首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
孙悦华  毕中霖 《动物学报》2003,49(3):389-392
Based on two specimens collected from Sichuan Province, Yang et al. (1989) described a new subspecies of the spotted little owl (Athene brama), the belly-mottled little owl (Athene brama poikila). This subspecies has been acknowledged by Cheng (2000). However, Cheng (2000) also mentioned that further work should be done on this subspecies. In 2001, we checked the specimen of Athene brama poikila in Ya’an, Sichuan and comparing them with the spotted little owl and the boreal owl (Aegolius funereus). The boreal owl is identifiable from its rather square facial disc, however, this character was destroyed during the facture for these two specimens of Athene brama poikila. That is the reason Yang et al.(1989) missed them with the genus Athene. The genus Aegolius is also identifiable from the genus Athene from the character on the toes, as the toes of the boreal owl are covered with thick feathers, whereas the toes of the little owl are bristled. The toes of these two specimens of Athene brama poikila are thickly feathered, corresponding to the identification of the genus Aegolius. The morphological characters and measurements of the two specimens also correspond to the boreal owl. The habitat of the two specimens was reported as conifer deciduous forest around 2 200 m to 3 100 m, which fits the habitat of the boreal owl. The distribution of the endemic Gansu subspecies of the boreal owl (A. f. beickianus) was reported at Tiantangsi, Lianhuashan in Gansu, Guinan in Qinghai and Jiuzhaigou in Sichuan in China, it was also reported at Lahul in north India, Sun et al. (2001) suggested that it is probably the boreal owl is also distributed in the conifer forest of west Sichuan and east Tibet. The new distribution point in Baoxing and Yajiang in Sichuan corresponds to this conjecture. As a conclusion, we believe that these two specimens should belong to the A. f. beickianus of the boreal owl .  相似文献   

2.
Summary We examined the food provision rate of male Tengmalm's owls,Aegolius funereus, during one 3 year vole cycle consisting of consecutive low, increase and peake vole years. The data were collected in the midnestling period when males provisioned the whole family. In the low vole year, males with a low loading index (g/cm2) of flying area fed their offspring more often than did males with a high loading index, whereas in the peak vole year the opposite trend was evident. Similar relationships were found in the food mass provisioned to the nest. In the increase vole year, male body size had no effect on feeding efficiency. In the peak vole year, when large voles are abundant, heavy males preyed on larger voles than were generally available in their territories, indicating that largeness may increase strike power in hunting attempts. In the low vole year, when breeding is costly due to food scarcity and extensive hunting area, small males are more economical fliers and efficient hunters than large males. The contrasting trends in correlations between male size and feeding efficiency in years of vole abundance versus scarcity suggest that no fixed phenotype may most efficiently cope with variable food supply.  相似文献   

3.
ERKKI KORPIMÄKI 《Ibis》1989,131(1):41-50
The mating system and mate choice of Tengmalm's Owls were studied in relation to population fluctuations of the staple food (voles) for seven years in western Finland. Three age classes of owls were differentiated: first-year, second-year and older owls. Despite a surplus of males, 11 % of them showed simultaneous bigyny in peak vole years. The mean distance between primary and secondary nests was 1158 m, and usually there was a free nest-box between the two nests. Because primary nests produced more fledglings than secondary ones and secondary nests produced fewer fledglings than simultaneous or even eight-days-later monogamous nests, this bigyny could be best explained by the 'deception' hypothesis.
In successive biandry, females deserted their first brood when young were still in the nest, thereby transferring the burden of raising the young to their males. The tendency of assortative mating by age (more yearling x yearling and + 2-year-old ×+ 2-year-old pairs than expected by chance) showed that females chose older males when these were available.  相似文献   

