Search results for "Social evolution"
showing 10 items of 54 documents
The reception of Marx's thought in the young Habermas
2018
RESUMEN Se analiza la influencia del pensamiento de Marx en la formulación temprana de la teoría habermasiana. Para ello, se parte de las críticas de Albrecht Wellmer y Jürgen Habermas a la autocomprensión marxiana del materialismo histórico. Luego se estudia la reconstrucción de algunos postulados del marxismo llevada a cabo por Habermas en términos de una renovada teoría de la evolución social. Con ello salen a la luz algunos supuestos básicos de la teoría de Marx que aparecen trasformados en la conceptualización de Habermas y que constituyen una base ineludible para comprender el posterior pensamiento de este autor. ABSTRACT The article analyzes the influence of Marx's thought on the for…
Gender role portrayals and sexism in Spanish magazines
2007
PurposeThe purpose of the paper is to analyse the male and female stereotypes in Spanish magazine advertising during the last three decades of the twentieth century in order to determine if they reflect or not the important cultural changes of Spanish society in these years.Design/methodology/approachContent analysis of 1,033 different advertisements randomly selected. To ensure reliability two independent codifiers of opposite gender worked together, one as an analyst and other as a judge. Three agreement indices were calculated.FindingsUse of male and female portrayals has undergone relevant changes in the last 30 years in accordance with the social evolution of Spain. For both men and wo…
Experimental increase of worker diversity benefits brood production in ants
2021
Background The reproductive division of labor of eusocial insects, whereby one or several queens monopolize reproduction, evolved in a context of high genetic relatedness. However, many extant eusocial species have developed strategies that decrease genetic relatedness in their colonies, suggesting some benefits of the increased diversity. Multiple studies support this hypothesis by showing positive correlations between genetic diversity and colony fitness, as well as finding effects of experimental manipulations of diversity on colony performance. However, alternative explanations could account for most of these reports, and the benefits of diversity on performance in eusocial insects stil…
Racism, Xenophobia and Intolerance
2015
Unlike what is usually assumed, racism is neither a phenomenon of the past nor exclusive to other latitudes. As Wieviorka points out (2009, p. 15), today there has been a surprising return of racism, even in societies that could be expected to be ridding themselves of it. Until the 1960s, the outlook clearly seemed optimistic, as the prevailing idea was that political and economic progress would end up burying phenomena of this type. This hypothesis, however, was soon revealed to be overly optimistic. Racism currently exists in European societies, and it is one of the great challenges of their present and future. Therefore, regardless of future social evolution, it is likely that European s…
Recent speciation and secondary contact in endemic ants
2014
Gene flow is the main force opposing divergent selection, and its effects are greater in populations in close proximity. Thus, complete reproductive isolation between parapatric populations is not expected, particularly in the absence of ecological adaptation and sharp environmental differences. Here, we explore the biogeographical patterns of an endemic ant species, Cataglyphis floricola, for which two colour morphs (black and bicolour) coexist in parapatry throughout continuous sandy habitat in southern Spain. Discriminant analyses of six biometric measurements of male genitalia and 27 cuticular hydrocarbons reveal high differentiation between morphs. Furthermore, the low number of shared…
Social Interactions Among Bacteriophages
2020
Although viruses lack many of the social adaptations shown by more complex organisms, different types of social interactions have been unraveled in viruses. Phage research has contributed significantly to the development of this field, called sociovirology, with the discovery of processes such as intracellular and extracellular public good production, prudent host exploitation, cheating, and inter-phage communication. We here review and discuss these processes from a social evolution approach. Similar to other organisms, the origin and maintenance of phage-phage interactions can be explained using kin selection, group selection and game theory approaches. Key determinants of phage social ev…
Comparative analyses of co-evolving host-parasite associations reveal unique gene expression patterns underlying slavemaker raiding and host defensiv…
2017
Abstract The transition to parasitism is a drastic shift in lifestyle, involving rapid changes in gene structure, function, and expression. After the establishment of antagonistic relationships, parasites and hosts co-evolve through reciprocal adaptations, often resulting in evolutionary arms-races. Repeated evolution of social parasitism and slavery among Temnothorax ants allows us to examine those gene expression patterns that characterize slavemaker raiding and reciprocal host defensive phenotypes. Previous behavioural studies have established that raiding strategies between Temnothorax slavemakers diverge, while host defense portfolios shift similarly under parasite pressure. We are the…
Survival after pathogen exposure in group-living insects: don't forget the stress of social isolation!
2016
A major cost of group-living is its inherent risk of pathogen infection. To limit this risk, many group-living animals have developed the capability to prophylactically boost their immune system in the presence of group members and/or to mount collective defences against pathogens. These two phenomena, called density-dependent prophylaxis and social immunity, respectively, are often used to explain why, in group-living species, individuals survive better in groups than in isolation. However, this survival difference may also reflect an alternative and often overlooked process: a cost of social isolation on individuals' capability to fight against infections. Here, we disentangled the effect…
Time-resolved classification of dog brain signals reveals early processing of faces, species and emotion
2020
Dogs process faces and emotional expressions much like humans, but the time windows important for face processing in dogs are largely unknown. By combining our non-invasive electroencephalography (EEG) protocol on dogs with machine-learning algorithms, we show category-specific dog brain responses to pictures of human and dog facial expressions, objects, and phase-scrambled faces. We trained a support vector machine classifier with spatiotemporal EEG data to discriminate between responses to pairs of images. The classification accuracy was highest for humans or dogs vs. scrambled images, with most informative time intervals of 100–140 ms and 240–280 ms. We also detected a response sensitive…
No synergy needed: ecological constraints favor the evolution of eusociality.
2015
In eusocial species, some individuals sacrifice their own reproduction for the benefit of others. It has been argued that the evolution of sterile helpers in eusocial insects requires synergistic efficiency gains through cooperation that are uncommon in cooperatively breeding vertebrates and that this precludes a universal ecological explanation of social systems with alloparental care. In contrast, using a model that incorporates realistic ecological mechanisms of population regulation, we show here that constraints on independent breeding (through nest-site limitation and dispersal mortality) eliminate any need for synergistic efficiency gains: sterile helpers may evolve even if they are …