Crepuscular in the context of Matutinal

The lion (Panthera leo) is a large cat of the genus Panthera, currently ranging only in Sub-Saharan Africa and India. It has a muscular, broad-chested body; a short, rounded head; round ears; and a dark, hairy tuft at the tip of its tail. It is sexually dimorphic; adult male lions are larger than females and have a more prominent mane that usually obscures the ears and extends to the shoulders.

The lion inhabits grasslands, savannahs, and shrublands. It is an apex and keystone predator, preying mostly on medium-sized and large ungulates. It is usually more diurnal than other wild cats, but when persecuted, it adapts to being active at night and at twilight. It is a social species, forming groups called prides. A lion pride consists of related females and cubs, and a few or one adult male who is unrelated to the females. Groups of female lions usually hunt together. Adult males often compete to keep or gain that membership in the pride.

Diurnality is a form of plant and animal behavior characterized by activity during daytime, with a period of sleeping or other inactivity at night. The common adjective used for daytime activity is "diurnal". The timing of activity by an animal depends on a variety of environmental factors such as the temperature, the ability to gather food by sight, the risk of predation, and the time of year. Diurnality is a cycle of activity within a 24-hour period; cyclic activities called circadian rhythms are endogenous cycles not dependent on external cues or environmental factors except for a zeitgeber. Animals active during twilight are crepuscular, those active during the night are nocturnal and animals active at sporadic times during both night and day are cathemeral.

The cat (Felis catus), also referred to as the domestic cat, is a small carnivorous mammal. It is an obligate carnivore, requiring a predominantly meat-based diet. Its retractable claws are adapted to killing small prey species such as mice and rats. It has a strong, flexible body, quick reflexes, and sharp teeth, and its night vision and sense of smell are well developed. It is a social species, but a solitary hunter and a crepuscular predator.Cat communication includes meowing, purring, trilling, hissing, growling, grunting, and body language. It can hear sounds too faint or too high in frequency for human ears, such as those made by small mammals. It secretes and perceives pheromones. Cat intelligence is evident in its ability to adapt, learn through observation, and solve problems. Female domestic cats can have kittens from spring to late autumn in temperate zones and throughout the year in equatorial regions, with litter sizes often ranging from two to five kittens.

The domestic cat is the only domesticated species of the family Felidae. Advances in archaeology and genetics have shown that the domestication of the cat started in the Near East around 7500 BCE. Today, the domestic cat occurs across the globe and is valued by humans for companionship and its ability to kill vermin. It is commonly kept as a pet, working cat, and pedigreed cat shown at cat fancy events. Out of the estimated 600 million domestic cats worldwide, 400 million reside in Asia, including 58 million in China. The United States leads in cat ownership with 73.8 million cats, followed by the United Kingdom with approximately 10.9 million cats. It also ranges freely as a feral cat, avoiding human contact. Pet abandonment contributes to increasing of the global feral cat population, which has driven the decline of bird, mammal, and reptile species. Population control includes spaying and neutering.

Felidae (/ˈfiːləˌdiː/ FEE-lə-dee) is the family of mammals in the order Carnivora colloquially referred to as cats. A member of this family is also called a felid (/ˈfiːlɪd, -ləd/ FEE-lid, -⁠ləd).

The 41 extant Felidae species exhibit the greatest diversity in fur patterns of all terrestrial carnivores. Cats have retractile claws, slender muscular bodies and strong flexible forelimbs. Their teeth and facial muscles allow for a powerful bite. They are all obligate carnivores, and most are solitary predators ambushing or stalking their prey. Wild cats occur in Africa, Europe, Asia and the Americas. Some wild cat species are adapted to forest and savanna habitats, some to arid environments, and a few also to wetlands and mountainous terrain. Their activity patterns range from nocturnal and crepuscular to diurnal, depending on their preferred prey species.

A feral cat or stray cat is an unowned domestic cat (Felis catus) that lives outdoors and avoids human contact; it does not allow itself to be handled or touched, and usually remains hidden from humans. Feral cats may breed over dozens of generations and become a local apex predator in urban, savannah and bushland environments, especially on islands where native animals did not evolve alongside predators. Some feral cats may become more comfortable with people who regularly feed them, but even with long-term attempts at socialization, they usually remain aloof and are most active after dusk. Of the 700 million cats in the world, an estimated 480 million are feral.

Feral cats are devastating to wildlife, and conservation biologists consider them to be one of the worst invasive species on Earth. They are included in the list of the world's 100 worst invasive alien species. Attempts to control feral cat populations are widespread but generally of greatest impact within purpose-fenced reserves.

Moths are a group of insects that includes all members of the order Lepidoptera that are not butterflies. They were previously classified as suborder Heterocera, but the group is paraphyletic with respect to butterflies (suborder Rhopalocera) and neither subordinate taxon is used in modern classifications. Moths make up the vast majority of the order. There are approximately 160,000 species of moth, many of which have yet to be described. Most species of moth are nocturnal, although there are also crepuscular and diurnal species.

Cathemerality, sometimes called metaturnality, is an organismal activity pattern of irregular intervals during the day or night in which food is acquired, socializing with other organisms occurs, and any other activities necessary for livelihood are undertaken. This activity differs from the generally monophasic pattern (sleeping once per day) of nocturnal and diurnal species as it is polyphasic (sleeping 4-6 times per day) and is approximately evenly distributed throughout the 24-hour cycle.

