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111.
112.
雄性根田鼠的同胞竞争及其对同性个体的气味识别   总被引:6,自引:2,他引:4  
采用两两互作实验并以尿标记来确定共居至成年的2雄性根田鼠同胞在行为竞争上的差异,之后在行为选择箱中分别观察它们对来自熟悉和陌生同性个体的新鲜尿气味的行为反应,以确定气味识别差异。结果表明:①雄性根田鼠两两互作时,尿标记的多少可以作为判断其社会等级的标准;②从属鼠对熟悉气味存在明显偏好,其对熟悉气味的访问时间、接近频次和自我修饰频次都显著高于陌生气味;③优势鼠则优先访问陌生气味,其对陌生气味的访问时间、嗅舔频次、嗅舔时间、自我修饰及反标记均显著高于熟悉气味;④对于陌生气味,优势鼠和从属鼠之间存在明显不同的行为反应模式。本实验结果提示,雄性根田鼠对同性尿气味识别的差异以及对陌生气味的行为反应,可能暗含着其领域防卫的信息。  相似文献   
113.
The concept of dominance poses several dilemmas. First, while entrenched in genetics education, the metaphor of dominance promotes several misconceptions and misleading cultural perspectives. Second, the metaphors of power, prevalence and competition extend into science, shaping assumptions and default concepts. Third, because genetic causality is complex, the simplified concepts of dominance found in practice are highly contingent or inconsistent. The conceptual problems are illustrated in the history of studies on the evolution of dominance. Conceptual clarity may be fostered, I claim, by viewing diploid organisms as diphenic and by framing genetic causality modestly through individual alleles and their corresponding haplophenotypes.  相似文献   
114.
Allofeeding is a common social display among adult Arabian babblers (Turdoides squamiceps). The sociology and rates of allofeeding were studied with a tame population of babblers at the Shezaf Nature Reserve in the Rift Valley, Israel. Allofeeding rate varies with the season and food availability. Experimental supplementation to the whole group or to certain individuals greatly increased the rate of allofeeding, but it did not change the social order of the interactions. The interactions were almost always unidirectional: the donor allofed an individual lower in rank. Most of the few exceptions were reciprocal allofeeding among pairs of low-ranking individuals, correlated with a change in dominance between a young male and a young female. Higher-ranking individuals sometimes interfered with allofeedings by lower-ranking ones, and receivers frequently refused to accept the food offered. Allofeeding may therefore be considered as a display of dominance. However, as dominance rank rarely changes, except in very young birds, we suggest that allofeeding interactions display the prestige of the donors, that is, the degree of dominance of one individual over the other.Electronic Supplementary Material Supplementary material is available for this article at .  相似文献   
115.
Chen  Xiongwen  Zhou  Guangsheng  Zhang  Xinshi 《Plant Ecology》2003,164(1):65-74
Spatial characteristics of sixteen tree species were analyzed by theinformation from 287 permanent plots in 1986 and 1994 on North East ChinaTransect (NECT). Some species expanded and some retracted theirdistribution extents. Betula costata andPhellodendron amurense spread most fast toward west andeast, respectively. All tolerant tree species extended their frontiers and allintolerant tree species retracted their frontiers except Betulaplatyphylla. The distribution area decreased for all species exceptBetula costata, Juglans mandshurica,Ulmus spp. and Fraxinusrhynchophylla.The patch sizes of Pinus koraiensis, Populusdavidiana, Phellodendron amurense,Juglans mandshurica, Fraxinusmandshurica, Betula dahurica,Picea spp., Abies nephrolepis andLarixolgensis decreased, however, the patch sizes of Quercusmongolica, Betula costata, Acermono, Tilia spp., Ulmusspp., Betula platyphylla and Fraxinusrhynchophylla increased. The frequency pattern of Populusdavidiana, Betula platyphylla,Fraxinus rhynchophylla and Betuladahurica changed significantly(p< 0.05). The dominance pattern ofPopulus davidiana, Tilia spp.,Juglans mandshurica, Betulaplatyphylla, Betula dahurica andAbiesnephrolepis changed significantly(p < 0.05). The spatial correlation betweenspecies changed, such as the spatial correlation between Larixolgensis and Betula platyphylla, Acermono and Ulmus spp. increased. The possiblecause of these changes might be climate change, disturbances and habitat loss.  相似文献   
116.
For the first time, the specific activities of chitinases, esterases, lipases and a serine protease (VCP1) produced by different isolates of the nematophagous fungus Pochonia chlamydosporia were quantified and compared. The isolates were grown for different time periods in a minimal liquid medium or media supplemented with 1 % chitin, 0.2 % gelatin or 2 % olive oil. Enzyme-specific activities were quantified in filtered culture supernatants using chromogenic p-nitrophenyl substrates (for chitinases, lipases and esterases) and a p-nitroanilide substrate (to measure the activity of the proteinase VCP1). Additionally, information on parasitic growth (nematode egg parasitism) and saprotrophic growth (plant rhizosphere colonisation) was collected. Results showed that the production of extracellular enzymes was influenced by the type of medium (p < 0.05) in which P. chlamydosporia was grown. Enzyme activity differed with time (p < 0.05), and significant differences were found between isolates (p < 0.001) and the amounts of enzymes produced (p < 0.001). However, no significant relationships were found between enzyme activities and parasitic or saprotrophic growth using Kendall's coefficient of concordance or Spearman rank correlation coefficient. The results provided new information about enzyme production in P. chlamydosporia and suggested that the mechanisms which regulate the trophic switch in this fungus are complex and dependent on several factors.  相似文献   
117.
