Suzi Eszterhas / Spotted Hyena (Crocuta crocuta) adult female yawning at den, Masai Mara National Reserve, Kenya

Mitsuaki Iwago / Spotted Hyena (Crocuta crocuta) laughing, Serengeti

Christophe Courteau / Spotted Hyaena (Crocutta crocutta) enjoying a mud bath at waterhole, Okavango Delta, Botswana

Mary McDonald / Spotted / Laughing Hyena (Crocuta crocuta) female nursing pups, Upper Mara, Masai Mara Game Reserve, Kenya

Hermann Brehm / Spotted hyaena 'laughing' {Crocuta crocuta} Kenya