北塔山地区褐斑鼠兔的生活习性

褐斑鼠兔(Ochotona pallasi)又称帕氏鼠兔,在我国分布于内蒙古和新疆。其有关生物学资料,国内尚无专门的报道。我们于1975年6月、1976年7—8月,在新疆北部北塔山地区,对褐斑鼠兔的生活习性进行了观察和了解,现整理如下。     

蒙古黄兔尾鼠的生态观察

蒙古黄兔尾鼠(Lagurus przewalskii Buechner)是内蒙古和青海等省(区)荒漠草原的代表鼠种,因破坏草原和传播某些动物流行病而被列为重要害鼠之一。迄今为止,国内有关该鼠的生态研究尚无报道,为此,我们在1978年9月至1980年5月于内蒙古四子王旗北部的荒漠草原进行了蒙古黄兔尾鼠的生态学调查。现就观察结果总结如下。     

两种兔尾鼠的化学信息及其在群体中的作用

黄兔尾鼠(Lagurus lutens)及草原兔尾鼠(Lagurus lagurus)是新疆某些地区主要害鼠之一,它们的繁殖能力很强,数量高峰时,对草场危害极大。此外,它们还能传染某些地方性流行病,所以对这两种害鼠的防治是十分必要的。 近年来,我们在研究动物化学通讯的过程中,了解到外激素(信息素)在动物间传递信     

科氏鼠兔在昆仑山重新发现

科氏鼠兔(Ochotona koslowi Buchner)又称突颅鼠兔,隶属于兔形目(Lagomorpha),鼠兔科(Ochotonidae)。它是我国特产而古老的物种,曾广泛分布于我国北部,在周口店的中更新世地层中发现过化石。     

灰仓鼠和小家鼠种群16年动态分析

灰仓鼠(Cricetulus migratorius Pallas)和小家鼠(Mus musculus Linnaeus)在新疆北部农区田野众害鼠中种群数量居第二和第一位(新疆鼠害研究组,1975a,b;李春秋,1981),其数量消长有何规律?特点如何?两者同栖于农田,相互关系如何?有否促进或制约作用?这对鼠害防治工作颇具理论及实践意义。     

鼠类对敌鼠钠盐的敏感性与耐性的初步研究及其应用

敌鼠钠盐在近几年来已逐步推广使用,并取得较好的效果。一些作者曾用敌鼠钠盐对长爪沙鼠(Meriones unguiculatus)、高原鼠兔(Ochotona curzoniae)及小白鼠等作过毒力测定和现场灭鼠(夏武平1976,何新桥等1973),但对于我国常见的广布鼠种对敌鼠钠盐的敏感性和耐性方面的研究报告,仍为少见。耐性指中毒未死,抗药性增强,是后天获得的。为了正确合理地使用这一毒鼠剂,以利灭鼠工作的顺利开展,我们于1975年夏初曾以我国各地较常见的黑线姬鼠（Apodemus agrarius）、黄胸鼠（Rattus flavipectus）和褐家鼠（Rattus norvegicus）为实验动物,对这方面问题进行初步探讨,现报告如下。     

木垒草原兔尾鼠数量下降期种群结构变化

2000年9月至2001年9月在新疆木垒县分4个时段采用样方法对草原兔尾鼠(Lagurus lagurus)进行野外调查,实验室采用数学生态学方法研究草原兔尾鼠的种群年龄结构和繁殖结构变化。结果表明,随着草原兔尾鼠数量的下降,种群的年龄结构和繁殖结构都发生了明显的变化。     

不同海拔高原鼠兔个性特征与SERT基因多态性关联

个性特征是指动物个体间稳定、可遗传的行为差异,与相关基因多态性有关,反映了动物对环境的适应模式,探究个性相关基因变异,将有助于更好地理解动物对环境的适应与进化机制。本文以高原鼠兔 (Ochotona curzoniae) 为对象,研究了5个不同海拔地区高原鼠兔的个性 (探究性、勇敢性和温顺性) 差异特征,并检测了个性相关基因5-羟色胺转运体 (SERT) 的单核苷酸多态性 (SNP) 和mRNA表达。结果发现,高海拔地区高原鼠兔的探究性和勇敢性显著高于低海拔地区,而高海拔地区高原鼠兔SERT基因mRNA表达量显著低于低海拔地区,提示不同海拔高原鼠兔个性特征差异可能与SERT基因mRNA表达有所关联。进一步检测不同海拔地区高原鼠兔SERT基因多态性及其分布差异情况,发现该基因存在6个SNP (其中5个位于外显子3,1个位于外显子5 );不同海拔地区鼠兔基因分布差异分析显示外显子5的c.A1063C 同义突变与海拔之间存在显著相关,高海拔地区该位点CC基因型分布频率显著高于低海拔地区;c.A1063C的基因型虽然与探究性、勇敢性无显著相关,但与温顺性显著相关。综上所述,随着海拔升高,高原鼠兔探究性和勇敢性增加,这有利于动物获取更多的食物资源,进而增加其生存机会。与此同时,SERT基因多态性显示与不同海拔地区的生存环境相适应的特征,且与温顺性有关,暗示不同海拔高原鼠兔个性差异可能与SERT基因SNP的差异有关。本研究从基因表达与突变的角度尝试阐述高原鼠兔适应不同海拔环境的行为差异,显示了不同海拔地区高原鼠兔行为生存策略潜在的分子机制。     

