Reciprocity is a widely observed phenomenon for which evolutionary foundations are posited.
We conduct a dictator game in which recipients in an initial game become dictators in a second game. The amount sent by those sending back to the person from whom they received some or no dollars is strongly correlated with the amount received by them, although the interaction is one time and zero sum in nature. No such correlation between amounts sent and received is exhibited when second round dictators are instead paired with new partners. Intelligence and personality test results, gender, and other characteristics also help to predict sending behavior.