Carmichael, H. Lorne, and W. Bentley MacLeod. “Gift Giving and the Evolution of Cooperation”. Boston College Working Papers in Economics 338, 1997.
Gift giving is a practice common to many societies. In an evolutionary model the social custom of giving gifts at the beginning of a relationship can lead to trust and cooperation. The evolutionary approach makes predictions about the character of the goods that can be used as gifts. For example, gift goods may have little use value even at low levels of consumption. Although the gifts themselves are useless, the institution is not.