Emergence and development of the boldness personality trait in mangrove rivulus: a behavioral study of three life stages on Kryptolebias marmoratus (10, 60 and 110 days post-hatching)

Details

Supervisors

Silvestre Frédéric ; Justine Bélik

Faculty

Faculté des sciences

Degree label

Master [120] en biologie des organismes et écologie, à finalité approfondie

Abstract

enIt is well documented that animals, even within the same species, differ from one another in their behavior. These behavioral differences are known as personality. Behavioral personality or temperament refers to the variability of responses to the same stimulus among individuals, and it is consistent over time and across different contexts. In the animal kingdom, personality is generally divided into five main traits: aggressiveness, sociability, boldness, activity, and exploration. However, the emergence and development of these traits are not yet fully understood. Here, we focus on the trait of boldness and show when individualities appear and how they evolve with age in a model fish species, the mangrove rivulus which is kept under standardized environmental conditions in the laboratory. Using a behavioral test, the shelter test, that provides us with useful behavioral variables for assessing boldness in fish, we have discovered that individual differences are detectable from an early age in this species and that they evolve and persist as the fish age, especially for the behavioral variable of the total distance moved. Such persistent behavioral individualities have great chances to play a role in habitat utilization, the risk exposure or the reactions to environmental stressors. These individualities are likely to influence the ecological and evolutionary response in a whole population as the decision making of each individual is influenced by their personality. And because of our results on an isogenic fish kept in standardized conditions, further studies of non-genetic contributions should be considered.