Habituation in mosquito larvae Aedes aegypti is context-specific

Mosquito larvae live in water and perform a stereotyped escape response when a moving object projects its shadow on the surface, indicating potential risk of predation. Repeated presentations of the shadow induce a decrease in the response due to habituation, a form of non-associative learning defined as the progressive and reversible decrease in response to a specific reiterative innocuous stimulus. Nevertheless, habituation can be context-specific, which indicates an association between the context and the stimulus. The aim of this work was to study context-specificity in habituation in mosquito larvae Aedes aegypti. Larvae were individually placed in Petri dishes. Underneath, black, white or black-white striped cardboards were placed as backgrounds (visual context). Larvae were presented with a shadow produced by a cardboard square (training) over the course of 15 trials. After the fifteenth trial, the background was shifted and the stimulus was presented once again (test). To analyse habituation in different contexts, we developed a series of learning curve models. We performed a Bayesian model selection procedure using those models and the data from the experiments to find which model best described the results. The selected model was a Power-Law learning curve with six parameters (habituation rate, context-specific asymptotic habituation response -with one parameter per context, i.e. 3 parameters-, response-increase, and autocorrelation) describing the whole experimental setup with a generalised r2 of 0.96. According to the model, a single habituation rate would indicate that habituation was independent of the context, whilst asymptotic habituation would be context-specific. If the background was shifted after training, there was an increase in the response in the test, evincing context specificity in habituation.

Tachykinin signaling inhibits task-specific behavioral responsiveness in honeybee workers

Behavioral specialization is key to the success of social insects and leads to division of labor among colony members. Response thresholds to task-specific stimuli are thought to proximally regulate behavioral specialization but their neurobiological regulation is complex and not well-understood. Here, we show that response thresholds to task-relevant stimuli correspond to the specialization of three behavioral phenotypes of honeybee workers in the well-studied and important Apis mellifera and Apis cerana. Quantitative neuropeptidome comparisons suggest two tachykinin-related peptides (TRP2 and TRP3) as candidates for the modification of these response thresholds. Based on our characterization of their receptor binding and downstream signaling, we confirm a functional role of tachykinin signaling in regulating specific responsiveness of honeybee workers: TRP2 injection and RNAi-mediated downregulation cause consistent, opposite effects on responsiveness to task-specific stimuli of each behaviorally specialized phenotype but not to stimuli that are unrelated to their tasks. Thus, our study demonstrates that TRP-signaling regulates the degree of task-specific responsiveness of specialized honeybee workers and may control the context-specificity of behavior in animals more generally.

Context-specificity of violence: Physical, psychological, and social dimensions of harm during the Taliban’s insurgency (2007–2009) in Pakistan

This article explores the Taliban’s insurgency (2007–2009) in Swat Valley (northern Pakistan) and the multiple meanings of violence in this context. A thematic analysis of data collected through qualitative fieldwork finds that the violence experienced by the victims was understood in three ways: physically as bodily harm, psychologically as terror and fear, and socially in the form of humiliation and dishonor. By delving into the experiences of civilians, the article offers a victim-centered approach and argues that instances of violence were characterized by harm as a “core referent.” It further argues for a context-specific understanding of harm and explicates that this notion is also determined by the local culture of Swat Valley, Pashtunwali.

Valuing the Invaluable(?)—A Framework to Facilitate Stakeholder Engagement in the Planning of Nature-Based Solutions

Nature-based solutions (NBS) have emerged as an important concept to build climate resilience in cities whilst providing a wide range of ecological, economic, and social co-benefits. With the ambition of increasing NBS uptake, diverse actors have been developing means to demonstrate and prove these benefits. However, the multifunctionality, the different types of benefits provided, and the context-specificity make it difficult to capture and communicate their overall value. In this paper, a value-based framework is presented that allows for structured navigation through these issues with the goal of identifying key values and engaging beneficiaries from the public, private, and civil society sector in the development of NBS. Applied methods such as focus groups, interviews, and surveys were used to assess different framework components and their interlinkages, as well as to test its applicability in urban planning. Results suggest that more specialized “hard facts” might be needed to actually attract larger investments of specific actors. However, the softer and more holistic approach could inspire and support the forming of alliances amongst a wider range of urban stakeholders and the prioritization of specific benefits for further assessment. Consequently, it is argued that both hard and soft approaches to nature valuation will be necessary to further promote and drive the uptake of NBS in cities.