两种家鼠的热能调节与地理分布关系

动物的生存与地理分布格局是长期自然选择的结果,其中包括热能调节的生理功能与环境的和谐适应。 褐家鼠(Rattus norvegicus)属全球性分布的动物,黄胸鼠(Rattus flavipectus)则主要栖居在我国长江流域以南广大地区。此两种鼠也是上海市室内的主要害鼠。我们通过对这两种鼠的热能调节的研究,观察到动物的热能调节对策与其地理分布格局具有密切相关的生态学特点。     

浙江西天目山的啮齿动物

我们于1963年5-7月,在浙江省西天目山的4个地区,对啮齿动物分布进行调查,为今后研究该地鼠类群落演替作对照,兹将调查结果简报如下: 据1525个铗日统计,共得啮齿动物8种;长吻松鼠(Dremomys pernyi),大仓鼠(Cricetulustriton),黑腹绒鼠(Eothenomys melanogaster),黑线姬鼠(Apodemus agrarius)黄胸鼠(Ra-ttus flavipectus),社鼠(R.confucianus),青毛鼠(R.bowersi),小泡巨鼠(R.edwardsi)。见表1。     

Reproductive behaviour of female Siberian lemmings during the increase and peak phase of the lemming cycle

The reproduction of female Siberian lemmings in the increase and peak phases of the lemming cycle was investigated in connection with a ship-borne expedition along the Siberian arctic tundra. The cycle phase of each studied lemming population was determined using demographic analyses, i.e. current density indices (captured lemmings per 100 traps per 24 h), information on previous density (frequency of old lemming faeces and runways), and information from dendrochronological analyses revealing the most recent winters with a high intensity of willow-stem scarring caused by lemmings. The cycle phase determination was corroborated with data on the age profiles of the populations. The reproductive behaviour of female lemmings differed markedly in relation to cycle phase. In increase-phase populations, all captured females (including young and winter born) were reproducing (had embryos or were lactating), and females started to reproduce early in life, i.e. when <2 months old. By contrast, in peak-phase populations, only 6% of the young females and 63% of the winter-born ones were reproducing, and females did not start to reproduce until they were 5–6 months old. The average number of embryos per reproducing female was significantly higher in increase-phase populations than in peak-phase ones. It is concluded that the rapid population growth in lemmings during the increase phase can largely be explained by the early (young age) reproductive start and, consequently, the shorter generation time, the high proportion of females taking part in reproduction, and the large litters produced. Similarly, a delay in the start of reproduction, a lower proportion of reproducing females, and smaller litter sizes produced by peak-phase lemming populations can contribute substantially to the deceleration in the population increase and possibly lead to a decline. Received: 14 June 1999 / Accepted: 15 November 1999     

Post-eclosion sensitivity to social context inPolistes dominulus Christ females (Hymenoptera,Vespidae)

Summary Polistes dominulus females were subjected to the following changes of social environment as soon as they emerged: females which emerged in young colonies (presumably most workers) were transferred to more mature colonies, and conversely, females which emerged in mature colonies (presumably mostly gynes) were transferred to younger colonies. The behavioural and biological data obtained here show that when exposed to the new social environment, females from young colonies were able to lengthen their life span and become gynes. Only the very first females to emerge from colonies were less able to survive hibernation. Conversely, females from mature colonies were able to become workers and, as a result of their participation in social tasks, had a shorter life span. This great plasticity in the roles which young adult females can adopt constitutes an important characteristic of primitively eusocial species.     

