鄂尔多斯高原库布齐沙地三趾跳鼠静止代谢率的季节变化

三趾跳鼠的代谢率存在季节性变化 ,春季的静止代谢率最低 (0 75mlO2 /h .g) ,仅为期望值的 6 4% ,热中性区最窄 (2 9～ 31℃ ) ;夏季的代谢率 (1 17mlO2 /h .g)与期望值一致 ,热中性区最宽 (2 8～ 37℃ ) ;秋季的代谢率 (1 31mlO2 /h .g)高于期望值 10 % ,热中性区向低温偏移 (2 6～ 30℃ )。三趾跳鼠各季节的体温从春季到秋季逐渐降低 ,并且在环境温度为 30℃以下时基本维持恒定 ,高温时动物以耐受一定程度的高体温和分泌唾液防止致死性过热。三趾跳鼠的能量代谢特征不仅与季节性食物和环境温度变化有关 ,而且与该鼠种的冬眠特性也有一定联系     

Phylogeny of Glaucosomatidae inferred from molecular evidence

Most species of glaucosomatids (Teleostei: Glaucosomatidae) are endemic to Australia, except Glaucosoma buergeri that is widely distributed from Australia to Japan. This study elucidated phylogenetic relationships among glaucosomatids based on the morphological characters of the saccular‐otolith sagitta, in addition to molecular evidence of mitochondrial 16S rDNA, cytochrome oxidase I (COI) and cytochrome b (cyt b) sequences, and nuclear rhodopsin sequences. The topologies of individuals' phylogenetic trees, based on 16S rDNA, COI and cyt b sequences, were statistically indistinguishable from one another, and were only slightly different from a tree based on rhodopsin sequences. These molecular tree topologies, however, differed from species relationships in morphology‐based phylogenetic hypothesis proposed in previous studies. Specimens of G. buergeri from Australia and Taiwan showed differences in the sagitta and molecular differentiation at the four genes, suggesting a possible speciation event. Both molecular and morphological evidences indicate that Glaucosoma magnificum is the plesiomorphic sister species of other glaucosomatid species. Glaucosoma hebraicum is the sister species of a clade composed of G. buergeri and Glaucosoma scapulare. Molecular and morphological evidences also support the species status of G. hebraicum.     

Otolith and somatic growth rates in Atlantic salmon parr, Salmo salar L: evidence against coupling

It is often assumed that otolith growth is in some way dependent on somatic growth (i.e. that the two processes are coupled). We examined the relationships between sagitta radius and fork length in 0+ Atlantic salmon parr that would subsequently smolt aged 1 + (UMG fish) or 2+ (LMG fish). Repeated measurements of fork lengths of individually marked parr, taken over a 211-day period from first feeding, were compared to sagitta radii on the same measuring dates (obtained by analysis of daily increments). The results showed that there was a linear relationship between fork length and otolith radius in UMG parr. However, this was not true for LMG parr. These fish enter a state of natural anorexia in their first autumn (despite excess food), but their otoliths continued to grow at the same rate despite the virtual cessation of somatic growth; they had therefore developed disproportionately large otoliths by the end of the study period. The relative growth rates of soma and otoliths first changed in LMG fish in late July/early August; this is the most precise estimate yet obtained of the timing of divergence in the developmental pathways of UMG and LMG parr. The rate of sagitta accretion was consistently lower in LMG parr, possibly indicating a lower metabolic rate in these fish. The results are discussed in relation to previous theories of the relationship between otolith and somatic growth.     

Habitat residency and movement patterns of Centropomus parallelus juveniles in a subtropical estuarine complex

Sixty Centropomus parallelus juveniles were collected in March 2013 in two locations (Tromomó and Guaraguaçu) inside the Paranaguá estuarine complex, southern Brazil. The habitat residency and movement patterns of the individuals were inferred from Sr:Ca ratios and age recorded in the otoliths. Data suggest that the species spawns preferentially in brackish areas mainly from October to January, and that growth rate during the early juvenile stage could be influenced by environmental salinity. Furthermore, the data also show that C. parallelus can occupy diverse salinity habitats and migrate among marine, brackish and freshwater areas within the Paranaguá estuarine complex, showing a high environmental plasticity and adaptation.     

