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1.
The patterns of molt in the chiffchaffs of the nominotypical subspecies from central Europe and eastern European subspecies from the Ladoga region are compared with that of the Siberian subspecies from the lower Ob region. The onset dates of postjuvenile molt in the Siberian subspecies are controlled endogenously, while in the nominative and, probably, eastern European subspecies they are under photoperiodic control. The molt of chiffchaffs from central Europe is no less complete than in birds from the Ladoga region and more complete than in Siberian birds. The individual duration of molt is the shortest in Siberian birds and the longest in central European birds, being intermediate in birds from the Ladoga region. Differences in the pattern of postnuptial molt between chiffchaffs from the Ladoga and Ob regions concern its duration and completeness. The completeness of molt proved to be reduced in half of examined birds from the Ladoga region and in some birds from the Ob region. The duration of complete molt in birds from the Ob region is smaller (40 days vs. 60 days in birds from the Ladoga region) at a longer daylight period, which is evidence for a higher rate of feather growth. The completeness and timing of prenuptial molt do not differ between the subspecies.  相似文献   

2.
The allozyme analysis of six local populations of Pinus mugo Turra and six populations of P. sylvestris L. in the Ukrainian Carpathians, Swiss Alps, and Schwarzwald has shown a higher polymorphism and greater interpopulation differentiation of the Carpathian group of P. mugo populations compared to the Alpine group (Nei’s genetic distance DN 78 at the level of geographic population group is −0.023). A genetic differentiation of DN 78 = 0.049 between these populations, which are isolated by a distance of more than 1000 km, has been found. This confirms the existence of the subspecies P. mugo ssp. mugo and P. mugo ssp. uncinata in the Carpathians and Alps, respectively. The hypothesis is put forward that the former subspecies has been formed in the Balkans and the latter, in the Pyreneans. It has been demonstrated that regional populations and geographic groups of P. sylvestris are less differentiated than those of P. mugo.  相似文献   

3.
The polymorphism of shell banding pattern has been studied in Crimean populations of the land snail H. albescens. The results show that snails from different regions of the Crimea are characterized by specific types of shell polymorphism, the differences between them concerning mainly the number of observed shell morphs rather than their occurrence frequency. In particular, the proportion of snails with darkly colored shells increases in relatively cool habitats. However, among the microevolutionary processes determining the type and degree of polymorphism in H. albescens populations, a major role is also played by stochastic genetic phenomena, because the species exists in semi-isolated colonies with low effective abundance and high risk of local extinction.  相似文献   

4.
Allozyme analysis of 18 Pinus sylvestris L. populations from seven landscape-geographic groups has been performed in the Greater Caucasus, Crimea, and Russian Plain. The results show that populations of the Mt. Elbrus region (isolated by high mountain ridges) are characterized by lower polymorphism and most distinct differentiation (at the level of geographic race) from other populations, which are differentiated from each other at the level of geographic groups. Genetic gradients (boundaries) between populations reach a maximum on transects across the Greater Caucasus Range, and Transcaucasian populations are more similar to populations of the Russian Plain, compared to North Caucasian populations, which confirms the hypothesis of ancestral connections between their gene pools.  相似文献   

5.
In the nominotypical subspecies of the citrine wagtail, M. c. citreola Pall., the density of nesting pairs in the northern part of its range in the central Yamal Peninsula reaches a peak in the moss-lichen tundra subzone, while similar biotopes (moist herb-moss willow scrub) are also present in the forest-tundra and shrub tundras. It is suggested that one of the causes of such an unusual distribution is that the birds feed on tipulid larvae, which dominate by biomass among invertebrates in moist moss-lichen tundras. The species is capable of successful existence in the northern Subarctic because of the brevity of its post-nesting period, determined by the endogenous control of the age at the onset of postjuvenal molt, rapid molting during the polar day, partial postnuptial molt, and early development of the migratory state, which provides for early departure.  相似文献   

6.
On the basis of abundant fossil and subfossil bone remains, the ecological and faunal role of the narrow-skulled vole in zonal rodent communities of northern Eurasia is analyzed over the period from the Late Pleistocene to the present time. Special attention is given to the correlated dynamics of relative abundance of Microtus gregalis and other rodent species in the course of transition from one zonal type to another and to specific features of this correlation in the southern, middle, and northern parts of the species range. It is shown that distinctive dimensional and morphotypic features of the two currently existing subspecies, Microtus gregalis major Ogn. and M. g. gregalis Pall., are the product of concordant development of the species and environmental conditions in the past 3000–4000 years (transition from the Holocene optimum to the present-day climate and state of the natural environment). Published in Russian in Ekologiya, 2007, Vol. 38, No. 2, pp. 117–123. The article was translated by the authors.  相似文献   

