Diurnality

Diurnality is a form of plant and animal behavior characterized by activity during daytime, with a period of sleeping or other inactivity at night.

[5] Scientifically classifying diurnality within animals can be a challenge, apart from the obvious increased activity levels during the day time light.

Vision has been one of the most greatly affected senses from switching back and forth from diurnality to nocturnality, and this can be seen using biological and physiological analysis of rod nuclei from primate eyes.

[8] Still today, diurnality seems to be reappearing in many lineages of other animals, including small rodent mammals like the Nile grass rat and golden mantle squirrel and reptiles.

[4] Using the example of geckos, it is thought that species like Mediodactylus amictopholis that live at higher altitudes have switched to diurnality to help gain more heat through the day, and therefore conserve more energy, especially in colder seasons.

[5] Light is one of the strongest influences of the suprachiasmatic nucleus (SCN) which is part of the hypothalamus in the brain that controls the circadian rhythm in most animals.

[9] The SCN uses visual information like light to start a cascade of hormones that are released and work on many physiological and behavioural functions.

Ambient temperature has been shown to affect and even convert nocturnal animals to diurnality as it is a way for them to conserve metabolic energy.

[10][1] Nocturnal animals are often energetically challenged due to being most active in the nighttime when ambient temperatures are lower than through the day, and so they lose a lot of energy in the form of body heat.

[10] Another similar study that involved energetically challenging small mammals showed that diurnality is most beneficial when the animal has a sheltered location to rest in, reducing heat loss.

[11] For example, the baobab is pollinated by fruit bats and starts blooming in late afternoon; the flowers are dead within twenty-four hours.