DOI: 10.5061/dryad.517c56h
title: Data from: Individual dispersal decisions in a cooperative breeder: ecological constraints, the benefits of philopatry, and the social queue for dominance

description: 1. Delayed dispersal is a key step in the evolution of familial animal
 societies and cooperative breeding. However, no consensus has been reached
 on the ecological and social circumstances driving delayed dispersal. 2.
 Here we test predictions from the ecological constraints and benefits of
 philopatry hypotheses as well as the recently-proposed dual benefits
 hypothesis to better understand the evolution of group-living and
 cooperative breeding. Furthermore, we consider how individual social
 circumstances within groups affect dispersal decisions. 3. We examine 11
 years of life-history information on a wild population of cooperatively
 breeding southern pied babblers (Turdoides bicolor). We investigate the
 effects of ecological conditions, natal-group membership and individual
 social context on male and female dispersal delays, disperser survival and
 acquisition of dominance. 4. Female dispersal decisions are generally
 unconstrained by ecological or social circumstances. In contrast, males
 disperse in response to relaxed ecological constraints, decreases in
 nepotistic tolerance, or when low social rank in the queue for dominance
 decreases their likelihood of gaining a dominant breeding position. Early
 dispersal by end-of-queue males often leads to a head-of-queue subordinate
 position in a non-natal group, thereby increasing access to dominant
 breeding positions. However, males and females remaining in natal groups
 gain benefits of philopatry via increased survival and, for head-of-queue
 males, very high likelihood of acquisition of a breeding position. 5.
 Overall, predictions from the dual benefits hypothesis best describe these
 results, while some predictions from each of the ecological constraints
 and benefits of philopatry hypotheses were supported. The benefits of
 living and working together (collective action benefits) in large stable
 groups are of central importance in shaping dispersal delays in southern
 pied babbler societies. In addition, position in the subordinate social
 queue for dominance is key in determining access to reproduction,
 particularly for males. This research highlights the importance of
 considering the costs and benefits of individual social circumstances in
 dispersal decisions and illustrates how the dual benefits hypothesis
 offers new perspectives in understanding delayed dispersal.
description: age at acquired
 dominanceData used for
 investigation of age at dominance acquisition from natal and non-natal
 groups.age
 at dominance.csvsubordinate
 breedingData used to investigate
 if subordinates are more likely to breed in the natal
 group.femalesData used to investigate likelihood of acquisition of dominance for females in natal and non-natal groups and at the head or end of queues.front of queueData used for investigation of the likelihood of acquisition of dominance by males and females at the head of dominance queues in natal and non-natal groups.male dispersalData for analysis of factors affecting timing of male dispersalfemale dispersalData for analysis of factors affecting timing of female dispersal.sub3Data for analysis of subordinate survival according to life history stage and sex using MARK.