Experimental Induction of Infanticide in Female Wattled Jacanas

Abstract

We induced infanticide experimentally in a free-living population of Wattled Jacanas (Jacana jacana). These tropical shorebirds have a polyandrous mating system and females compete among themselves for breeding opportunities with males. Severe fights occurred between females, leading to takeovers of male mates. Under these circumstances, infanticidal behavior (the killing of young of the previous female) by the replacement female would be adaptive if it led to more rapid reproduction with the usurped male. When opportunities for takeovers were created experimentally (by removal of resident females), replacement females killed or evicted three of four existing broods of chicks and sexually solicited four of five usurped males. These findings strengthen the hypothesis of sexually selected infanticide by extending its applicability to a species in which sex roles are reversed.