箭叶橐吾挥发油化学成分的研究

运用气相色谱-质谱-计算机联用技术,结合标准谱库,对青海产箭叶橐吾的挥发油成分进行了研究,分离鉴定了39个化合物,主要成分为2-甲基丁烯酸(5．001％)、顺-β松油醇(2．082％)、反-β-松油醇(4．069％)、4-甲基-1-异丙基-R-3-环己烯-1-醇(15．467％)、十二烷(2．181％)、十四烷(2．276％)、Tau．-Muurolol(3．108％)、α-杜松醇(5．682％)、十六醛(2．266％)、6,10,14-三甲基-2-十五烷酮(3．421％)、三十烷(2．370％)、二十五烷(3．766％)等。     

青藏高原东缘同域分布的2种橐吾属杂草的合子前生殖隔离

生殖隔离是阻止种间杂交、保持物种完整性和独立性的关键,对生物多样性的产生和维持有重要意义.不同物种间的生殖隔离形成阶段、方式和强度不完全相同,因而对物种间隔离机制的研究有助于揭示物种形成和维持机制.对青藏高原东缘同域分布的2种橐吾属杂草黄帚橐吾和箭叶橐吾的花期物候观察、访花昆虫观察及花粉-柱头亲和性进行研究,分析了2种橐吾多种合子前生殖隔离机制的特点及其在生殖隔离中的作用.结果表明: 黄帚橐吾种群花期比箭叶橐吾早20 d左右,虽然盛花期存在差异,但是2种群花期存在10 d左右的重叠期,并且在重叠期内2种橐吾花粉和柱头均具有活性.2种橐吾共享传粉昆虫,为泛化传粉模式,并且传粉者对2种植物的访花行为相似,存在2种植物间交叉访问.尽管2种橐吾花期不存在完全的时间隔离,也不存在完全的传粉者隔离,但2种橐吾柱头对异源花粉的亲和性差,表现为柱头对异源花粉有明显的排斥反应,异源花粉管在柱头上的生长过程明显受阻.这种花粉-柱头排异形式很有可能是2种橐吾属植物重要的合子前隔离机制,从而避免了种间的自然杂交,更好地维持了自然种群的多样性和遗传结构的稳定性.     

The differentiation of Stegastes partitus populations using lapillar and sagittal otolith chemistry

The comparison of elemental concentrations of sagittal and lapillar otoliths from the same individuals of Stegastes partitus indicated significant differences for several elements. Sagittal otoliths were superior at differentiating individuals, yet the differentiation of individuals was further improved when the elemental concentrations of both otolith types were used in the same analysis.     

浑善达克沙地三趾跳鼠的食性与繁殖特征的初步分析

采用夹捕取样法对内蒙古浑善达克沙地三趾跳鼠(Dipus sagitta)种群进行逐月调查,根据捕获样本的繁殖器官特征及胃内容物组成分析三趾跳鼠的食性与繁殖的季节动态。结果表明,本地区三趾跳鼠主要取食植物茎叶,4、5、6、9、10月植物茎叶占其食物组成的95%以上,7～8月达60%～75%;三趾跳鼠还取食少量的植物种子;7～8月,嫩绿的植物种子占35%,但很少取食成熟种子。此外,也捕食少量昆虫。在浑善达克沙地,三趾跳鼠每年只繁殖1胎,繁殖期为5～7月,5月下旬至6月中旬为交配期,6下旬至7月中旬为幼鼠出生期。三趾跳鼠的胎仔数稳定,每胎产仔2～3只,平均胎仔数为2·8。6月份成体雌鼠的妊娠率为43%;7月份雌鼠的妊娠率为48%;其他月份妊娠率为0%。雄鼠睾丸下降时间为5～8月,6月雄性成体睾丸下降率达到最高峰,为100%。