We review winner-loser models, the currently popular explanation for the occurrence of linear dominance hierarchies, via a three-part approach. (1) We isolate the two most significant components of the mathematical formulation of three of the most widely-cited models and rigorously evaluate the components’ predictions against data collected on hierarchy formation in groups of hens. (2) We evaluate the experimental support in the literature for the basic assumptions contained in winner-loser models. (3) We apply new techniques to the hen data to uncover several behavioral dynamics of hierarchy formation not previously described. The mathematical formulations of these models do not show satisfactory agreement with the hen data, and key model assumptions have either little or no conclusive support from experimental findings in the literature. In agreement with the latest experimental results concerning social cognition, the new behavioral dynamics of hierarchy formation discovered in the hen data suggest that members of groups are intensely aware both of their own interactions as well as interactions occurring among other members of their group. We suggest that more adequate models of hierarchy formation should be based upon behavioral dynamics that reflect more sophisticated levels of social cognition.  相似文献   
118.
Ants may increase habitat heterogeneity by means of building ant-hills, thereby changing community species composition and ecosystem structure and functioning. We investigated plant height, coverage and abundance for each species and calculated species richness and diversity for ant-hills of Camponotus herculeanus differing in size (309.45cm2, 948.45cm2, 2124.90cm2 for the small, intermediate and large ant-hills, respectively). The dominant species was subsequently identified for the three size-classes of ant-hills and the mechanism underlying anthill community succession was derived. Our results showed that diurnal temperature fluctuation was greater in ant-hills than the surrounding flat soil, where the temperature of the ant-hills was higher in daytime but lower at night relative to the counterpart. The soil moisture was lower in center than in edge of ant-hills whose moisture was lower than the flat soil. Plant species diversity and richness were not significantly different among the three classes of ant-hills while the dominant species conspicuously changed. The importance value of the most dominant species, Kobresia uncinoides, increased significantly with increasing ant-hill size; the subdominant species was Galium aparine, Festuca ovina, Elymus nutans for the small, intermediate and large ant-hills, respectively. The dominance of grasses was significantly higher, but that of forbs was lower on ant-hills than in surrounding communities. The ant-hills were dominated by species from Cyperaceae and Gramineae while Compositae and Ranunculaceae dominated the surrounding communities. In addition, we discussed the possible mechanisms driving ant-hill community succession and the potential significance of ant-hills to the whole community composition and dynamics in the alpine meadow.  相似文献   
119.
2009年2月至2010年7月,在河南太行山猕猴国家级自然保护区济源管理局所辖的天坛山管护区,基于个体识别和野外跟踪,观察了一个野生太行山猕猴群(王屋1群, WW-1)的社会结构,采用随机取样法(Ad libitum sampling)记录了该群内成年个体之间、母系单元之间的竞争行为过程,进而依据"David得分法"构建了WW-1群内成年个体及母系单元间的优势等级, 并采用瞬时扫描取样法(Instantaneous andscan sampling)记录了成年个体到达投食区的移动顺序, 分析了平均移动序位与社会顺位的相关性。结果表明: 1)WW-1群体大小为41只个体, 由7个成年雄性和13个成年雌性以及21个未成年猕猴组成, 群内的成年雌性个体分别隶属于3个母系单元; 2)群中成年雄性、成年雌性、亚成年雄性、亚成年雌性、青少年雄性、青少年雌性、婴幼猴雄性、婴幼猴雌性的比例为1∶1.86∶0.29∶0.43∶0.86∶1.29∶0.14∶0, 且未成年个体占全群的51.2%; 3)WW-1群表现出严格的优势等级结构, 成年个体优势顺位由高到低依次是: 豁鼻>次红>白鼻>痞子>红脸>尖脸>小白脸>皱眉>光鼻>长毛>黑颊>小不点>斑点>斑眼>灰头, 母系单元间的优势顺位由高到低依次是红脸单元>长毛单元>斑点单元。研究结果提示, 太行山猕猴的社会结构为多雄多雌型; 成年雄性个体之间优势等级较成年雌性严格, 而成年雌性的社会顺位受所在母系单元社会顺位的影响; WW-1群的α位为成年雄性, 其在获取资源上具有优先性。  相似文献   
120.
非人灵长类雌性等级的研究方法   总被引:1,自引:0,他引:1  
在非人灵长类动物等级研究中, 有关判定与描述优势等级方法的选择至关重要。早期对旧大陆灵长类的等级研究主要关注雄性, 对雌性涉猎较少。目前主要应用攻击-屈服、取食、携婴、相互理毛等行为标准来研究灵长类的雌性等级, 也发现不同的物种往往有不同的雌性等级模式。依据社群结构的完整性将其分为线性等级与非线性等级, 并采用不同的方式进行描述。本文通过查阅文献资料, 对雌性等级的研究内容、判定标准以及描述方式进行论述, 以便抛砖引玉提高非人灵长类雌性等级的研究水平。  相似文献   
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