Kin recognition in zebrafish, Danio rerio, is based on imprinting on olfactory and visual stimuli

The evolution of cooperative behaviour requires mechanisms to avoid investing in conspecifics that are not increasing an individualʹs direct or indirect fitness. This suggests that selection should favour the capability of recognizing kin. One mechanism to discriminate between kin and nonkin is based on phenotype matching, when an individual learns a template of itself or of its kin and can later use this template to recognize even unfamiliar kin.