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1.
mtDNA diversity in rhesus monkeys reveals overestimates of divergence time and paraphyly with neighboring species 总被引:4,自引:0,他引:4
Reconstructions of the human-African great ape phylogeny by using
mitochondrial DNA (mtDNA) have been subject to considerable debate. One
confounding factor may be the lack of data on intraspecific variation. To
test this hypothesis, we examined the effect of intraspecific mtDNA
diversity on the phylogenetic reconstruction of another Plio- Pleistocene
radiation of higher primates, the fascicularis group of macaque (Macaca)
monkey species. Fifteen endonucleases were used to identify 10 haplotypes
of 40-47 restriction sites in M. mulatta, which were compared with similar
data for the other members of this species group. Interpopulational,
intraspecific mtDNA diversity was large (0.5%- 4.5%), and estimates of
divergence time and branching order incorporating this variation were
substantially different from those based on single representatives of each
species. We conclude that intraspecific mtDNA diversity is substantial in
at least some primate species. Consequently, without prior information on
the extent of genetic diversity within a particular species, intraspecific
variation must be assessed and accounted for when reconstructing primate
phylogenies. Further, we question the reliability of hominoid mtDNA
phylogenies, based as they are on one or a few representatives of each
species, in an already depauperate superfamily of primates.
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2.
M. V. Jato F. J. Rodríguez-Rajo M. J. Aira E. Tedeschini G. Frenguelli 《Aerobiologia》2013,29(2):263-278
The global climate change reported over recent years may prompt changes in the atmospheric pollen season (APS). The aim of this study is to evaluate the possible impact provoked by meteorological conditions variations at different seasons of the year or different geographical areas on APS. Alnus, Betula and Castanea atmospheric pollen seasons and trends during the last 17 years at Ourense and Vigo (Galicia—NW Spain) and Perugia (Italy) were analysed. Possible incidence of the meteorological trends observed in the different cities on the atmospheric pollen seasons and the chill and heat requirements were evaluated. Pollen data from Ourense, Vigo and Perugia (1995–2011) were used. Pollen sampling was performed using LANZONI VPPS 2000 volumetric traps (Hirst in Ann Appl Biol 36:257–265, 1952), placed on top of different buildings at a similar height from the ground. Several methods, dates and threshold temperatures for determining the chill and heat requirements needed to trigger flowering were tested. Different temporary order in the pollination sequence was observed between the three pollen types studied in the three sites. Alnus flowers few days in advance in Ourense respecting to Vigo and 1 month earlier than Perugia. The Betula flowering start date in Ourense and Vigo is almost simultaneous, taking place only 5 days in advance with respect to Perugia. Finally, scarce differences in the APS onset of Castanea were detected between the three cities. The variations observed among the two areas (Umbria, Italy and Galicia, Spain) in the onset of pollen season in the winter or spring flowering trees could be explained by differences in the thermal requirements needed for flowering as consequence of the climatic conditions recorded during the previous period to flowering. The length of the chilling and heat period as well as the thermal requirements obtained showed differences between geographical areas. The chill requirements accumulated were higher in Perugia than Ourense and Vigo. By contrary, the lowest heat accumulation was achieved in Perugia. The observed trends in the APS characteristics and the weather-related parameters were not homogeneous both in the pollen types and sites. The pollen index of Betula and Castanea pollen in Ourense shows a significant trend to increase. 相似文献
3.
Pollen data from the atmosphere of Vigo, NW Spain was collected using a Hirst type pollen trap over a seven-year period (1995–2001). A total of 56 different pollen types were identified, among which Urticaceae, Poaceae, Betula and Quercus represent the greatest risk for people suffering from allergic rhinitis (hay fever) or other allergic diseases. Although in the atmosphere of Vigo the presence of allergenic pollen is constant throughout the year, the months of March and April account for 40% of the annual total pollen count. Two main risk periods have been identified for asthma and allergies: (1) March – April, and (2) June – July, the latter is of greater importance due to high concentrations of Poaceae pollen. Correlation analysis with meteorological parameters demonstrates that rainfall, relative humidity, maximum temperature, sun hours and north-easterly winds are the main factors influencing the average daily pollen concentrations in the atmosphere. 相似文献
4.
This study shows the results of monitoring thepollen present in the atmosphere of the city ofLugo for three years (1999–2001) using a Hirstvolumetric trap (model Lanzoni VPPS-2000). During the three-year study, 61,381 pollengrains were counted. Poaceae represents 39.5%of the total pollen identified, Pinus12.3%, Quercus 8.7% and Betula8.4%. More than half of the total annualpollen was recorded in June and July. Itscorrelation was positive with temperature,hours of sun and wind speed, and negative withrainfall and relative humidity. The maximumvalues were recorded between 11 am and 8 pm,coinciding with the highest temperatures andlowest relative humidity. 相似文献
5.
