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1.
The Australian Sphenomorphus group is a morphologically and ecologically diverse clade of lygosomine scincids, collectively comprising more than one‐half of the Australian scincid fauna. A previous phylogenetic analysis of mitochondrial 12S and 16S rRNA, and ND4 and adjacent tRNA sequences for a series of Australian Sphenomorphus group scincids recovered several well‐supported, major clades, although these were generally separated by relatively short branches associated with low support values. Applying a recently described methodology for inferring lineage‐level polytomies, I employ ATP synthetase‐β subunit intron sequences and the existing mitochondrial (mt)DNA data set (with sequences for additional taxa) to assess the hypothesis that the poorly resolved basal relationships within the Australian Sphenomorphus group are a consequence of the major clades having originated essentially simultaneously. Phylogenetic analyses of the separate mtDNA and intron sequence data reveal a number of congruent clades, including Anomalopus, Calyptotis, Ctenotus, Lerista, the Eulamprus quoyii group, the Glaphyromorphus crassicaudis group (including Glaphyromorphus cracens, Glaphyromorphus darwiniensis, and Glaphyromorphus fuscicaudis), Glaphyromorphus gracilipes + Hemiergis, Coeranoscincus reticulatus + Ophioscincus truncatus + Saiphos, and Eulamprus amplus + Eulamprus tenuis + Gnypetoscincus + Nangura. The relationships among these clades indicated by the two data sets, however, are generally incongruent. Although this may be partially ascribed to error in estimating phylogenetic relationships due to insufficient data, some incongruence is evident when uncertainty in inferred relationships is allowed for. Moreover, the congruent clades are typically separated by very short branches, several having a length insignificantly different from zero. These results suggest that initial diversification of Australian Sphenomorphus group scincids was rapid relative to the substitution rates of the mtDNA and intron fragments considered, if not essentially simultaneous. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society, 2007, 92 , 347–366.  相似文献   
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The food habits of the Iriomote catFelis iriomotensis were studied by analyzing 177 feces collected monthly from 1987 to 1988. A total of 26 food items were identified. The frequency of lizards and frogs in the feces was higher than those of mammals and birds. The food habits changed greatly seasonally.Eumeces skinks were fed on most frequently, and found in the feces with a similar high frequency occurrence in March–April and July–September, while their proportion to the total number of food items was larger in March–April than in July–September. The cats fed on larg-sized skinks, adultEumeces kishinouyei, more in March–April than in other seasons. The number of skinks sighted in the course of a road census was greater from March to August, and large-sized skinks were sighted more in March–April than in July–August. The cats fed selectively on large-sized skinks in every season. Therefore, changes in the food habits depended on the food availability. Characteristics of food habits in the Iriomote cat are discussed in comparison with the food habits of other felids in temperate and tropical regions.  相似文献   
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摄食对印度蜓蜥代谢率的影响   总被引:3,自引:0,他引:3  
通过测定摄食后印度蜓蜥雌性成体的耗氧量变化 ,研究摄食特殊热动力作用 (SDA)。动物分为摄食黄粉虫幼虫实验组和禁食对照组 ,两组蜥蜴平均体重无显著差异。测定耗氧量前 ,将所有动物在 3 0℃恒温室内禁食 3d。用容积为 3 0 0ml的封闭式呼吸室测定两组蜥蜴在 3 0℃条件下连续 3d的耗氧量 ,测定间隔时间为 4~ 2 5h。禁食组动物实验期间的耗氧量无显著的时间变异 ,实验组动物耗氧量的时间变异显著 ,这些结果表明摄食影响印度蜓蜥的代谢率。实验组动物摄食 8h后耗氧量已显著大于禁食组 ,摄食 3 0h后两组动物的耗氧量无显著差异。印度蜓蜥达到SDA峰值的平均时间约为 1 2 7h ,SDA峰值耗氧量是禁食对照组动物耗氧量的 1 6倍。印度蜓蜥单次摄食实验中的SDA具有进食后耗氧量迅速增加 ,达到峰值后下降至摄食前水平的典型模式。  相似文献   
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Tetra and tri‐nucleotide microsatellite loci were isolated from a parthenogenetic form of the Australian lizard Menetia greyii, using an enrichment method with polymerase chain reaction (PCR)‐based colony screening. Primers for 23 loci were designed and 11 of these loci amplified well in a panel of 10 parthenogenetic individuals from a single population. Seven loci were further characterized and six successfully amplified and were polymorphic in all five sexual species of the Menetia greyii complex they were tested in. These loci will be used to investigate the parental ancestry and clonal diversity of various parthenogenetic forms within the Menetia greyii species complex.  相似文献   
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Conservation strategies for the critically endangered Bermuda skink will require knowledge of genetic variation and population structure. We describe the isolation of six polymorphic microsatellites for this species suitable for use in population genetics studies or for monitoring success of potential breeding programmes. Tissue sampling for DNA extraction involved no blood loss or tail autonomy. Three of these loci cross‐amplify and are polymorphic in a related North American skink (Eumeces fasciatus) and should also be informative for this species.  相似文献   
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The geographical range of the five‐lined skink is the most expansive of any eastern North American lizard, ranging from previously glaciated southern Canada southward to the Gulf of Mexico and from the Atlantic seaboard west to Texas and Minnesota. The most northerly populations occur in southern Ontario and are of conservation concern. We developed six polymorphic dinucleotide microsatellite loci to examine the genetic structure within and among Ontario's populations and to examine the intrapopulation levels of genetic diversity relative to more southern populations.  相似文献   
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Abstract Animals frequently compete for resources (food, shelter, etc.) against conspecifics as well as against individuals of other species; larger animals typically are dominant over smaller ones. Although body size thus correlates with social dominance in interspecific as well as intraspecific encounters, the causal connection remains unclear. That is, one species might dominate another not simply because of larger size, but some other species‐specific attribute. In such a case, we expect an animal of the subordinate taxon to be subservient to all members of the ‘dominant’ species, even those too small to pose a physical threat. This scenario can be tested by staging encounters over resource use in the laboratory. We conducted such trials using a guild of sympatric montane lizards (Reptilia: Scincidae), that compete for shelter sites (rock crevices), with larger species routinely displacing smaller taxa. Remarkably, neonates of larger species effectively deterred adults of smaller species from entering occupied retreat sites – even when the neonates were much smaller than the adults they displaced. Thus, the outcomes of interspecific interactions in this system depend upon the species of the participants, not their relative body sizes. Measurements of bite force confirm that the neonates of the most dominant species posed little physical threat to heterospecific adults, so that species‐specific variation in fighting ability cannot explain this puzzling result. However, juveniles often share shelter sites with conspecific adults, so that avoidance of neonates may reduce the risk of attack by an unseen adult resident.  相似文献   
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