Female putty-nosed monkeys ( Cercopithecus nictitans ) vocally recruit males for predator defence

Alarm calls can trigger very different behavioural changes in receivers and signallers might apply different alarm call strategies based on their individual cost-benefit ratio. These cost-benefit ratios can also vary as a function of sex. For instance, male but not female forest guenons possess loud alarms that serve warning and predator deterrence functions, but also intergroup spacing and male–male competition. In some forest guenons, the context specificity and alarm call repertoire size additionally differs between females and males but it remains unclear if this corresponds to similar sexual dimorphisms in alarm calling strategies. We here experimentally investigated whether general female and more context-specific male alarm calls in putty-nosed monkeys ( Cercopithecus nictitans ) had different effects on the opposite sex's behaviour and whether they might serve different female and male alarm calling strategies. We presented a leopard model separately to the females or to the male of several groups while ensuring that the opposite sex only heard alarm calls of target individuals. While female alarms led to the recruitment of males in the majority of cases, male alarms did not have a similar effect on female behaviour. Males further seem to vocally advertise their engagement in group defence with more unspecific alarms while approaching their group. Males switched alarm call types once they spotted the leopard model and started mobbing behaviour. Females only ceased to alarm call when males produced calls typically associated with anti-predator defence, but not when males produced unspecific alarm calls. Our results suggest that sexual dimorphisms in the context specificity of alarms most likely correspond to different alarm calling strategies in female and male putty-nosed monkeys.

High-order interactions maintain or enhance structural robustness of a coffee agroecosystem network

The capacity of highly diverse systems to prevail has proven difficult to explain. In addition to methodological issues, the inherent complexity of ecosystems and issues like multicausality, non-linearity and context-specificity make it hard to establish general and unidirectional explanations. Nevertheless, in recent years, high order interactions have been increasingly discussed as a mechanism that benefits the functioning of highly diverse ecosystems and may add to the mechanisms that explain their persistence. Until now, this idea has been explored by means of hypothetical simulated networks. Here, we test this idea using an updated and empirically documented network for a coffee agroecosystem. We identify potentially key nodes and measure network robustness in the face of node removal with and without incorporation of high order interactions. We find that the system’s robustness is either increased or unaffected by the addition of high order interactions, in contrast with randomized counterparts with similar structural characteristics. We also propose a method for representing networks with high order interactions as ordinary graphs and a method for measuring their robustness.HighlightsThe robustness of a coffee-associated ecological network is either increased or unaffected by the incorporation of high order interactions.A method is proposed for representing high order interactions in ordinary networks.A method is proposed to measure the robustness of networks with high order interactions.High order interactions may promote the persistence of diverse ecosystems.

Neuromodulation of Behavioral Specialization: Tachykinin Signaling Inhibits Task-specific Behavioral Responsiveness in Honeybee Workers

Behavioral specialization is key to the success of social insects and often compartmentalized among colony members leading to division of labor. Response thresholds to task-specific stimuli proximally regulate behavioral specialization but their neurobiological regulation is not understood. Here, we show that response thresholds to task-relevant stimuli correspond to the specialization of three behavioral phenotypes of honeybee workers. Quantitative neuropeptidome comparisons suggest two tachykinin-related peptides (TRP2 and TRP3) as candidates for the modification of these response thresholds. Based on our characterization of their receptor binding and downstream signaling, we then confirm the functional role of tachykinins: TRP2 injection and RNAi cause consistent, opposite effects on responsiveness to task-specific stimuli of each behaviorally specialized phenotype but not to stimuli that are unrelated to their tasks. Thus, our study demonstrates that TRP-signaling regulates the degree of task-specific responsiveness of specialized honeybee workers and may control the context-specificity of behavior in animals more generally.