Behavioural Processes, 12 (1986) l-22 Elsevier DIVISION OF PARENTAL CARE AND REPRODUCTIVE SUCCESS IN THE ZEBRA FINCH (TAENIOPYGIA GUTTATA). ---------- ----- VERONIOUE ANNIE DELESALLE Biology Department, MC Gill University, Montreal, Quebec, H3A lB1, Canada. Present Address: Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721, USA. (Accepted 21 March 1985) ABSTRACT Delesalle, V.A., 1986. Division of parental care and reproductive success in the Zebra finch (Taenioel@a guttata). Behav. ------ Processes, 12: l-22. Variation in reproductive success among pairs of Zebra finches (Taenioeyea guttata), _--_ bred in captivity under time- rather than energy-limited conditions, arose primarily because of differences in number of clutches per reproductive bout. Division of parental care between mates during the time-constrained incubation phase, rather than the fledging phase, affected their fitness and future behavior. Pairs where the males assumed a greater fraction of the pooled incubation time were more likely to breed together again than pairs where males did not share in this activity as equally. In addition, males remated with familiar mates increased their time investment in incubation. INTRODUCTION In species with biparental care, if individuals vary in the quantity and quality of their parental behaviors, the division of parental duties (or degree of behavioral complementarity) between mates may affect a pair's reproductive success and may be a component of mate choice (Burley and Moran, 1979; Erickson, 1978; Trivers, 1972). For example, a bird that is a good incubator but not an efficient forager should have a greater reproductive success when paired with an individual that is good at feeding the offspring but not necessarily good at incubating. Division of labor is necessary when two or more parental tasks must be 0376-6357/86/$03.50 0 1986 Elsevier Science Publishers B.V. (Biomedical Division)