title: Costs of growing up as a subordinate sibling are passed to the next generation in blue-footed boobies.
abstract: As stresses in early development may generate costs in adult life, sibling competition and conflict in infancy are expected to diminish the reproductive value of surviving low-status members of broods and litters. We analysed delayed costs to blue-footed booby fledglings, Sula nebouxii, of junior status in the brood, which involves aggressive subordination, food deprivation and elevated corticosterone, but little or no deficit in size at fledging. In ten cohorts observed for up to 16 years, juniors showed no deficit in breeding success at any age, independent of lifespan, including in a sample of sibling pairs. Among females, juniors actually outreproduced seniors across the 16-year span. However, offspring produced by juniors in the first 3 years of life were less likely to recruit into the breeding population than offspring of seniors. Since junior fledglings survive, recruit and compete as well as seniors (shown earlier), and breed as successfully as seniors across the lifespan, it appears the delayed cost of subordination is passed to offspring, and only to those few offspring produced in the first 3 years of life. These correlational results indicate that systematic competition-related differences in developmental conditions of infant siblings can alter their reproductive value by affecting the viability of their eventual offspring.
authors.affiliation: Instituto de Ecología, Universidad Nacional Autónoma de México, Mexico. hugh@unam.mx
authors.forename: H
authors.initials: H
authors.lastname: Drummond
authors.forename: C
authors.initials: C
authors.lastname: Rodríguez
mesh_terms: D000374:Aggression / Q000502:physiology*; D000818:Animals; D001717:Birds / Q000378:metabolism / Q000502:physiology*; D001947:Breeding; D003163:Competitive Behavior / Q000502:physiology; D003345:Corticosterone / Q000378:metabolism; D005260:Female; D056084:Genetic Fitness; D008297:Male; D009425:Nesting Behavior / Q000502:physiology; D012098:Reproduction; D012930:Social Dominance; D013045:Species Specificity; D016019:Survival Analysis; D013997:Time Factors
chemical_list: D003345:Corticosterone