That’s not actually as easy to answer as you’d think. People study human social behaviour in lots of different fields. Although I got into it from studying biology, it is also studied by psychologists, social scientists, behavioural economists and anthropologists all with a slightly different angle.
I am interested in human social behaviour from a evolutionary point of view and like to compare human social behaviour with other social animals behaviour so I call myself a behavioural ecologist. Hope this helps.