TY - JOUR T1 - Temporal variation in fitness payoffs promotes cooperative breeding in long-tailed tits Aegithalos caudatus. JO - Am Nat PY - 2002/08/01 AU - MacColl ADC AU - Hatchwell BJ ED - DO - DOI: 10.1086/341013 VL - 160 IS - 2 SP - 186 EP - 194 Y2 - 2024/12/22 ER -