The summer decline of the collared lemming, Dicrostonyx groenlandicus, in high arctic Greenland

I studied the population structure and dynamics of the collared lemming, Dicrostonyx groenlandicus Traill, on Traill Island (NE Greenland) in 1998 to 2000. This is the first comprehensive study of a Greenlandic collared lemming population. During this period, population density continuously declined (>100 fold-decrease) from more than 10 ind/ha (peak year 1998) to less than 0.1 ind/ha (low year 2000), with the exception of one period of increase in the winter 1998–99. Several population parameters were correlated with these changes in density. Average body mass was greater in the peak year than in the intermediate year (1999) and greater in August than in July in both years. Growth rates were only positive in 1998 and only for young lemmings. Females had unexpectedly larger home ranges than males and were more mobile than males during the decline phase (1999). Poor recruitment and high predation rates (up to 3.4% per day for females in 1998) were the proximate causes of the summer declines in the study area. A simple calculation shows that even with a maximal rate of increase, this lemming population would not have been able to compensate for the high predation rate, and hence it necessarily faced a predation-induced summer decline during the part of population oscillation studied.     

Intra-and intercolony patterns of nest dispersion in the ant Lasius neoniger: correlations with territoriality and foraging ecology

Colonies of the ant Lasius neoniger have multiple nest entrances that are distributed throughout a colony's foraging area. Associated with each nest entrance is a group of workers that show strong fidelity to that nest entrance. Territorial expansion, as indicated by increases in the number of nest entrances per colony, is correlated with foraging activity. Although there is variation between colonies in the seasonal pattern of territorial expansion, most nests become active in early summer, increase the size of the area foraged until midsummer, and then decrease the number of active nest entrances in late summer. Over the study plot as a whole, the dispersion pattern of nest entrances changed from clumped, or tending to be clumped, in early spring to random in mid-and late summer. Within colonies, nest entrances were significantly overdispersed. Intra-and interspecific competition negatively affected foraging, and workers from a given nest entrance were most successful at retrieving prey less than approximately 15–20 cm from the entrance. The average distance between nest entrances within a colony was 37.7±3.3 cm (mean±95% confidence interval, n=115), which is approximately twice the distance at which workers can retrieve prey. The polydomous nest structure of L. neoniger appears to partition territory within a colony by spatial subdivision of its foragers, and thus may reduce loss of prey to competitors.     

Efficacy of modified hive entrances and a bottom screen device for controlling Aethina tumida (Coleoptera: Nitidulidae) infestations in Apis mellifera (Hymenoptera: Apidae) colonies

This study was designed to test whether hive entrances reduced with polyvinyl chloride pipe reduce the ingress of Aethina tumida Murray into Apis mellifera L. colonies and whether screen-mesh bottom boards alleviate side effects associated with restricted entrances. Forty-eight colonies distributed equally between two locations each received one of six experimental treatments: 1) conventional solid bottom board and open entrance, 2) ventilated bottom board and open entrance, 3) conventional bottom and 1.9-cm-i.d. pipe entrance, 4) conventional bottom and 3.8-cm pipe entrance, 5) screen bottom and 1.9-cm pipe entrance, and 6) screen bottom and 3.8-cm pipe entrance. Results were inconsistent between apiaries. In apiary 1, colonies with 3.8-cm pipe entrances had fewer A. tuzmida than colonies with open entrances, but this benefit was not apparent in apiary 2. Pipe entrances tended to reduce colony and brood production in both apiaries, and these losses were only partly mitigated with the addition of screened bottom boards. Pipe entrances had no measurable liability concerning colony thermoregulation. There were significantly fewer frames of adult A. mellifera in colonies with 3.8- or 1.9-cm pipe entrances compared with open entrances but more in colonies with screens. There were more frames of pollen in colonies with open or 3.8-cm pipe entrances than 1.9-cm entrances. We conclude that the efficacy of reduced hive entrances in reducing ingress of A. tumida remains uncertain due to observed differences between apiaries. Furthermore, there were side effects associated with restricted entrances that could be only partly mitigated with screened bottom boards.     

Reproduction of the Arctic copepodCalanus hyperboreus in the Greenland Sea-field and laboratory observations

The seasonal vertical migration of adultCalanus hyperboreus Krøyer and their female reproductive biology have been studied in the central Greenland Sea, based on 7-month coverage during one annual cycle. Females dwelled in surface waters only between April and July. Gonad maturation began after the summer descent into deeper waters between September and October in the absence of food. Breeding was assessed from gonad development and egg production experiments. It started around the beginning of November and was mostly completed by March/April, before the spring ascent. The overwintering depth of females ranged from close to the surface to 3000 m, and mature females had a preference for shallower depths. Males were mostly found during the breeding period, where they inhabited the 500- to 1000-m layer. Female dry weight was highest in August and November and lowest in February. Field observations were supplemented by observations on gonad development and egg production of females, which were collected in June and August and kept in the laboratory for up to 6 months. Clutch size, spawning interval and fecundity were determined at 0°C. Females collected in June were mature earlier. Due to their low dry weight, they developed only small gonads and very few of them spawned. Females from August were much fatter and produced up to 1000 eggs in several clutches deposited at regular intervals.     

