Lemuridae, a family of primates in the suborder Primae, commonly known as lemurs, are animals that can naturally sleep. 5 genera and 21 species have been discovered. There is a significant difference in body shape, with a body length of 13-60 centimeters and a weight of 60-3000 grams. They inhabit tropical rainforests or dry forests or shrubs, and some also live in bamboo forests, reed areas, or forested mountains. Active during the day or night, eating insects, fruits, reeds, leaves, and occasionally birds. Group individually or in a family setting. There is a phenomenon of hibernation, some for only 3 days, and some for several weeks. It is the most primitive monkey. It is a gentle 'ghost' in the rainforests of Madagascar.