4.
BIRGER HÖRNFELDT  ULF EKLUND 《Ibis》1990,132(3):395-406
The breeding of Tengmalm's Owl Aegolius funereus was studied at Umeå, Sweden, during the 1984–85. Mean clutch-size was one egg larger in 1984 than in 1985 despite the later laying in 1984. The difference in clutch-size was related to a better food supply in 1984. Daily weight increase of females during the prelaying period showed a high negative correlation with laying date in 1985, and a high positive correlation with clutch-size independently of laying date in 1984–85. This suggested that food eaten before and during laying had a great and direct influence on both laying date and clutch-size. Many females increased in weight during laying and most others decreased only moderately (relative to egg weight), suggesting that body reserves were not a main source for egg production.
Late breeding females were provided with extra food during the prelaying and laying periods in 1985. Fed females weighed more, bred eight days earlier and laid one more egg than controls. At the same laying dates in mid season, and after heavy snow-fall, clutch-size and female weight were larger in the fed birds than in controls, but this was not so near the end of the laying season. Although the earliest of the fed late breeders weighed more, and probably were less restricted by food availability just before or during laying, they did not lay more eggs than did early breeders. This result suggested some limitation on clutch-size that could not be overcome by the supplementary feeding. Weights of females during laying did not show any consistent relationship with clutch-size during successive laying date intervals, suggesting that clutch-size was not directly related to body condition.  相似文献   

5.
6.
ERKKI KORPIMÄKI 《Ibis》1987,129(1):58-68
Timing of breeding in Tengmalm's Owl was studied in western Finland for 13 years. During 1973-85, half of the females started laying before 4 April, near the seasonal low of main food abundance (voles), and earlier than in southern Finland or as early as in southeastern Norway. The reason for this latitudinal trend is the shallow snow cover of the study area. The annual variation in the median laying dates was one month and was negatively correlated with the spring abundance of Microtus voles. The mean clutch size was related to the start of laying with early clutches being larger than late ones. These findings accord with the 'food limitation hypothesis', which states that laying begins as soon as the female can accumulate enough energy stores for forming eggs. Early breeding is adaptive, since juveniles of early clutches probably survive better during their first winter. In adults, early nesting improves the chances of rearing two broods per year, allows them to moult after breeding and gives more time to accumulate fat reserves to survive the winter. Tengmalm's Owl is one of the earliest breeders among North European birds. This is possible because of its hole-nesting and resident habits, small body-size in relation to the main prey and the greatest sexual size dimorphism among European owls.  相似文献   

7.
Genetic similarity among cultivars of Phyllostachys pubescens   总被引:1,自引:0,他引:1  
Phyllostachys pubescens is the most important economic bamboo species in China, which grows widely in the South of China. There are more than ten cultivars in this species but their genetic relationship still remains unknown. We used both amplified fragment length polymorphism (AFLP) and inter-simple sequence repeat (ISSR) techniques to determine genetic similarity among ten cultivars of P. pubescens and two related species. Eight hundred and twenty seven bands, in which 495 are polymorphic, were detected using 15 pairs of AFLP primers whereas total 231 bands, in which 154 bands are polymorphic, were scored using 16 ISSR primers. Statistic analysis showed that the genetic similarity matrices obtained from these two sets of molecular markers had a significant correlation (R = 0.959, P = 0.013). The dendrogram generated with AFLP and ISSR markers could clearly genetically identify ten cultivars of P. pubescens that had high similarity with genetic distances ranging from 0.023 to 0.108, and could be divided into three groups based on their genetic variation and similarity. Our results suggest that these molecular markers are useful to genetically classify cultivars or varieties of a species, particularly a bamboo species.  相似文献   

8.
甘肃省莲花山鬼鸮繁殖巢址记述   总被引:1,自引:0,他引:1  
鬼鸮在世界上呈环北极分布,其甘肃亚种自1928年在甘肃西北部的天堂寺首次发现后,80多年来在甘肃一直未见报道,其它分布点亦非常零散。1999~2003年,作者在甘肃省莲花山区发现鬼分布,并记录鬼鸮繁殖巢址3个。鬼鸮营巢于针叶树的树洞中,雌雄共同育雏。  相似文献   

9.
鬼鸮甘肃亚种繁殖期叫声研究   总被引:2,自引:1,他引:2  
古远  方昀  孙悦华 《四川动物》2006,25(1):28-33
利用叫声回放和声谱分析对莲花山自然保护区鬼甘肃亚种(Aegolius funereus beickianus)繁殖期的叫声进行了研究。共记录了领域叫声、尖叫声等6种叫声,分析了各种叫声的特征及与行为的联系。发现不同地点录制的领域叫声存在差异,但同一个体的叫声也有变化。甘肃亚种的领域叫声和欧洲的指名亚种A.f.fu-nereus及北美的亚种A.f.richardsoni相比较,单音数量少,单音长度小,频率高,但差异不大。  相似文献   

10.
11.
The study deals with similarity among 25 species of the genus Trifolium represented by 134 accessions. Clustering of the species based on isozyme banding pattern of five enzymes revealed that T. repens was distinctly different from other species. T. repens and T. retusum formed independent clusters. The group of species comprising of T. pratense, T. cherleri, T. spumosum, T. subterraneum, T. resupinatum, T. alexandrinum, T. echinatum, T. constantinopolitanum and T. tembense exhibited considerable similarity to the second cluster. This group joined another group of five species, i.e. T. nigrescens, T. glomeratum, T. apertum, T. alpestre and T. hybridum with nearly 50% similarity. T. purpureum, T. hirtum, T. campestre, T. incarnatum, and T. argutum grouped separately. There was no marked difference for banding pattern among T. alexandrinum genotypes. T. alexandrinum showed close affinity with T. subterraneum and T. resupinatum. T. lappaceum, T. diffusum, T. campestre, T. incarnatum and T. argutum showed only 44.8% similarity with other Trifolium species. Grouping together of accessions belonging to individual species indicated that incompatibility among species under study had restricted interspecific hybridization. Species belonging to subgenus Lotoidea clustered with species of subgenus Trifolium. Chonosemium species T. campestre formed one cluster with two Trifolium species T. hirtum and T. incarnatum. T. nigrescens was placed quite apart from the T. repens.  相似文献   

12.
DNA polymorphisms among Arabidopsis thaliana ecotypes are widely used as genetic markers in map-based cloning strategies. New PCR-based molecular markers do not only facilitate molecular mapping, but can also be used to obtain reliable sequence information for cladistic analyses. We have used CAPS (cleaved amplified polymorphic sequences) markers and a direct sequencing strategy to estimate genetic similarity among eighteen Arabidopsis ecotypes. Sequences at four loci, two from the nuclear and two from a non-nuclaar genome, were analysed. For each ecotype more than 1000pb of sequence information was obtained, and genetic similarity was calculated from a total of 35 polymorphic sites using a character-based approach. Divergence ranged from zero up to 50 discordant characters among the 72 characters defined by the polymorphisms. Separate calculations based on the nuclear and the non-nuclear sequences were performed and revealed a number of common features, including the existence of small clusters of very closely related ecotypes separated from each other by extensive sequence divergence. Our results provide information useful especially to investigators setting up crosses for chromosome landing strategies.  相似文献   

13.
Fledgling behaviour and movement patterns throughout the post-fledging dependence period (PFDP), especially in relation to changing environmental conditions, have been rarely studied, despite the fact that this period is recognized as of crucial significance in terms of high mortality of juveniles. The PFDP can extend over quite a protracted period, particularly in birds of prey, and a knowledge of the movement patterns of individuals is fundamental for understanding mechanisms underlying survival, habitat use and dispersion. We radiotracked 39 fledglings of the Tengmalm’s owl (Aegolius funereus) in two years with different availability of prey: 2010 (n = 29) and 2011 (n = 10) and obtained 1455 daily locations. Fledglings reached independence on average in 45 days after fledging in 2010 (n = 22) and 57 days in 2011 (n = 6). Within years, the most important measures influencing the distance moved from the nest box were age of fledglings and number of surviving siblings present. Individual home range size and duration of PFDP in particular were dependent on maximal number of siblings seen outside the nest box. In the season with low prey availability fledglings were observed at greater distances from the nest box than in the year with higher prey availability (mean distance: 350 m in 2010 and 650 m in 2011) and occupied larger home ranges (mean: 30.3 ha in 2010 and 57.7 ha in 2011). The main factor causing these differences between years was probably the different availability of prey in these two years, affecting breeding success and post-fledging survivorship of the Tengmalm’s owls.  相似文献   

