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Certain forms of gift-giving are customary among all or nearly all peoples. Often, the patterns are elaborate and the items given have a ritual specification and implication. Gifts may be presented among individuals, or between social groups to initiate or maintain alliances and mutually beneficial relations. The exchange of gifts for sex (almost invariably from male to female) occurs in many species, including many bird and spider taxa. Food sharing occurs among some nonhuman primatesmay be a precursor to human gift-giving, though it typically occurs only between social partners within a single group.
The Gift: The form and reason for exchange in archaic societies, , London and New York , (1990)
Kula; the Circulating Exchange of Valuables in the Archipelagoes of Eastern New Guinea, , Man, Volume 20, p.97-105, (1920)