The pollen count of the Platanus genus in the atmosphere of Santiago de Compostela (Galicia, Spain) was carried out from 1993 to 1998, with the pollen of this taxon representing 6% of total identified pollen. The principal pollination period (P.P.P.) was centred on the months of March and April, with an average duration of 23 days.During the study period we obtained negative correlations with precipitation and humidity and positive ones with temperature and hours of sunshine, with a confidence index of more than 90%. On the basis of the six-year study period, we also calculated the average accumulated temperature required to trigger the onset of flowering, which oscillated between 330 and 456 °C, with this result being confirmed for 1999 (437 °C). We also observed that the values of maximum pollen concentration of this taxon in the last 7 years (1993–1999), were obtained on days during the P.P.P. with maximum temperatures above 18 °C. The model of intradiurnal variation reflects, for the majority of years, a greater representation during the central hours of the day. 相似文献
6.
Francisco José González Minero Isabel Iglesias Victoria Jato Maria Jesús Aira Pilar Candau Julia Morales Carmen Tomas 《Aerobiologia》1998,14(2-3):117-129
A comparative study is presented of the pollen emissions of Urticaceae, Plantaginaceae and Poaceae, collected during 1995
with Hirst samplers (Burkard or Lanzoni) at five sites in western Spain: two Mediterranean sites located in the south (Huelva
and Seville) and three Atlantic sites in the north (Orense, Vigo and Santiago). The annual pollen of Poaceae and Plantaginaceae
collected in the Atlantic cities was found to be twice that in the Mediterranean sites, and the total amount of Urticaceae
was higher at sites with an urban environment and subject to sea influence (Vigo, Huelva and Seville). At all the sites, the
start of the main pollination periods (MPP) took place in the following order: Urticaceae, Plantaginaceae and Poaceae. It
was also observed that the MPP of these three pollen types began earlier in Huelva and Seville, where the mean temperatures
necessary for the beginning of pollen emissions are recorded very early. Regarding the variation in pollen concentrations
throughout the year, Urticaceae presented peaks of maximum concentration in March (Huelva, Seville, Vigo and Orense) and June
(Santiago); Plantaginaceae in March (south) and June (north); and Poaceae in May (south) and June–July (north). At northern
sites, pollen emissions of Urticaceae and Plantaginaceae continued throughout the summer, while in the south they decreased
considerably from May onwards. From the allergenic point of view, the indices of reactivity described for Urticaceae and Poaceae
were exceeded more often at northern sites, in particular at Vigo. The meteorological conditions associated with periods of
highest pollen emission of these three herbaceous types are a rise in mean temperature, light or absent rainfall, and abundant
sunshine. The statistical correlations between pollen emissions and meteorological factors were not well-defined, either for
the stations or for all the taxa, although they were clearer for the Atlantic cities and for Urticaceae. 相似文献
7.
Representativeness of point-wise phenological Betula data collected in different parts of Europe 总被引:1,自引:0,他引:1
8.
Matt Smith Jean Emberlin Alicja Stach Auli Rantio-Lehtimäki Eric Caulton Michel Thibaudon Charlotte Sindt Siegfried Jäger Regula Gehrig Giuseppe Frenguelli Victoria Jato F. Javier Rodríguez Rajo Purificación Alcázar Carmen Galán 《Aerobiologia》2009,25(4):321-332
Relationships between temporal variations in the North Atlantic Oscillation (NAO) and grass pollen counts at 13 sites in Europe, ranging from Córdoba in the south-west and Turku in the north-east, were studied in order to determine spatial differences in the amount of influence exerted by the NAO on the timing and magnitude of grass pollen seasons. There were a number of significant (P < 0.05) relationships between the NAO and start dates of the grass pollen season at the 13 pollen-monitoring sites. The strongest associations were generally recorded near to the Atlantic coast. Several significant correlations also existed between winter averages of the NAO and grass pollen season severity. Traditional methods for predicting the start or magnitude of grass pollen seasons have centred on the use of local meteorological observations, but this study has shown the importance of considering large-scale patterns of climate variability like the NAO. 相似文献
9.
V. Jato F. J. Rodríguez-Rajo M. C. Seijo M. J. Aira 《International journal of biometeorology》2009,53(4):333-344
Airborne Poaceae pollen counts are greatly influenced by weather-related parameters, but may also be governed by other factors.
Poaceae pollen is responsible for most allergic reactions in the pollen-sensitive population of Galicia (Spain), and it is
therefore essential to determine the risk posed by airborne pollen counts. The global climate change recorded over recent
years may prompt changes in the atmospheric pollen season (APS). This survey used airborne Poaceae pollen data recorded for
four Galician cities since 1993, in order to characterise the APS and note any trends in its onset, length and severity. Pollen
sampling was performed using Hirst-type volumetric traps; data were subjected to Spearman’s correlation test and regression
models, in order to detect possible correlations between different parameters and trends. The APS was calculated using ten
different methods, in order to assess the influence of each on survey results. Finally, trends detected for the major weather-related
parameters influencing pollen counts over the study period were compared with those recorded over the last 30 years. All four
cities displayed a trend towards lower annual total Poaceae pollen counts, lower peak values and a smaller number of days
on which counts exceeded 30, 50 and 100 pollen grains/m3. Moreover, the survey noted a trend towards delayed onset and shorter duration of the APS, although differences were observed
depending on the criteria used to define the first and the last day of the APS. 相似文献
10.