The effects of habitat density and the spatial distribution of food on the social behaviour of captive wintering American Tree Sparrows

1987 ◽  
Vol 65 (3) ◽  
pp. 522-526 ◽  
Author(s):  
David R. C. Prescott

Two artificial habitats containing 15% (low density) and 40% (high density) coniferous ground cover, and three feeding patterns representing different levels of spatial food distribution were used to investigate the effects of factors influencing individual spacing on the behaviour of captive, wintering American Tree Sparrows (Spizella arborea). Specifically, three aspects of social behaviour were examined: the frequency of agonistic encounters, the percentage of interactions initiated by dominants, and nearest-neighbour distances. Temperature effects were also considered. Interaction rates were lowest when food was most dispersed, and at higher temperatures. More interactions were recorded in the higher density habitat, as compared with the low density habitat, but the trend was reversed when food was highly dispersed. Nearest-neighbour distances decreased with increasing habitat density and food dispersion and were shortest in the high density habitat. Dominant birds initiated most encounters (70.7%), but less frequently when food was abundant or temperatures high, contradicting an assumption of previous models of optimal flock behaviour. It is suggested that these models, which rely on predicted changes in the allocation of available time by dominant birds to predict flock size, could be improved by considering the effects of habitat density and food dispersion, as well as differences in the social optimization strategies of different flocking species.

Author(s):  
L. Mulestagno ◽  
J.C. Holzer ◽  
P. Fraundorf

Due to the wealth of information, both analytical and structural that can be obtained from it TEM always has been a favorite tool for the analysis of process-induced defects in semiconductor wafers. The only major disadvantage has always been, that the volume under study in the TEM is relatively small, making it difficult to locate low density defects, and sample preparation is a somewhat lengthy procedure. This problem has been somewhat alleviated by the availability of efficient low angle milling.Using a PIPS® variable angle ion -mill, manufactured by Gatan, we have been consistently obtaining planar specimens with a high quality thin area in excess of 5 × 104 μm2 in about half an hour (milling time), which has made it possible to locate defects at lower densities, or, for defects of relatively high density, obtain information which is statistically more significant (table 1).


1975 ◽  
Vol 33 (02) ◽  
pp. 256-270
Author(s):  
R. M Howell ◽  
S. L. M Deacon

SummaryElectron microscopy and particle electrophoresis were found to be complementary techniques with which to complete the physical data from an earlier study on barium sulphates used to adsorb clotting factors from serum. The differences revealed by scanning electron microscopy (S. E. M.) in the physical shape of low and high density grades of barium sulphate particles appear to be of greater significance than charge as expressed by electrophoretic mobility, in determining whether or not precursor or preformed factor Xa is eluted.This conclusion was based on the finding that at pH values close to 7, where the adsorption from serum occurs, all samples with the exception of natural barytes were uncharged. However as the high-density, or soil-grade, was found by S. E. M. to consist of large solid crystals it was suggested that this shape might induce activation of factor X as a result of partial denaturation and consequent unfolding of the adsorbed protein. In contrast, uptake of protein into the centre of the porous aggregates revealed by S. E. M. pictures of low-density or X-ray grade barium sulphate may afford protection against denaturation and exposure of the enzyme site.The porous nature of particles of low-density barium sulphate compared with the solid crystalline forms of other grades accounts not only for its lower bulk density but also for its greater surface/gram ratio which is reflected by an ability to adsorb more protein from serum.Neither technique produced evidence from any of the samples to indicate the presence of stabilising agents sometimes used to coat particles in barium meals.


2016 ◽  
Vol 6 (2) ◽  
Author(s):  
Rosa Jaitin

This article covers several stages of the work of Pichon-Rivière. In the 1950s he introduced the hypothesis of "the link as a four way relationship" (of reciprocal love and hate) between the baby and the mother. Clinical work with psychosis and psychosomatic disorders prompted him to examine how mental illness arises; its areas of expression, the degree of symbolisation, and the different fields of clinical observation. From the 1960s onwards, his experience with groups and families led him to explore a second path leading to "the voices of the link"—the voice of the internal family sub-group, and the place of the social and cultural voice where the link develops. This brought him to the definition of the link as a "bi-corporal and tri-personal structure". The author brings together the different levels of the analysis of the link, using as a clinical example the process of a psychoanalytic couple therapy with second generation descendants of a genocide within the limits of the transferential and countertransferential field. Body language (the core of the transgenerational link) and the couple's absences and presence during sessions create a rhythm that gives rise to an illusion, ultimately transforming the intersubjective link between the partners in the couple and with the analyst.


