Extremes within a Bird Family - Page 1
In most cases, closely related species have similar mating systems. This is probably due to their similar habitat and feeding behaviors. Ornithologists now believe that the ecological setting of a species helps determine what mating systems it uses.
The Sandpiper family, however, stands out among North American birds for its diversity of mating systems. This family runs the gauntlet of approaches to mating, from highly monogamous Dunlins to promiscuous Pectoral and Buff-breasted Sandpipers. In winter, all members of the Sandpiper family are remarkably similar in their behavior; most move about in great flocks and migrate enormous distances. On the breeding ground, however, their societies are organized in different ways.