A model of the species rank-abundance relation for a community in an open habitat

Summary A mathematical model is proposed to describe the relationship between the abundance and the rank of species in order from the most abundant to the least in a community in an open habitat. This model is derived as a corollary of a species-area equation (Kobayashi, 1975) which could be expected in the case where the individuals of each species are uniformly distributed over a habitat area. Numerical simulation reveals that a rank-abundance curve for a universe results in different species-area or species-individual curves according to the spatial distribution of individuals, and that the relative abundance of each species in a sample varies with sample size unless the spatial distribution of individuals is uniform. A species-individual curve obtained bySanders’s (1968) rarefaction method agrees with that observed actually only for the spatially uniform distribution. Change in the pattern of rank-abundance curve with species diversity and with sample size is discussed in relation to the present model.     

Renationalisation of space in everyday life in Singapore

As globalisation becomes more and more familiar in our everyday lives, one readily visible phenomenon is the increasing number of migrants from outside the borders of nation states. This influx of migrants inevitably makes societies more complicated racially and culturally, and a ‘multi-racial’ or ‘multi-cultural’ society is no longer the monopoly of migrant societies such as the United States or Australia. This spread of multi-racial and multi-cultural societies in the world, however, does not mean that we have achieved racial and cultural co-existence (among nationals, and needless to say between host society and migrants) without hierarchies. In the face of a constant flow of migrants, both the host states and host societies need to control migrants, to ensure that migrants will co-exist with the host society as the host society wishes. Hierarchy and difference need to be created and maintained by the host society to control the influx of migrants in their everyday life. This paper explores how Singapore society draws a border between itself and female migrant domestic workers. For this purpose, it examines both everyday discourses of Singaporean employers about female migrant domestic workers and the efforts of the Singapore Muslim Converts’ Association to teach such workers to become ‘good Muslims'.     

How to Get a Longer Job? Roles of Human and Social Capital in the Japanese Labor Market

This article investigates the roles of human and social capital played in the Japanese labor market. Our research question is whether they interact to accelerate or decelerate each other to provide first jobs of a long duration. Based on the literature, we focus on the bonding functions of friends and relatives. Using the 2005 Social Stratification and Social Mobility Survey Data, we measure human capital by educational attainment (college education) and social capital by job search methods (using friends or relatives). The dependent variable is the hazard rate of turnover from the first job. We find that social capital especially benefits those with low human capital (high school graduates). When friends or relatives introduce workers to jobs, high school graduates tended to stay longer in their first jobs and had a lower turnover than college graduates did. This means that social capital decelerated effects of human capital. Therefore, in the Japanese labor market, social capital plays a complementary role in mitigating educational disadvantage.     

The subjective dimension of social isolation: A qualitative investigation of older adults' experiences in small social support networks

In the aging literature, social isolation has been primarily defined in terms of reduced support network size and low frequency of social contacts. Having a small social support network is associated with social isolation and an increased risk of physical and emotional vulnerability. However, this conceptualization ignores the contributions of a host of other factors, including life experiences, family dynamics, and long-term patterns of socialization. This paper argues that alongside quantitative assessments of support systems, the application of a life course perspective is needed to understand small social networks as lived experience. We report on findings from 28 in-depth interviews with older adults identified as being at risk of social isolation on the basis of the self-reported size of their social networks. We discuss these participants' experiences in the context of significant life course transitions such as marriage and widowhood.     