Many animals do not fit the traditional definitions of being strictly nocturnal, diurnal, or crepuscular, often driven by factors that include the availability of food, predation pressure, and variable ambient temperature. Although cathemerality is not as widely observed in individual species as diurnality or nocturnality, this activity pattern is seen across the mammal taxa, such as in lions, coyotes, and lemurs.

Hamsters are rodents (order Rodentia) belonging to the subfamily Cricetinae, which contains 19 species classified in seven genera. They have become established as popular small pets. The best-known species of hamster is the golden or Syrian hamster (Mesocricetus auratus), which is the type most commonly kept as a pet. Other hamster species commonly kept as pets are the three species of dwarf hamster, Campbell's dwarf hamster (Phodopus campbelli), the winter white dwarf hamster (Phodopus sungorus) and the Roborovski hamster (Phodopus roborovskii), and the less common Chinese hamster (Cricetulus griseus).

Hamsters feed primarily on seeds, fruits, vegetation, and occasionally burrowing insects. In the wild, they are crepuscular: they forage during the twilight hours. In captivity, however, they are known to live a conventionally nocturnal lifestyle, waking around sundown to feed and exercise. Physically, they are stout-bodied with distinguishing features that include elongated cheek pouches extending to their shoulders, which they use to carry food back to their burrows, as well as a short tail and fur-covered feet.

Tortoises (/ˈtɔːrtəs.ɪz/ TOR-təs-iz) are reptiles of the family Testudinidae of the order Testudines (Latin for "tortoise"). Like other testudines, tortoises have a shell to protect from predation and other threats. The shell in tortoises is generally hard, and like other members of the suborder Cryptodira, they retract their necks and heads directly backward into the shell to protect them.

Tortoises can vary in size with some species, such as the Galápagos giant tortoise, growing to more than 1.2 metres (3.9 ft) in length, whereas others like the speckled Cape tortoise have shells that measure only 6.8 centimetres (2.7 in) long. Several lineages of tortoises have independently evolved very large body sizes in excess of 100 kilograms (220 lb), including the Galapagos giant tortoise and the Aldabra giant tortoise. They are usually diurnal animals with tendencies to be crepuscular depending on the ambient temperatures. They are generally reclusive animals. Tortoises are the longest-living land animals in the world, although the longest-living species of tortoise is a matter of debate. Galápagos tortoises are noted to live over 150 years, but an Aldabra giant tortoise named Adwaita may have lived an estimated 255 years. In general, most tortoise species can live 80–150 years. Tortoises are typically slow-moving.

Nightjars are medium-sized nocturnal or crepuscular birds in the family Caprimulgidae /ˌkæprɪˈmʌldʒɪdiː/ and order Caprimulgiformes, characterised by long wings, short legs, and very short bills. They are sometimes called bugeaters, their primary source of food being insects. Some New World species are called nighthawks. The English word nightjar originally referred to the European nightjar.

Nightjars are found all around the world, with the exception of Antarctica, and certain island groups such as the Seychelles. They can be found in a variety of habitats, most commonly the open country with some vegetation. They usually nest on the ground, with a habit of resting and roosting on roads.

The Lampyridae are a family of elateroid beetles with more than 2,400 described species, many of which are light-emitting. They are soft-bodied beetles commonly called fireflies, lightning bugs, or glowworms for their conspicuous production of light, mainly during twilight, to attract mates. The type species is Lampyris noctiluca, the common glow-worm of Europe. Light production in the Lampyridae is thought to have originated as a warning signal that the larvae were distasteful. This ability to create light was then co-opted as a mating signal and, in a further development, adult female fireflies of the genus Photuris mimic the flash pattern of the Photinus beetle to trap their males as prey.

Fireflies are found in temperate and tropical climates. Many live in marshes or in wet, wooded areas where their larvae have abundant sources of food. Although all fireflies nominally glow as larvae, only some species produce light in their adult stage, and the location of the light organ varies among species and between sexes of the same species. Fireflies have attracted human attention since classical antiquity; their presence has been taken to signify a wide variety of conditions in different cultures and is especially appreciated aesthetically in Japan, where parks are set aside for this specific purpose.

Crepuscular rays, sometimes colloquially referred to as god rays, are sunbeams that originate when the Sun appears to be just above or below a layer of clouds, during the twilight period. Crepuscular rays are noticeable when the contrast between light and dark is most obvious. Crepuscular comes from the Latin word crepusculum, meaning "twilight". Crepuscular rays usually appear orange because the path through the atmosphere at dawn and dusk passes through up to 40 times as much air as rays from a high Sun at noon. Particles in the air scatter short-wavelength light (blue and green) through Rayleigh scattering much more strongly than longer-wavelength yellow and red light.

Crepuscular rays appear as divergent beams emanating from a distant source, in spite of the rays from the Sun being parallel when they arrive, because of perspective. The point from which the divergent rays appear to emerge from is really a vanishing point for parallel rays of sunlight.

The northern hawk-owl (Surnia ulula), or northern hawk owl, is a medium-sized true owl of the northern latitudes. It is non-migratory and usually stays within its breeding range, though it sometimes irrupts southward. It is one of the few owls that is not strictly nocturnal nor crepuscular, often being active during the day. This is the only living species in the genus Surnia of the family Strigidae, the "typical" owls (as opposed to barn owls, Tytonidae). The species is sometimes called simply the hawk owl; however, many species of owls in the genus Ninox are also called "hawk owls".