Social buffering: we cope better in an unpleasant situation if we are not alone. Several animals also demonstrate this adaptation, such as zebrafish.
Faustino et al. (Scientific Reports, 2017) tracked freezing behavior and erratic movements of zebrafish in detail, and found that zebrafish handled an aversive stimulus better if they are not alone.
With the use of two cameras, fish were video monitored from the top and from a side view. EthoVision XT was used to track the animals and extract xyz coordinates. From these tracks detailed analysis of freezing behavior and erratic movements was performed to assess fear behavior in the zebrafish.