Individual recognition, dominance hierarchies and winner and loser effects

• Published in: Proceedings of the Royal Society. B, Biological sciences Vol. 271; no. 1547; pp. 1537 - 1540
• Main Authors: Dugatkin, Lee Alan, Earley, Ryan L.
• Format: Journal Article
• Language: English
• Published: England The Royal Society 22.07.2004
• Subjects: Aggression - physiology; Animals; Behavioral neuroscience; Biological Evolution; Dominance Hierarchies; Group size; Human aggression; Individual Recognition; Individuality; Loser Effect; Mathematics; Modeling; Models, Biological; Multilevel models; Recognition (Psychology) - physiology; Self; Social behavior; Social Dominance; Social evolution; Social interaction; Winner Effect
• ISSN: 0962-8452; 1471-2954
• DOI: 10.1098/rspb.2004.2777

Winner and loser effects are defined as an increased probability of winning an aggressive interaction at time T, based on victories at time T − 1, T − 2, etc., and an increased probability of losing at time T, based on losses at time T − 1, T − 2, etc., respectively. Prior theoretical work on dominance hierarchy formation has demonstrated that when players are not capable of individual recognition, loser effects always produce a clear top-ranked (alpha) individual, but all other ranks in a group remain unclear; whereas winner effects always produce strict linear hierarchies in which the rank of each individual is clear. Paradoxically, however, when individual recognition-a phenomenon long thought to stabilize hierarchies-is possible, winner and loser effects have no impact on the probability of forming strict linear hierarchies.