Balancing food, activity and the dangers of sunlit nights

摘要: Living in northern latitudes poses challenges to the animals that live those habitats. The harsh environment provides a short breeding season where sunlit summer nights provide little reprieve from visibility predators and increased risk. In this paper, we tested activity food choice patterns of bank voles Myodes glareolus early spring season, categorized by 18 h daylight 6 h dusk every day cycle. We found territorial females showed less predictable pattern than males were most active during hours dusk. also preference forage on high carbohydrate foods at sunset, while switching over more protein fat-based diet towards sunrise. This shift is suggestive direct adaptation day-long fasts. Our results suggest sensitive mechanism between predator avoidance system light increase predation risk considerably. Bank voles, glareolus, are considered model organism ecological studies have been used for population cycles, predator-prey interactions territoriality with century published records. study, challenge two major preconceptions about these using behavioral bio-assays controlled environment. (1) diurnal rodents currently accepted bi-modal distribution months show unimodular pattern. And (2) not opportunistic foragers but vary their compensate stress an extended daytime fast further supporting nocturnal even extreme night lasts under hour.