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The concept of contagion defines how attitudes, emotions, or behaviors spread within a specific group. Traditional models of social contagion account for network characteristics that define the spread of simple or complex ideas based on the degree of exposure of susceptible agents to their affected "contact neighborhood". However, these models understate two principal characteristics of real-world dynamics: (i) the competition among ideas of varying degrees of complexity (as observed in voting models) and (ii) the feedback-driven evolution of contagion complexity. Certain network features (e.g., network size, topology, neighborhood size) might favor the diffusion of competing simple or complex ideas, depending on their distinct characteristics. Furthermore, the dominant behavior disseminated may alter the agent's operational environment, thereby modifying the cost of influencing additional agents. For instance, in co-evolutionary games such as the tragedy of the commons, encouraging agents to collaborate in the context of abundant and untapped resources requires a costly and complex contagion; conversely, in situations of resource depletion, prompting agents to reduce excessive exploitation is less costly—in line with the pathway of simple contagion. In this report, we develop an agent-based model that incorporates all of these aspects. • We build a Socio-ecological model of pro-environmental behavior linked to resource use. • Varied social network configurations influence behavior spread in our analysis. • Social relationships crucial in coordinating collective action. • Results emphasize social ties' crucial role in coordinating collective efforts. [ABSTRACT FROM AUTHOR]

• We model how individuals in groups benefit from others' vigilance via visual cues. • When others flee from a predator, the cues can be received even without attention. • Our model shows a split lateral field receiving more cues than a same-sized frontal one. • A lateral visual field > 180° supports similar survival as a frontal one > 240°. • Longer chains of information transmission lead to the advantage of the lateral field. Group living is of benefit to foraging individuals by improving their survival, through passive risk dilution by sheer numbers and through increasingly more active processes, ranging from cue transmission to alarm calling. Cue transmission of information within a group cannot easily be tracked in the field, but can be studied by modelling. An unintentional visual cue can be given by a fleeing action, and when it occurs in the visual field of an individual, can by contagion incite it to flee as well, making such a cue functional in anti-predator warning. The visual field is limited not only by morphology, causing a blind angle at the back, but also by behaviour. For instance, foraging with the head down can cause an extra "blind" angle in front for cues from other individuals, changing an unobstructed frontal visual field to a split lateral shape. The questions of the present study are: how do visual fields, in terms of their size and blind angles, influence survival of individuals in a group through their effect on non-attentional reception of cues to danger among group members after attentional detection of a predator, and how can we quantify this? We use an agent-based spatially explicit model to investigate the effect of contagious fleeing after detection of predators on survival rate. This model is a bottom-up model of foraging agents in a simple environment, where only assumptions about basic competences are made. We vary the size and the shape of the visual field (lateral, with the additional frontal "blind" angle, versus a frontal continuous view), the group size, the movement probability, and the style of movement (regular movement or start-stop movement) in residential groups. We devise a measure for the transmission rate and we measure the length of the transmission chains. We find that, as expected, in a residential group, a larger visual field enhances survival rate. Moreover, a lateral field is more effective than a frontal field of the same total size because it increases the field of vision and therefore the non-attentional reception of visual cues about danger during, for instance, foraging, for all but the largest visual fields. This is demonstrated by the higher transmission rates and longer chains of transmission for lateral fields. Better transmission for lateral visual fields results in more synchronized fleeing behaviour. As long as the visual field is large enough, having a blind angle in front does not detract from sufficiently effective transmission. These findings should be taken into account in empirical studies of vigilance in groups of foraging animals. [ABSTRACT FROM AUTHOR]