An Evolutionary Interpretation of Gift-Giving Behavior in Modern Norwegian Society

We have studied gift giving at Christmas among 50 graduate students in Norway. The students invested more the closer the coefficient of relatedness. However, partners ranked highest, which is natural for people at the start of their reproductive career. All students gave to their parents, siblings, and children, most gave to their grandparents, and only a third gave to some, but not all, of their genetic aunts/uncles. Twenty percent gave to first cousins, and none to second or third cousins. Similar patterns for gifts received were found. There were also sex differences (e.g. women had larger exchange networks than men), and birth order effects. Firstborns spent more on relatives than laterborns. However, middleborns gave more to their male friends than both firstborns and lastborns. We conclude that the results are consistent with theories of kin selection, reciprocity, sex differences and birth order effects