Interspecific relations in forest floor coleopteron assemblages: Niche overlap and guild structure

Summary In six different environments of the Towada-Hachimantai National Park, the forest floor coleopterons were sampled by means of pitfall traps with five different baits. Their niche breadths and niche overlaps were assessed for the electivity of habitat, bait, and habitat × bait, and compared with those expected from neutral models constructed randomly. The niche breadths in the observed assemblages were smaller than those expected from the neutral model, while the niche overlaps were more widely distributed than those expected from the neutral model. Mean overlaps between species neighbors in niche space, cluster analyses, and ordinations of species revealed a guild for habitat, bait and habitat × bait. Lawlor’s (1979) gamma matrices concerning the habitat electivity show that the rates of mutualism resulted from indirect interspecific competitions are significantly smaller in the guild than in the whole assemblage. This suggests that the interspecific competition among the guild members is mitigated or even converted into mutualism by joining of the species which do not belong to the guild. The rates of mutualism were also significantly larger in the resource state of two dimensions (habitat × bait) than in that of either one. Therefore, if niche overlaps are measured on the basis of resource state of multi-dimensions, the rates of mutualism may increase further.     

《德意志意识形态》"费尔巴哈"章的文献问题

本文以日本学术界关于《德意志意识形态》“费尔巴哈”章的文献学考证的争论为背景,分别从草稿的状态、几个争论的热点问题为切入口,就马克思哲学思想史上的这个重要学术文本提出了自己的观点,旨在于推动国际学术界继续在这一学术问题上向前迈进。     

The Use of Pitch Accent in Word–Object Association by Monolingual Japanese Infants

This study investigated the lexical use of Japanese pitch accent in Japanese‐learning infants. A word–object association task revealed that 18‐month‐old infants succeeded in learning the associations between two nonsense objects paired with two nonsense words minimally distinguished by pitch pattern (Experiment 1). In contrast, 14‐month‐old infants failed (Experiment 2). Eighteen‐month‐old infants succeeded even for sounds that contained only the prosodic information (Experiment 3). However, a subsequent experiment revealed that 14‐month‐old infants succeeded in an easier single word–object task using pitch contrast (Experiment 4). These findings indicate that pitch pattern information is robustly available to 18‐month‐old Japanese monolingual infants in a minimal pair word‐learning situation, but only partially accessible in the same context for 14‐month‐old infants.     

Estimation of the individual number entering each development stage in an insect population

Summary A method for estimating the number entering each development stage from data obtained by regular sampling through one generation of an insect population was described. This method is consisted of the following two procedures: The provisional estimates are calculated on the assumption that each stage has a common mortality in a sampling interval. Then these estimates are corrected on another assumption that the mortality is different in each stage but constant during a stage. The result of testing its validity with two laboratory populations of the common cabbage butterfly,Pieris rapae crucivora, showed the availability of the present method.     

Dispersive behaviour of larvae of the common cabbage butterflyPieris rapae crucivora

Summary To investigate the aggregative nature of the larvae ofPieris rapae crucivora, each 50 individuals of the 4th and 5th instar larvae collected from cabbage farms and reared under crowded and solitary conditions were released on an experimental arena and their dispersive behaviour was observed with the lapse of time. Both the 4th and 5th instar larvae showed the trend to approach toward random distribution when they were released under clumped condition, and they maintained random distribution when they were released at random. Therefore, it may be concluded that the larvae have not any aggregative nature caused by the mutual attraction among individuals. However, as the larvae reared in crowds sometimes showed the slight aggregative behaviour, it seems that the larval dispersal is different between densely and sparsely populated plants in field.     

Can I Trust You? Laterality of Facial Trustworthiness in an Economic Game

People tend to turn their left or right cheek to express or conceal emotions, respectively. We examined the lateral posing bias for displaying trustworthiness during a trust game in which participants and their virtual partners cooperated or did not cooperate with their counterparts to earn a monetary reward. Right-handed participants (N = 81) were asked to pose for a photograph and then play the trust game. Participants showed an overall left posing bias (i.e., showing their left cheek to the camera). The left cheek bias was more stable for participants that cooperated very little in the trust game (non-cooperators) than for those that cooperated a lot (cooperators). In the rating experiment (N = 28 and 25), non-cooperators showing their left cheek were rated equally as trustworthy as cooperators. On the other hand, non-cooperators who showed their right cheek were rated as less trustworthy than cooperators. These results suggest that non-cooperators intuitively use the left hemiface to exploit others in social interactions.