Massachusetts Wildlife Rehabilitator Practice Exam

What does crepuscular mean in relation to animal behavior?

1. Active during the day

2. Active at night

3. Active at dawn and dusk

4. Active during midday

The correct answer is: Active at dawn and dusk

The term "crepuscular" specifically refers to animals that are most active during the hours of dawn and dusk. This behavior is often an adaptation to avoid predators and to take advantage of the cooler temperatures found at these times of day, particularly in environments where temperatures can soar during midday. Crepuscular species have evolved various traits that allow them to thrive during these twilight periods, such as enhanced senses for low-light conditions. This behavior contrasts with diurnal animals, which are active during daylight, and nocturnal animals, which are active at night. The distinction helps ecologists and wildlife rehabilitators understand and interpret animal behavior in relation to their habitats and active hours.