Nocturnal animals are species that are primarily active during the night and rest during the day. This behavior, known as nocturnality, is common in many creatures, including various mammals, birds, reptiles, and insects. Nocturnal animals have adaptations that help them thrive in low-light conditions, such as enhanced senses of hearing, smell, or sight (like echolocation in bats). This behavior has been well-documented by scientists today.

The concept of nocturnality was studied in depth in the 20th and 21st centuries, revealing the significant role it plays in the survival strategies of many species. This behavior allows animals to conserve energy, avoid the heat of the day, or reduce competition with diurnal creatures.

In the Quran, there is a verse that aligns with the modern understanding of nocturnal creatures:

- This verse acknowledges that some creatures rest during the night and others rest during the day. By implication, it recognizes the existence of creatures that are active at night, which was not a widely understood concept 1400 years ago. - The phrase "rests in the night" refers to animals that are active during the night and sleep during the day. Conversely, "rests in the day" refers to diurnal animals that are active during the day.