Author(s):  
Gulbarshyn Chepurko ◽  
Valerii Pylypenko

The paper examines and compares how the major sociological theories treat axiological issues. Value-driven topics are analysed in view of their relevance to society in times of crisis, when both societal life and the very structure of society undergo dramatic change. Nowadays, social scientists around the world are also witnessing such a change due to the emergence of alternative schools of sociological thought (non-classical, interpretive, postmodern, etc.) and, subsequently, the necessity to revise the paradigms that have been existed in sociology so far. Since the above-mentioned approaches are often used to address value-related issues, building a solid theoretical framework for these studies takes on considerable significance. Furthermore, the paradigm revision has been prompted by technological advances changing all areas of people’s lives, especially social interactions. The global human community, integral in nature, is being formed, and production of human values now matters more than production of things; hence the “expansion” of value-focused perspectives in contemporary sociology. The authors give special attention to collectivities which are higher-order units of the social system. These units are described as well-organised action systems where each individual performs his/her specific role. Just as the role of an individual is distinct from that of the collectivity (because the individual and the collectivity are different as units), so too a distinction is drawn between the value and the norm — because they represent different levels of social relationships. Values are the main connecting element between the society’s cultural system and the social sphere while norms, for the most part, belong to the social system. Values serve primarily to maintain the pattern according to which the society is functioning at a given time; norms are essential to social integration. Apart from being the means of regulating social processes and relationships, norms embody the “principles” that can be applied beyond a particular social system. The authors underline that it is important for Ukrainian sociology to keep abreast of the latest developments in the field of axiology and make good use of those ideas because this is a prerequisite for its successful integration into the global sociological community.


Author(s):  
Jeffrey P. Copeland ◽  
Arild Landa ◽  
Kimberly Heinemeyer ◽  
Keith B. Aubry ◽  
Jiska van Dijk ◽  
...  

Social behaviour in solitary carnivores has long been an active area of investigation but for many species remains largely founded in conjecture compared to our understanding of sociality in group-living species. The social organization of the wolverine has, until now, received little attention beyond its portrayal as a typical mustelid social system. In this chapter the authors compile observations of social interactions from multiple wolverine field studies, which are integrated into an ecological framework. An ethological model for the wolverine is proposed that reveals an intricate social organization, which is driven by variable resource availability within extremely large territories and supports social behaviour that underpins offspring development.


Author(s):  
Samir Okasha

Inclusive fitness theory, originally due to W. D. Hamilton, is a popular approach to the study of social evolution, but shrouded in controversy. The theory contains two distinct aspects: Hamilton’s rule (rB > C); and the idea that individuals will behave as if trying to maximize their inclusive fitness in social encounters. These two aspects of the theory are logically separable but often run together. A generalized version of Hamilton’s rule can be formulated that is always true, though whether it is causally meaningful is debatable. However, the individual maximization claim only holds true if the payoffs from the social encounter are additive. The notion that inclusive fitness is the ‘goal’ of individuals’ social behaviour is less robust than some of its advocates acknowledge.


2021 ◽  
pp. 147821032110320
Author(s):  
Ann Christin Eklund Nilsen ◽  
Ove Skarpenes

Histories of statistics and quantification have demonstrated that systems of statistical knowledge participate in the construction of the objects that are measured. However, the pace, purpose, and scope of quantification in state bureaucracy have expanded greatly over the past decades, fuelled by (neoliberal) societal trends that have given the social phenomenon of quantification a central place in political discussions and in the public sphere. This is particularly the case in the field of education. In this article, we ask what is at stake in state bureaucracy, professional practice, and individual pupils as quantification increasingly permeates the education field. We call for a theoretical renewal in order to understand quantification as a social phenomenon in education. We propose a sociology-of-knowledge approach to the phenomenon, drawing on different theoretical traditions in the sociology of knowledge in France (Alain Desrosières and Laurent Thévenot), England (Barry Barnes and Donald MacKenzie), and Canada (Ian Hacking), and argue that the ongoing quantification practice at different levels of the education system can be understood as cultural processes of self-fulfilling prophecies.


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