Analysis of the genome-scan data suggests the existence of at least three more genes in the remaining five families, further corroborating the great genetic heterogeneity of LINCLs. 相似文献
103.
Rauno Mäntyjärvi Henry Karjalainen Mariitta Laaksonen 《Cancer immunology, immunotherapy : CII》1984,17(1):28-32
Summary Syngeneic or allogeneic cells transformed by BK virus (BKV) were used to immunize C57BL/6J mice. After in vitro stimulation, lymphocytes prepared from the spleens of immunized mice were used in in vitro cytotoxicity tests. The results of these tests revealed the presence of a cell surface antigen, presumably corresponding to the viral transplantation antigen, common to all tested BKV- and SV40-transformed cell lines of C57BL/6J origin. An allogeneic cell line transformed by BKV also contained the same antigen. Immunization, i.e., in vivo priming, did not require syngeneic transformed cells, whereas cytolysis was only observed when the virus-specific antigen on target cells was associated with the same H2 haplotype as was expressed by effector cells. An additional unidentified antigen was shared by some of the BKV-transformed cell lines and cell lines transformed by simian adenovirus SA7. 相似文献
104.
We examined the reactions of captive wild great tits to novelunpalatable prey with (1) a traditional aposematic signal (blackand yellow) (2) a novel signal (light pink), and (3) a controlsignal (brown). Prey were offered either singly or in groupsto see whether novel signals with fewer possibilities for synergisticbenefits are more dependent on grouping than are the traditionalsignals. Indeed, responses of birds toward unpalatable preydepended significantly on spatial distribution of prey (groupingversus solitary) and the type of the signal. Birds avoided morethe traditional black and yellow signals than novel pink signalsin both experimental set ups, but both of these prey items survivedbetter in aggregation than solitarily. The success of traditionalsignals may demonstrate the importance of synergistic selectionacross species in the evolution of warning coloration (i.e.,Müllerian mimicry). Unpalatable prey individuals benefitstrongly from using similar color patterns. Our results suggestthat aggregation may be important for the evolution of novelsignals in particular, even if a synergistic selection componentis also present 相似文献
105.
Rauno V. Alatalo 《Oecologia》1980,45(2):190-196
Summary The five most abundant species were included in a year-round study with respect to six foraging niche dimensions. Approximately full multidimensional utilization functions were used for niche metrics. During summer foraging overlaps were invariably high, but in other seasons periodically lower. Foraging site breadth was lower in winter, when fewer sites are profitable for foraging than in summer. Feeding posture versatility, by contrast, was highest in winter. Seasonal foraging shifts were very prominent, as great in fact as between-species differences. Often seasonal trends were parallel in different species. Niche axes of macrohabitat-type (e.g. tree) were more open for foraging variation and axes of microhabitat-type (tree part) more rigid. Among the resident species seasonal variation in foraging was greatest in Regulus regulus and Parus cristatus, whereas the foraging behaviour was more stable for P. montanus (an abundant species with broad niche), perhaps owing to greater intraspecific competition. In these northern forests foliage-gleaners must be versatile generalists to cope with the unpredictable resources, and thus they overlap broadly in their general resource niches which are determined by their genetically fixed cost and benefit relations to each resource type. Anyhow, presumably during periodical food shortage, the actual resource uses adjusted by resource availability and competition may overlap narrowly. 相似文献
106.
Kokko Hanna; Lindstrom Jan; Alatalo Rauno V.; Rintamaki Pekka T. 《Behavioral ecology》1998,9(4):376-383
The importance of a central territory position as a determinantof male mating success in lekking species has been debated.The process by which a male can obtain a central territory hasbeen especially lacking a quantitative analysis. We presenta stochastic queuing model describing territory succession towardthe lek center and apply it to a 8-year sequence of territorycentrality measures on a black grouse Tetrao tetrix lek. Thelek shows a value of intermediate queue discipline, which deviatessignificantly both from strict orderly queuing and from randomranking of males. Thus, high-ranking males are partly able tomaintain their superior position over years, but queue-jumpingis not excluded; especially because highly succesful males donot attempt to change their territory position toward the lekcenter. As a result of stochastic queuing, a central territoryindicates an older than average male, as well as a male witha history of high fighting rates. These results are consistentwith the hypotheses that territory position is an honest signalof male quality and that the long-term fighting effort and survivalrequired to acquire a central territory may increase the reliabilityof the signal over that of short-term display effort. The impartialqueue discipline, however, also leaves room for other male characteristicsto play a role in determining individual mating success. 相似文献
107.
