查询词典 pikas

To detect potential influence from geographical isolation upon population differentiation in small mammals, the skulls of Tibetan pikas among three isolated populations in western Sichuan Province were systematically compared.

为探讨地理隔离对小型兽类种群分化的影响，本文系统比较了四川西部3个隔离藏鼠兔Ochotona thibetana种群在头骨形态上的异同。

No significant seasonal differences were observed in plateau pikas aggressive and affiliative behaviors from either low or high density populations. Additionally, no significant differences existed between populations with different densities.

在高原鼠兔的社会行为中，亲昵行为和攻击行为强度在不同种群密度间比较均无显著差异；在同一密度条件下，亲昵行为和攻击行为强度也没有表现出明显的季节性变化。

No significant seasonal variation was observed in moving distance and moving frequency of female plateau pikas in low density population, whereas moving distance and frequency varied significantly for males. Significant seasonal variations were shown in both females and males in high density populations.

低密度种群内，雄性高原鼠兔的地面移动距离和频次均呈显著的季节性差异，而雌性高原鼠兔的差异不显著；高密度种群内，雌、雄个体的地面移动距离和频次都具有显著的季节性差异。

The Tibetan brown bear, a close relative of the grizzly,tries to dig the pikas out of their burrows.Even hard-frozen soil presents little obstacle to a determined bear.

狐狸和熊。西藏的棕熊，一种灰熊的近亲，尝试着想把鼠兔从洞穴中挖出来，即使有坚硬的冻土阻隔。

There are also double climaxes in life expectancy curves of male: One is 7.413 months when the population is 7 months old, the other is 6.5 months when the population is 19 months old. Finally, the innate capacity of increase of plateau pikas is 0.4127, and there are two peaks in reproductive value curves: One is 2.0526 during the age group Mon.

本项研究结合Tanner(1978)提出的Jolly-Seber方法计算过程，用AutoCAD软件作出N-S流程图并用Turbo C语言开发出Jolly-Seber方法的应用程序；同时，也作出动态生命表和综合生命表的N-S流程图并在Turbo C环境下开发出应用程序。

The results show the following meanings. First of all, the population density of plateau pikas reaches maximum in September and decreases minimum in May at research site during the research period.

研究结果表明，研究期间高原鼠兔种群密度在每年9月达到最大值，每年5月种群密度最小。

The main results obtained are as follows:(1) Pineal melatonin content exhibited a circadian rhythm in pikas maintained in natural photoperiod conditions (P.001) both in Feburary and September.

在10月份的检测中，白天采样组鼠兔松果腺MLT含量的均值为：95.8±6.8微微克/松果腺（n=28），夜间组为316.1±30.1微微克/松果腺（n=32），二者的差异显著性水平为（P.001）。

Significant differences were shown in the observation times of females during the peak and the middle of the reproductive season at different densities. The observation time of the females was much longer in low density population than that in high density population. For males, there was no significant difference in observation time between or among population densities. At both low and high population densities significant seasonal variation was found in the duration and frequency of male plateau pikas observation behavior, nor was that of females.

结果表明：在繁殖盛期和繁殖中期，低密度种群内雌性高原鼠兔的观望时间均显著高于高密度种群内，而在其它两个时期内无明显不同；雄性高原鼠兔的观望时间在不同密度间比较均无显著差异；同一密度条件下，雄性高原鼠兔的观望行为持续时间和发生频次均表现显著的季节性变化，而雌性高原鼠兔无明显差异。

It is one of the most dominant small mammals and plays an important role in keeping the balance of the alpine meadow ecosystem.The aim of this paper was to investigate the level of genetic diversity and also to test the hypothesis of IBD for this old species.Samples of plateau pikas were collected from four natural populations（Haiyan,Xidatan E,Xidatan W and Kunlunshan populations）.

采用多态信息含量、期望杂合度、观测杂合度、基因流和基因分化系数对种群及物种的遗传多样性水平进行分析；计算各种群间的遗传距离、遗传相似度以及遗传距离与地理距离的相关系数，并进行UPGMA聚类分析。

The differentiation in skulls of Tibetan pikas in the three mountains was assumed to correlate with geographical barriers created by the uplift of the Qingzang Plateau.

本研究揭示了在进行藏鼠兔等小型兽类种及种下阶元划分时，除数理统计手段引入的必要外，尚应充分考虑不同地理区域种群可能已产生的局部分化。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。