14.
15.
The subspecies of saddle-back tamarins (Saguinus fuscicollis) are known to be chromatically and morphologically diverse but little is known of the genetic basis for the observed morphological variation. The morphology of first generation subspecific hybrids can be compared to that of the parental subspecies to provide information on the extent and nature of genetic differences in morphology between subspecies. We compare two groups of saddle-back tamarin hybrids (S. f. illigeri × S. f. lagonotus and S. f. illigeri × S. f. leucogenys) to pure-bred members of their parental subspecies. These crosses were examined for heterosis, caused by allele frequency differences between the subspecies in combination with directional dominance. Thirty-nine craniofacial measurements were derived from three-dimensional coordinates of landmarks on 355 adult tamarin skulls. These measurements were corrected for sex differences and differences due to environment (wild-derived vs. laboratory-born) prior to analysis of hybridity. Sex differences were minimal for these traits. Environment had a more significant effect on craniofacial morphology. Laboratory environments produce larger faces but smaller orbits, anterior cranial vaults, and cranial bases. Significant heterosis was found for many individual traits and for the first principal component representing size and size-related shape measurements in the S. f. illigeri × S. f. lagonotus cross. The smaller samples involved in the S. f. illigeri× S. f. leucogenys cross led to a much lower number of statistically significant results, although most traits did display heterosis. Heterosis for craniofacial size was nearly statistically significant. These results suggest that there are large differences in allele frequencies among these subspecies of saddle-back tamarin for genes affecting craniofacial morphology. Based on these data we suggest that these subspecies are likely to be independent, largely isolated, evolutionary units. © 1993 Wiley-Liss, Inc.  相似文献   

16.
 The cowpea [Vigna unguiculata (L.) Walp.] is a morphologically and genetically variable species composed of wild perennial, wild annual, and cultivated forms that are mainly used for edible seeds and pods. In this study, genetic variation in 199 germplasm accessions of wild and cultivated cowpea was evaluated using an allozyme analysis. The results from this survey showed that wild cowpea exhibits genetic variation perfectly fitted with the existing morphological classification. The cowpea gene-pool is characterized by its unusually large size. It encompasses taxa (ranked as subspecies) that could be considered as different species considering the high genetic distances observed between accessions belonging to different taxa. These subspecies can be classified into three groups characterized by their breeding systems: perennial outcrossers, perennial out-inbreds, and inbred annuals. Allozyme data confirm this grouping. Perennial outcrossers look primitive and are more remote from each other and from perennial out-inbreds. Within this large gene-pool, mainly made of perennial taxa, cultivated cowpeas (ssp. unguiculata var. unguiculata) form a genetically coherent group and are closely related to annual cowpeas (ssp. unguiculata var. spontanea) which may include the most likely progenitor of cultivated cowpeas. Received: 15 June 1998 / Accepted: 29 September 1998  相似文献   

17.
18.
The distribution of identical and similar (phylogenetically related) types of hypervariable segment 1 (HVS1) of the mitochondrial DNA (mtDNA) was studied in human populations belonging to three Slavonic groups and nine ethnogeographic groups of Eurasia (total sample size 2772 people). The results testified to a common origin of West, South, and East Slavs and revealed a central place of West Slavs among all Slavonic ethnic groups. Mixing was shown to play a substantial role in the formation of specific features of all three Slavonic gene pools. The mitochondrial gene pools of the Slavonic ethnic groups proved to preserve features suggesting a common ancestor for these and South European populations (especially those of the Balkan Peninsula).  相似文献   

19.
Genetic-mathematical analyses have proved that some orthopaedic anomalies are interconnected, have genetic communion, one of its components being the general dysplasia of connective tissue.  相似文献   

20.
Although there is little doubt that the domestication of mammals was instrumental for the modernization of human societies, even basic features of the path towards domestication remain largely unresolved for many species. Reindeer are considered to be in the early phase of domestication with wild and domestic herds still coexisting widely across Eurasia. This provides a unique model system for understanding how the early domestication process may have taken place. We analysed mitochondrial sequences and nuclear microsatellites in domestic and wild herds throughout Eurasia to address the origin of reindeer herding and domestication history. Our data demonstrate independent origins of domestic reindeer in Russia and Fennoscandia. This implies that the Saami people of Fennoscandia domesticated their own reindeer independently of the indigenous cultures in western Russia. We also found that augmentation of local reindeer herds by crossing with wild animals has been common. However, some wild reindeer populations have not contributed to the domestic gene pool, suggesting variation in domestication potential among populations. These differences may explain why geographically isolated indigenous groups have been able to make the technological shift from mobile hunting to large-scale reindeer pastoralism independently.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号