Abstract

• Learning behaviour in a population evolves when it improves fitness of the individual. Interactions within the members of population may require the cognitive abilities which gives advantages in their lifetime reproductive fitness. Individuals may gather information and use the experience later in their life. In this study the learning behaviour of Betta splendens and its advantages in the social environment was investigated. It was hypothetized that organism will take advantages by learning from others, especially from the conspecific, to promote their lifetime reproductive fitness, in changing environment. Aggressive behaviour of two males Betta splendens were observed by the learners from separate tank (experiment 1). The social interaction between the winner from the first experiment and the learners were also observed (experiment 2). The learners received information through visual learning took advantages from prior experience. When learners encounters with the winners, they rarely compete to fight with them. In contrast, when they met with the losers, they always try to compete with them. The non-experienced individuals usually try to compete with each other unless they were injured during combat between them. These results clearly show that learners took advantages from prior social experience by showing behavioural plasticity in the changing environment. It was concluded that learning behaviour was simply evolved during the individual lifetime since adoption of learning gives some benefits to their life time reproductive fitness.