Figure 2.

Breeding success of primary and secondary (with and without male assistance) female pied flycatchers as measured by the number of grandoffspring fledged during the lifetime of their recruits. Columns depict the mean (±s.e.) difference in number of grandoffspring as compared to simultaneous monogamous broods, i.e. broods with the same laying date. p-values are given for each brood category as a comparison to the breeding performance of monogamous broods (see table 2).