Sekhar, M. A. | Search bioRxiv

bioRxiv2025

A saga of agonistic interactions in house crickets (Acheta domesticus): A direct and indirect effects perspective

Agonistic behaviours are widely observed across multiple taxa and are critical in shaping hierarchies, influencing resource acquisition, survival, and reproductive success. Individuals often alter their behaviour in response to the traits of others, referred to as indirect effects. Individuals also differ in their mean behavioural responses, referred to as direct effects. The combination of indirect and direct effects produce the observed social interactions. Importantly, these effects are typically measured on isolated parts of the full sequence of behaviors and traits expressed during social interactions. Here, we used house crickets, Acheta domesticus, to investigate how direct and indirect effects shape behaviors and traits across an agonistic interaction. We found that the probability of initiating aggression, but not contact, was influenced by both direct and indirect effects independent of mass. Amplitude, peak frequency, and pulse duration of stridulations occurring during agonistic interactions were influenced by direct effects but were not strongly influenced by indirect effects. These results demonstrate that the strength of indirect and direct effects vary over the course of an agonistic interaction and differentially affect the specific components of these interactions. Understanding when and how these effects are important is necessary for understanding agonistic behaviour and its evolution.

animal behavior and cognition↗

bioRxiv2025

Social buffering as an indirect effect: mixed-effects modeling approaches

O_LIThe potential for an individuals social partners to buffer--or otherwise modify-- how individuals respond to their environment has been demonstrated to be important in many contexts. This buffering has the potential to affect responses to human modifications of environments. Unfortunately, statistical tools for identifying buffering effects have not been well developed. C_LIO_LIHere, we demonstrate how social buffering fits into the context of a phenotypic equation conceptual approach and then connects to mixed-effects modeling for estimating buffering and other modifying effects of social behavior. C_LIO_LIWe explore the power and accuracy for buffering in response to known environments, providing a guide for empirical investigation. We found that increasing the sampling of social interactions decreases bias and increases precision and power to a greater extent than increasing sampling of focal individuals. C_LIO_LIWe also introduce how buffering in response to unknown environmental variation can be statistically modeled and tested. If environments are unknown, social buffering can be statistically tested for using double hierarchical generalized linear models by including social partner identity as a random effect that influences residual variation. C_LIO_LIFinally, we discuss how these approaches fit into the broader literature on indirect effects and indirect genetic effects. Placing social buffering in the context of indirect effects reveals that the evolution of social buffering is affected by both variation in an individuals behavior and variation in how individuals affect each other. This has important implications for social and evolutionary organismal responses to changing environments. C_LI

animal behavior and cognition↗