Bullfrogs are known for their ability to go long periods without sleep. In laboratory studies, they have been observed staying awake for weeks at a time.
Some species of sharks, such as the great white shark, exhibit a type of sleep known as unihemispheric slow-wave sleep. This means that only one hemisphere of their brain sleeps at a time, allowing them to remain partially conscious and responsive to their surroundings.
Elephants in the wild sleep for only a few hours each day, and their sleep is often characterized by short periods of deep sleep while standing.
Giraffes have short bouts of sleep, lasting only a few minutes at a time. They often sleep while lying down, but they can also sleep while standing.
Giant pandas have a diet mainly consisting of bamboo, which has low nutritional value. To compensate for this, they spend a significant portion of their day eating and may reduce their sleep to as little as two to four hours a day.
Horses are known for having short periods of REM (rapid eye movement) sleep while standing. They also have the ability to lock their joints to support their weight while dozing.
These birds are known for their incredible flying abilities and spend most of their lives in the air. During migration, some alpine swifts have been observed flying continuously for up to six months without landing.
Certain ant species, such as the bull ant, can go for extended periods without sleep. Worker ants in a colony take turns resting, ensuring that there is always a group of active ants to attend to the needs of the colony.