Social Affiliation in Zebrafish: From Synthetic Images to Biological Mechanisms

Zebrafish are small freshwater fish that inhabit the tropical waters (small lakes, rivers and streams) of Southern and Eastern portions of Asia, e.g. India and Nepal. This species has been becoming increasingly popular among behavioural neuroscientists for many reasons (e.g. [4, 15]). First, due to the past four decades of extensive developmental biology research conducted with this species, powerful genetic tools have been developed for it that now may be utilized by several other disciplines of biology, including brain and behaviour research. Second, the zebrafish appears to strike an optimal compromise between system complexity (it is a typical vertebrate with basic neuroanatomy, neurophysiology, neurochemistry, and biochemistry similar to those of higher order vertebrates including mammals) and practical simplicity (it is small, easy and cheap to maintain in the laboratory, and it is highly prolific) [2]. Third, due to these above features and because numerous genes identified in zebrafish have been found to have nucleotide sequences highly homologous to mammalian counterparts, the zebrafish is believed to be an excellent translational tool, i.e. it may be utilized for modeling and analysing human diseases [5].