Blood parasites and male fitness in the pied flycatcher 总被引:2,自引:0,他引:2
In vertebrates the effect of parasites on host ecology has almost been ignored. Recently the view that well-adapted parasites
do not harm their hosts has been challenged and there is growing evidence that parasites do have a present-day effect on a
great variety of host fitness components. The pied flycatcher is a small migratory passcrine bird. Any decrease in condition
caused by disease should affect its ability to cope with physical demands of migration. Here we examine whether blood parasites
have any effect on male arrival time. Males infected with Trypanosoma arrived on average 2 days later than males with no Trypanosoma infection. Infected males also had shorted tails and tended to have shorter wings. By contrast, there was no difference in
male arrival time between males infected with Haemoproteus and healthy males. It seems that Trypanosoma infection lowered male condition and consequently the ability to moult and migrate. The difference in length of feathers
may have generated the difference in arrival times. Early arrival is highly important for males, since only the first males
become polygynous and breeding prospects deteriorate rapidly with any delay in egg laying. Estimated reduction in breeding
success for infected males was about 20%. 相似文献
108.
Relationships between female size and fecundity, egg viability and embryonal development were studied in Neoriprion sertifer. Sawfly females, reared from the 1st instar larvae on Scots pine needles heavily affected by industrial pollutants or on relatively unpolluted needles, were induced to lay eggs parthenogenetically in the field in Finland. Females reared on polluted needles were smaller and oviposited an average of 68.8 eggs, and those reared on unpolluted needles 79.4 eggs per female. However, the higher egg viability in the former group masked the effect of reduced female size. This compensation was primarily related to the size of the females, larger individuals producing relatively fewer viable eggs in both groups. 相似文献
109.
Polyterritoriality, the occupation of two spatially separateterritories by male birds, has been suggested to enable malesto conceal their pairing status. The idea that males deceivefemales has recently been questioned with arguments that femaleswould easily be able to detect polyterritorial males and thatthey mate in the second territories because better breedingoptions are not available close by. We arranged for pied flycatcher(ficedula hypoleuca) females a choice between neighboring unmatedand already-mated males. Females were unable to discriminateagainst already-mated males, even though their breeding successthereby would have been increased. These results allow rejectionof any polygyny models that assume females use male pairingstatus as a criterion for mate choice. Females would reducethe probability of mating polygynously by choosing dull, yearlingmales with high song rate, even though in most cases it is difficultto differentiate already-mated and unmated males. In fact, femalesdid not prefer colorful males, opposing a general pattern foundin other bird species. However, females did not specificallyprefer dull males nor did they respond to slight differencesin song rates. The seemingly nonadaptive, imperfect female behaviorsuggests that the evolution of female selectivity is constrained,allowing deception by males to be successful in the evolutionaryarms race between the sexes. [Behav Ecol 1990,-1:171177] 相似文献
110.
Characterization of ozonated vegetable oils by spectroscopic and chromatographic methods 总被引:1,自引:0,他引:1
Sadowska J Johansson B Johannessen E Friman R Broniarz-Press L Rosenholm JB 《Chemistry and physics of lipids》2008,151(2):85-91
In this work the effect of ozonation on olive oil, soybean oil, oleic-, linoleic- and linolenic acid was studied. The effects of ozonation time on the oils and acids were analyzed by 1H, 13C NMR. Further, the peroxide- and acid values, the viscosity and the molar mass were determined for pure and ozonated oils. The fatty chains in both ozonated oils showed a gradual decrease of unsaturation with the gradual increase of ozonation time. Reaction products were identified according to Criegee mechanism. The major product in the early stage of the reaction was ozonide. The disappearance of unsaturation and formation of ozonide was almost equal. Ozonation increased the peroxide and acid values for both oils, the increase being higher for soybean oil. After long ozonation times higher molar mass species, as well as low molar mass species were observed. These are interpreted as oligomeric ozonides and cross-ozonides, respectively. 相似文献