Voelkl et al. 2015
Voelkl B, Portugal SJ, Unsöld M, Wilson AM & Fritz J 2015.
Matching times of leading and following suggest cooperation through direct reciprocity during V-formation flight in ibis.
Proceedings of the National Academy of Sciences 112/7: 2115–2120
One conspicuous feature of several larger bird species is their annual migration in V-shaped or echelon formation. When birds are flying in these formations, energy savings can be achieved by using the aerodynamic up-wash produced by the preceding bird. As the leading bird in a formation cannot profit from this up-wash, a social dilemma arises around the question of who is going to fly in front?
