Search results for " social"
showing 10 items of 44717 documents
Cuticular hydrocarbon profiles differ between ant body parts: implications for communication and our understanding of CHC diffusion.
2020
Abstract Insect cuticular hydrocarbons (CHCs) serve as communication signals and protect against desiccation. They form complex blends of up to 150 different compounds. Due to differences in molecular packing, CHC classes differ in melting point. Communication is especially important in social insects like ants, which use CHCs to communicate within the colony and to recognize nestmates. Nestmate recognition models often assume a homogenous colony odor, where CHCs are collected, mixed, and redistributed in the postpharyngeal gland (PPG). Via diffusion, recognition cues should evenly spread over the body surface. Hence, CHC composition should be similar across body parts and in the PPG. To te…
Hierarchy is Detrimental for Human Cooperation
2015
Studies of animal behavior consistently demonstrate that the social environment impacts cooperation, yet the effect of social dynamics has been largely excluded from studies of human cooperation. Here, we introduce a novel approach inspired by nonhuman primate research to address how social hierarchies impact human cooperation. Participants competed to earn hierarchy positions and then could cooperate with another individual in the hierarchy by investing in a common effort. Cooperation was achieved if the combined investments exceeded a threshold, and the higher ranked individual distributed the spoils unless control was contested by the partner. Compared to a condition lacking hierarchy, c…
Sex-allocation conflict and sexual selection throughout the lifespan of eusocial colonies.
2018
AbstractModels of sex allocation conflict are central to evolutionary biology but have mostly assumed static decisions, where resource allocation strategies are constant over colony lifespan. Here, we develop a model to study how the evolution of dynamic resource allocation strategies is affected by the queen-worker conflict in annual eusocial insects. We demonstrate that the time of dispersal of sexuals affects the sex allocation ratio through sexual selection on males. Furthermore, our model provides three predictions that depart from established results of classic static allocation models. First, we find that the queen wins the sex allocation conflict, while the workers determine the max…
Eduardo Sojo: The architect of the satirical journalism in Spain and Argentina
2016
El artículo analiza la extensa obra de Eduardo Sojo a través de las publicaciones satíricas que fundó en España y en Argentina durante las últimas décadas siglo XIX. A partir de la indagación de algunas de sus caricaturas políticas se reconstruye su posicionamiento político en los diferentes contextos en los que desarrolló su obra y el impacto que suscitó en la opinión pública su discurso en favor de los valores republicanos y su reiterado repudio hacia el clero, en ambos países. This article analyzes Eduardo Sojós extensive work through the satirical publications, which he founded in Spain and Argentina during the last decades of 19 th century. By looking into some of his political cartoon…
Fitness costs of worker specialization for ant societies
2016
Division of labour is of fundamental importance for the success of societies, yet little is known about how individual specialization affects the fitness of the group as a whole. While specialized workers may be more efficient in the tasks they perform than generalists, they may also lack the flexibility to respond to rapid shifts in task needs. Such rigidity could impose fitness costs when societies face dynamic and unpredictable events, such as an attack by socially parasitic slavemakers. Here, we experimentally assess the colony-level fitness consequences of behavioural specialization in Temnothorax longispinosus ants that are attacked by the slavemaker ant T. americanus . We manipulate…
Assessment of genetically modified maize MON 87403 for food and feed uses, import and processing, under Regulation (EC) No 1829/2003 (application EFS…
2018
GMO; maize (Zea mays); MON 87403; ear biomass; Regulation (EC) No 1829/2003; International audience; aize MON 87403 was developed to increase ear biomass at early reproductive phase through the expression of a modified AtHB17 gene from Arabidopsis thaliana, encoding a plant transcription factor of the HD-Zip II family. The molecular characterisation data and bioinformatic analyses did not identify issues requiring assessment for food and feed safety. No statistically significant differences in the agronomic and phenotypic characteristics tested between maize MON 87403 and its conventional counterpart were identified. The compositional analysis of maize MON 87403 did not identify differences…
The current and future state of animal coloration research
2017
Animal colour patterns are a model system for understanding evolution because they are unusually accessible for study and experimental manipulation. This is possible because their functions are readily identifiable. In this final paper of the symposium we provide a diagram of the processes affecting colour patterns and use this to summarize their functions and put the other papers in a broad context. This allows us to identify significant ‘holes’ in the field that only become obvious when we see the processes affecting colour patterns, and their interactions, as a whole. We make suggestions about new directions of research that will enhance our understanding of both the evolution of colour …
The Unique Characteristics of the Horses for Humans Learning Purposes in Equine Assisted Learning Practice
2019
This article aims to encourage scientific discussion about one of the aspects of equine-assisted learning practice, the unique characteristics of the horse owing to how it is used in intervention programmes for human learning purposes. Equine-assisted learning is an innovative learning approach where human learning and development takes place through guided interactions between humans and horses. Although scientific interest towards human-horse interactions is becoming increasingly popular, evidence-based research has examined the relationship between humans and horses, and how such bonds may contribute to human learning and development is limited and lacks empirical support. This report pr…
Fight or flight trade-offs and the defensive behaviour of the mountain katydid, Acripeza reticulata
2020
The defensive repertoires of prey are shaped by diverse ecological and evolutionary demands. This can generate trade-offs between the components of defences, as in the classic ‘fight or flight’ dichotomy, or dedicated investment in a singular end, allowing individuals in better condition to mount a more effective defence all round. Further, sexual dimorphism may drive sex differences in such responses, although our understanding of the interaction between sexual selection and defensive behaviour is in its infancy. Deimatic, or ‘startle’, defences typically combine multiple protective strategies, such as camouflage and aposematism, with a rapid transition between them, and thus offer unique …
Anthropologie physiologique
2007
Les recherches de terrain en primatologie, particulièrement nombreuses et détaillées au cours des dernières décennies, nous ont montré de nombreux exemples d'adaptations physiologiques qui résultent de la co-évolution en fonction des caractéristiques des environnements propres à chaque espèce. Dans quelle mesure ces recherches en primatologie permettent-elles une meilleure compréhension des adaptations et des comportements de l'homme, en particulier de son comportement alimentaire ?