Tolerance of female co-breeders in joint-laying pukeko: the role of egg recognition and peace incentives

Joint laying, where multiple females contribute eggs to a single nest and provide parental care, is a rare breeding system in the avian world. Currently, little is understood about the fitness consequences that joint laying imposes on all members of a cooperatively breeding group, and this is necessary for understanding the evolution of this unusual breeding system. Here, we combine descriptive and experimental studies to understand the costs …