Hyenas, especially spotted hyenas, are known for killing as much as 95% of the animals they eat, and for driving off leopards or lionesses from their kills, although they have long been regarded as being cowardly scavengers. Hyenas are primarily nocturnal animals, but sometimes venture from their lairs in the early-morning hours. With the exception of the highly social spotted hyena, hyenas are generally not gregarious animals, though they may live in family groups and congregate at kills. Hyenas first arose in Eurasia during the Miocene period from viverrid-like ancestors, and soon became well known as being of two distinct types: the lightly built dog-like hyenas and the robust bone-crushing hyenas. Although the dog-like hyenas thrived 15 million years ago (with one taxon having colonised North America), they became extinct after a change in climate along with the arrival of canids into Eurasia. Of the dog-like hyena lineage, only the insectivorous aardwolf survived, while the bone-crushing hyenas (whose extant spotted, brown and striped hyenas) became the undisputed top scavengers of Eurasia and Africa. Hyenas feature prominently in the folklore and mythology of human cultures with which they are sympatric. Hyenas are commonly viewed as frightening and worthy of contempt, and are associated with witchcraft, because their body parts are used as ingredients in traditional medicine. In some cultures, hyenas are thought to influence people’s spirits, rob graves, and steal livestock and children.Hyenas, especially spotted hyenas, are known for killing as much as 95% of the animals they eat, and for driving off leopards or lionesses from their kills, although they have long been regarded as being cowardly scavengers. Hyenas are primarily nocturnal animals, but sometimes venture from their lairs in the early-morning hours. With the exception of the highly social spotted hyena, hyenas are generally not gregarious animals, though they may live in family groups and congregate at kills. Hyenas first arose in Eurasia during the Miocene period from viverrid-like ancestors, and soon became well known as being of two distinct types: the lightly built dog-like hyenas and the robust bone-crushing hyenas. Although the dog-like hyenas thrived 15 million years ago (with one taxon having colonised North America), they became extinct after a change in climate along with the arrival of canids into Eurasia. Of the dog-like hyena lineage, only the insectivorous aardwolf survived, while the bone-crushing hyenas (whose extant spotted, brown and striped hyenas) became the undisputed top scavengers of Eurasia and Africa. Hyenas feature prominently in the folklore and mythology of human cultures with which they are sympatric. Hyenas are commonly viewed as frightening and worthy of contempt, and are associated with witchcraft, because their body parts are used as ingredients in traditional medicine. In some cultures, hyenas are thought to influence people’s spirits, rob graves, and steal livestock and children.