Effects of parental age at conception on offspring life history trajectories in a long-lived bird

Parental age at conception can have both short- and long-term consequences on the health, survival, and reproduction of their offspring. To date, most of our knowledge comes from laboratory studies, which consider the effects of maternal age and a “snapshot” of the life history trajectory of the offspring. Here, we use a multigenerational demographic dataset in a free-living, long-lived (median lifespan is 7 years old) bird, the Alpine swift (Tachymarptis melba), to investigate the effects of maternal and paternal age on offspring traits, from nestling to adulthood, and considering all major life history traits, from growth and age at first reproduction to reproductive success and lifespan. Parental age affected offspring phenotype before fledging and lifespan, but differently so for sons and daughters. Offspring from old-age mothers (≥ 11 years old) and fathers (≥ 9 years old) were bigger and less infested by ectoparasites before fledging, except sons from old-age fathers that show no ..., , # Data from: Effects of parental age at conception on offspring life history trajectories in a long-lived bird Dataset DOI: [10.5061/dryad.1c59zw48k](10.5061/dryad.1c59zw48k) ## Description of the data and file structure Dataset on Alpine swift life history traits at adulthood (age at first reproduction, lifespan, lifetime reproductive success) and phenotype at fledging (mass, size, ectoparasite load) associated with the article entitled \"*Effects of parental age at conception on offspring life history trajectories in a long-lived bird*\" by Moullec H., Berger V., Meier C., Reichert S. and Bize P., published in *Evolution*. ### Files and variables #### File: Evolution_AFR_swift_08.2025.xlsx **Description:** Dataset: parental age effect at conception on offspring age at first reproduction ##### Variables * ring: offspring ID * mother: mother ID * father: father ID * year_birth: year of birth of the offspring/year when the data were collected * colony: city where the data have been...,