Energy Conservation Hypothesis of Sleep

Predator Avoidance Hypothesis of Sleep

Species-Specific Sleep Patterns as Evolutionary Adaptations

A species of small, diurnal rodent lives in an environment with many nocturnal predators. This rodent spends most of the night sleeping in a deep, hidden burrow. From the perspective of sleep as an adaptive function, what is the most compelling explanation for this behavior?

A species of small mammal lives in an environment with numerous daytime predators and scarce food resources. This animal spends most of the daylight hours inactive and asleep in a hidden burrow, becoming active to forage for food only during the night. From an evolutionary perspective, what is the most likely primary adaptive advantage of this specific sleep-wake cycle?