Melina Coelho da Silva, Adelino V. M. Canário, Peter C. Hubbard, Sara D. Cardoso, David Gonçalves
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引用次数: 0
Abstract
Understanding consistent inter-individual variability in animal behaviour, known as personality traits, is essential for exploring the mechanisms and evolutionary consequences of behavioural diversity. Aggressive behaviour influences survival, resource acquisition, and reproduction, so clarifying individual differences can enhance our understanding of ecological dynamics and improve experimental design accuracy in behavioural studies. In this study, ornamental male Betta splendens, a model organism for aggression research, were analysed for intra- and inter-individual variability in aggressive responses to their mirror image—a standard method for assessing aggression in fish—once per week, and their consistency was evaluated over three consecutive weeks There were significant differences in aggressive behaviour across individuals, with coefficients of variation ranging from 29 to 60%. While most fish exhibited the full suite of aggressive displays, some showed no aggressive behaviour, while others only displayed threat behaviours but did not advance to the attacks. The consistency of individual threat and attack behaviours varied, but repeatability was high overall (intra-class correlation coefficients ≥ 0.5), indicating that individual fish have different levels of aggression. There was habituation to the mirror assay, with aggression decreasing significantly by the second week, though the degree of habituation, a form of learning, varied among individuals in some behaviours. Air-breathing frequency correlated positively with aggression behaviours and can be considered an indicator to infer aggression level in this species. These results indicate that inter-individual variation in aggressive behaviour and habituation to repeated testing using the mirror assay should be considered in aggression studies using B. splendens and potentially in other species.
期刊介绍:
acta ethologica publishes empirical and theoretical research papers, short communications, commentaries, reviews and book reviews as well as methods papers in the field of ethology and related disciplines, with a strong concentration on the behavior biology of humans and other animals.
The journal places special emphasis on studies integrating proximate (mechanisms, development) and ultimate (function, evolution) levels in the analysis of behavior. Aspects of particular interest include: adaptive plasticity of behavior, inter-individual and geographic variations in behavior, mechanisms underlying behavior, evolutionary processes and functions of behavior, and many other topics.
acta ethologica is an official journal of ISPA, CRL and the Portuguese Ethological Society (SPE)