内蒙东部地区绵羊中华双腔吸虫生物学和流行病学的研究

中华双腔吸虫(Dicrocoelium chinensis Tang et Tang,1978)的生活史虽经研究,但本吸虫在第二中间宿主及终末宿主体内发育的情况尚未经阐明(唐崇惕等,1980).内蒙科右前旗附近数个旗县是本吸虫的流行区,1980—1981年我们在那里进行本项工作,从     

On the evolutionary stability of the female-biased sex ratio in the wood lemming (Myopus schisticolor): the effect of inbreeding.

The evolutionary stability of the female-biased sex ratio observed in the wood lemming (Myopus schisticolor) is discussed. The hypothesis analysed is that the skewed sex ratio is maintained as a result of partial and/or recurrent inbreeding. Fredga et al. (1976, 1977) have suggested that an X-linked mutant gene, X, affects the male-determining action of the Y chromosome, thus converting some XY individuals into females. By a mechanism of selective non-disjunction in the foetal ovary only X-carrying eggs are produced. In particular the stability of that genetic mechanism (or the X chromosome) is analysed by considering the introduction of a "suppressing" sex-linked mutant gene Y. Several deterministic simulation models assuming father-daughter and/or brother-sister matings have been developed and analysed. It is concluded that in the case of extremely strong inbreeding, the hypothesised genetic mechanism may, as a result, be evolutionarily stable. Interpreting field observations on microtine rodents in general it is concluded that only a few species are likely to experience such extreme cases of inbreeding. The wood lemming and the related collared lemming (Dicrostonyx troquatus), another case which seems to have XY-females, are likely to exhibit sufficiently strong inbreeding.     

Functional and numerical responses of four lemming predators in high arctic Greenland

The high‐arctic tundra ecosystem has the world's simplest vertebrate predator–prey community, with only four predators preying upon one rodent species, the collared lemming (Dicrostonyx groenlandicus). We document the functional and numerical responses of all the four predators in NE Greenland. Using these data, we assess the impact of predation on the dynamics of the collared lemming with a 4 yr cycle and >100‐fold difference between maximum and minimum densities. All predator species feed mostly (>90%) on lemmings when lemming density is >1 ha^?1, but the shapes of the predators’ responses vary greatly. The snowy owl (Nyctea scandiaca) is present and breeds only when lemming densities at snowmelt are >2 ha^?1, giving rise to a step‐like numerical response. The long‐tailed skua (Stercorarius longicaudus) has a type III functional response and shifts from alternate food (mainly berries and insects) to lemmings with increasing lemming density. The skua surpasses all the other predators in summer by its total response. The type III functional response of the Arctic fox (Alopex lagopus) starts to increase at much lower lemming densities than the responses of the avian predators, but it has only a weak numerical response. Finally, the stoat (Mustela erminea) is the most specialized predator and the only one with a clearly delayed numerical response. According to their specific functional and numerical responses, each predator plays a key role at some point of the lemming cycle, but only the stoat has the potential to drive the lemming cycle. Stoat predation is greatly reduced in the winter preceding the lemming peak, and it reaches a maximum in the winter preceding the lowest lemming summer density. Stoat predation appears to maintain low lemming densities for at least two successive years. Our study provides empirical support for the specialist predator hypothesis about small mammal population cycles.     

Vocal communication in two lemming species (Lagurus lagurus and Eolagurus luteus)

The vocal repertoire of steppe (Lagurus lagurus Pallas, 1773) and yellow steppe (Eolagurus luteus Eversmann, 1840) lemmings consists of only one type of signal, namely, a squeak. The signal does, however, have considerable variability. The DFA standard procedure shows the significant differences in the parameters of squeaks between species and significant differences in squeak parameters between the sexes in steppe lemming but not in the yellow steppe lemming. The fundamental frequency of the smaller steppe lemming’s squeak is higher than that of the larger yellow steppe lemming, although the peak frequencies have comparable values. In addition, the steppe lemming displays a pronounced sexual dimorphism in vocalization parameters; the frequency characteristics of the signals of the smaller females have lower values, which are contrary to scaling laws, stating that smaller individuals tend to have higher fundamental and peak frequencies. The age-related variability in the signals of yellow steppe lemmings was also described. The fundamental frequency of their squeaks is higher than that of the adults, but the peak frequency of signals in young and adults is not distinguished, and its value is higher than theoretically calculated. Such deviation in signal frequency parameters from the optimum may be result of directed selection, indicating the high value of such signals in the acoustic communication of lemmings.