7.
The impact of the nuclear polyhedrosis virus on the population dynamics of the gypsy moth Lymantria dispar L. has been studied. The results have shown that polyhedrosis morbidity in the western Siberian population of the insect is relatively low, compared to that reported for North American and European populations. A possible cause of this situation is found in the high migration activity of moths in the Asian L. dispar populations, which allows the virus load on the biotope to remain relatively stable and insufficient for the initiation of mass viral diseases during population outbreaks.__________Translated from Ekologiya, No. 3, 2005, pp. 222–226.Original Russian Text Copyright © 2005 by Ilinykh.  相似文献   

8.
Using the long-tailed tit (Aegithalos c. caudatus) as an example of the so-called irruptive species, the ecophysiological characteristics (body mass, fat reserves) and migration speed during autumn period were analyzed. The mean body mass and the median fat score did not depend on the number of migrating individuals. There was no evidence of the so-called stress in birds, participating in migration: migrants had even higher fat reserves than residents, while no significant difference in the body mass was recorded. The increase in fat reserves in the long-tailed tit during migration period was similar to the seasonal changes in energy reserves known for typical migrants. This makes it possible for late-migrating individuals to maintain higher total speed of migration compared to early-migrating ones. Basing on the obtained data, we conclude that the ecophysiological characteristics of the long-tailed tits migrating in autumn are similar to those of regular migrants.  相似文献   

9.
The results of censuses taken in 1995 to 2011 along two key routes in the areas of the Sulakskaya and Turalinskaya Lagoons, Dagestan (the western coast of the Middle Caspian Sea), are summarized. The state of the populations of regularly migrating birds and causes of long-term fluctuations in their abundance have been assessed by the method of long-term series of observations on trajectories of active migration along stationary routes. The results show that the abundance of 46 out of the 116 background taxa has decreased, while that of 70 taxa has increased or remained unchanged. The key regulatory factors include hydroclimatic conditions, anthropogenic impact, food supply, synurbanization, and weather. The results provide a basis for developing a unified strategy for the conservation of the birds of Eurasia.  相似文献   

10.
The paper is devoted to the ecology of the Pied Flycatcher in Southern Karelia, where climate warming has had almost no effect on the weather in spring, the season especially important for birds. During the 30-year observation period, the local population has been characterized by variable breeding phenology, high fecundity, and relatively stable abundance. This appears to be related to the broad norm of reaction of this species to the action of external factors, which allows the birds to flexibly respond to changes in the unstable spring weather and adjust the timing and rates of their seasonal activities.  相似文献   

11.
12.
Molecular genetic methods (AFLP and ITS1–5.8S–ITS2 rDNA analysis) have been used to study the level and structure of genetic diversity in relict populations of the Ural endemic Gypsophila uralensis Less. in the northeast of European Russia. Intraspecific genetic differentiation is most clearly manifested between G. uralensis Less. subsp. pinegensis (Perf.) Kamelin locally endemic to the north of Europe (Arkhangelsk oblast, locus classicus) the population of G. uralensis Less. subsp. uralensis on limestone outcrops along the Shchugor River, the Subpolar Urals. The cluster of Timan populations (on limestone outcrops along the Svetlaya, Pizhma, and Myla rivers) is autonomous and genetically heterogeneous. Genetic distances between model G. uralensis s.l. populations are correlated with geographic distances. The size and abundance of relict populations show a descending gradient in the forest zone, and parameters of their genetic diversity [1] and unbiased expected heterozygosity have been found to decrease along this gradient.  相似文献   

13.
The distribution of nine chloroplast DNA haplotypes in four insular North-Atlantic and four European coastal Atlantic populations of Calluna vulgaris in the glacial zone of the range has been analyzed in comparison with that in six marginal southern populations in the nonglacial zone of the Atlantic and Mediterranean regions. As a result, two hypothetical Pleistocene refugia (HPRs) for this C. vulgaris population group have been revealed, one in the Cévennes mountain range and the other in the Southern Alps (Trento). Judging from the 1–FST value, it has been found that the group of populations in the glacial Atlantic zone and adjacent European coastal Atlantic region is genetically similar to the HPR in the Cévennes at a highly significant level (p ≥ 0.999) and less similar to the HPR in Trento; however, it differs significantly from other Mediterranean and Atlantic populations. It has been concluded that the most probable hypothetical Pleistocene refugium for the recent C. vulgaris populations of the northeastern Atlantic and European coastal Atlantic regions was in the west of the Mediterranean, in the Cévennes, while the additional refugium was in the Southern Alps. Possible directions of the postglacial dispersal and recolonization of habitats by C. vulgaris populations from the western Mediterranean to the northeast of the Atlantic and to Scandinavia have been revealed.  相似文献   

