Mowrer’s classical experiment on Social Behaviour in Rats is n excellent example of the generalizability of behaviouristic research (although Mowrer himself went on to work upon ideas from many different schools, later on), the 3 experiments below depict how social behaviour can be studied in a controlled setting: through rats.
They show and explain what could be the potential causes for issues such as displaced aggression, hoarding, dominance hierarchies, etc. as well as the development of cooperative or altruistic behaviours.
The following footage shows the patterns of various social behaviours in rats:
This footage shows how these patterns can be influenced and manipulated:
Lastly, this footage shows how competition occurs in rats, and leads to the establishment of hierarchies: