The study examines the fitness consequences of avian personalities in a fluctuating environment, focusing on great tits (*Parus major*). Individuals differ in their exploration behavior, which is heritable and can be categorized into "fast" and "slow" explorers. The researchers measured adult survival and offspring recruitment over three years, finding that selection on these traits fluctuated annually, with opposite effects for males and females. The direction of selection varied between years, influenced by environmental conditions such as beech mast seeding. Fast explorers and slow explorers showed different survival patterns, with fast explorers performing better in some years and slow explorers in others. Offspring recruitment was also affected by parental exploration behavior, with pairs of extreme phenotypes producing more recruits in one year. The study suggests that fluctuating selection pressures due to environmental variability help maintain genetic variation in avian personalities.The study examines the fitness consequences of avian personalities in a fluctuating environment, focusing on great tits (*Parus major*). Individuals differ in their exploration behavior, which is heritable and can be categorized into "fast" and "slow" explorers. The researchers measured adult survival and offspring recruitment over three years, finding that selection on these traits fluctuated annually, with opposite effects for males and females. The direction of selection varied between years, influenced by environmental conditions such as beech mast seeding. Fast explorers and slow explorers showed different survival patterns, with fast explorers performing better in some years and slow explorers in others. Offspring recruitment was also affected by parental exploration behavior, with pairs of extreme phenotypes producing more recruits in one year. The study suggests that fluctuating selection pressures due to environmental variability help maintain genetic variation in avian personalities.