14.
The return of willow ptarmigans to the sites in which they nested the previous year has been studied using color banding. No factors influencing the return index have been revealed, except for its dependence in males on the time when spring begins in a given year. In northernYamal, in contrast to the temperate zone, some surviving birds fail to return to their former nesting sites. Polymorphism of individuals with respect to territorial behavioral strategy is proposed for L. lagopus populations at the northern boundary of the species range.__________Translated from Ekologiya, No. 3, 2005, pp. 215–221.Original Russian Text Copyright © 2005 by Tarasov.  相似文献   

15.
Based on analysis of the frequencies of nonmetric cranial characters, the ratio of interpopulation and interspecific differences has been studied in populations of two genetically identified cryptic species of wood mice, A. uralensis and A. ponticus, living under different ecological conditions in the Northern Caucasus. Hybridization between these species has not been reported previously, but interspecific phenetic distances indicate that differences between them do not exceed the level characteristic of subspecies, with morphological differentiation between A. uralensis populations of the Central and Western Caucasus being weakly expressed. It is hypothesized that the low level of intra- and interspecific differences is explained by the sympatric and symbiotopic origin of both species in the Western Caucasus. This may account for the retention of their similarity in ecological requirements for the environment and, consequently, only slight morphological disparity in similar biotopes.  相似文献   

16.
Comparative allozyme analysis of 26 marginal island populations of Pinus sylvestris L. and 20 populations from the center of the species range has confirmed, at the species level, the Wright-Dubinin “island model” of automatic genetic processes and Mayr’s hypothesis about homozygotization of small isolated populations at range boundaries. It has been shown that the polymorphism of isolated populations sharply decreases when their area is reduced below 15–20 km2 and increases to the level observed in the center of the range when the population area exceeds 50–100 km2. A chorogenetic classification of marginal P. sylvestris populations is proposed.  相似文献   

17.
Changes in the role of relict crustaceans in the zoobenthic communities of large subarctic Lake Imandra are analyzed over the long period of economic development in its drainage area. To date, Mysis relicta as a species highly sensitive to anthropogenic pollution has apparently disappeared from the lake fauna. The currently recorded maximum values of Pontoporeia affinis abundance and biomass are more than 20 times as great as those between 1968 and 1986. As in other lakes with mass development of P. affinis, the populations of this crustacean inhibit chironomid larvae in the communities of Lake Imandra.  相似文献   

18.
The distribution of Fe, Zn, Cu, Cd, Mn, Pb, and Ni in the organs and tissues (kidneys, liver, lungs, brain, heart, muscles, and feathers) of the European black vulture (Aegypius monachus) was studied. It was shown that heavy metals were not responsible for the mass mortality of these birds in southern Primorye in the winter of 2001–2002. The level of pollution with heavy metals of the range of European black vultures wintering in this region (northern China and western Mongolia) may be regarded as insignificant.  相似文献   

19.
In the HYENA study (HYpertension and Exposure to Noise near Airports) noise annoyances due to aircraft and road traffic noise were assessed in subjects that lived in the vicinity of 6 major European airports using the 11-point ICBEN scale (International Commission on Biological Effects of Noise). A distinction was made between the annoyance during the day and during the night. Lden and Lnight were considered as indicators of noise exposure. Pooled data analyses showed clear exposure–response relationships between the noise level and the noise annoyance for both exposures. The exposure–response curves for road noise were congruent with the EU standard curves used for predicting the number of highly noise annoyed subjects in European communities. Annoyance ratings due to aircraft noise, however, were higher than predicted by the EU standard curves. The data supports other findings suggesting that the people's attitude towards aircraft noise has changed over the years, and that the EU standard curve for aircraft noise should be modified.  相似文献   

20.
Gradients of Nei's genetic distances between 15 samples of Pinus sylvestris L. trees were analyzed along three submeridional transects, from Scandinavia to the Mediterranean and Transcaucasia. As a result, distinct chorogenetic differentiation was revealed between the populations of this species growing in climatically specific regions of northern and southern Europe. Considerable Nei's distances (DN = 0.045–0.056) and their gradients, combined with differences in stable phenotypic characters (the composition of monoterpenes and morphological parameters of cones) determined at the Pyrenean and Caucasian mountain borders, suggest that the P. sylvestris species structure includes two South Eurasian subspecies, the Pyrenean P. sylvestris L., ssp. iberica Svoboda and the Transcaucasian P. sylvestris L., ssp. hamata (Stev.) Fomin.  相似文献   

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