The term for animals that are most active during twilight is "crepuscular." Crepuscular animals are typically active during the dawn and dusk hours, which can provide various advantages, such as avoiding predators and competing less for food. Examples of crepuscular creatures include deer, rabbits, and many species of insects. This behavior helps them take advantage of the cooler temperatures and lower light conditions during these transitional periods of the day, as well as ensuring that they can find food while minimizing their exposure to potential threats.