The Insane Biology of: The Spotted Hyena

Spotted hyenas possess the strongest bite force of any carnivore relative to size, generating 1,140 PSI—40% more than lions and 15% more than grizzly bears. They are the only existing animals evolved specifically to crack bones with jaws.

Spotted hyenas maintain the most rigid hierarchy structure of any social mammal. Females dominate all males, with alpha females ruling clans. Females are 20 kilograms heavier and physically stronger than males.

Female spotted hyenas possess elongated clitorises resembling penises (pseudo-penises or peniform clitorises) and fused enlarged labia resembling scrotums. They are the only mammals lacking vaginal openings, making them unique among all hyena species.

Spotted hyena clans contain 6 to over 100 individuals—larger than wolf packs, lion prides, or orca pods. Clans defend territories up to 1,600 square kilometers. Hyenas are the only animals lions regularly flee from when outnumbered.

Spotted hyenas possess one of the richest vocal repertoires of any terrestrial mammal. Clan members use sophisticated acoustic signals to coordinate across territories spanning up to 1,600 square kilometers.

Spotted hyenas diverged from striped and brown hyenas 10 million years ago. Ancestral hyenas were smaller scavengers capable of crushing some bones but unable to take down large living prey.

Female spotted hyenas kill cubs of rivals to maintain social standing and eliminate competing bloodlines. Littermate cubs fight for nursing priority, sometimes fatally. Half of all young hyenas die before maturity.

Spotted hyena mothers provide 14 months of nursing followed by continued food provisioning until cubs reach 3-4 years old. Mothers display intense emotional distress when cubs die and fight fiercely to protect offspring despite overall clan brutality.

Spotted hyenas consume anthrax-infected carcasses and rotting putrid flesh without illness. They remain unaffected by rabies and distemper outbreaks that devastate lion and wild dog populations. High-ranking individuals maintain elevated antibody levels compared to subordinates.

Despite superficial resemblance to dogs, spotted hyenas are genetically closer to cats and even more closely related to mongooses and civets. Four hyena species exist, with spotted or laughing hyenas being the largest.

Spotted hyena clans operate as fission-fusion societies where individuals aggregate when cooperation is needed, then disperse to minimize confrontation. This social organization is rare among terrestrial carnivores and more commonly seen in marine mammals and primates.