Why Are Female Hyenas Dominant? Life in a Hyena Clan

How a hyena clan works

Spotted hyenas live in clans of a handful to more than 80 animals that share a territory and a communal den. Every clan has a strict, linear hierarchy: each hyena knows exactly who it outranks and who outranks it.

At the top sits the highest-ranking female, often called the matriarch, followed by her offspring and close female relatives. Other female family lines, or matrilines, rank below. Males born into the clan hold ranks close to their mothers’ while they are young. Adult males that have immigrated from other clans sit at the bottom, below nearly all clan-born hyenas.

Rank matters most at a carcass. High-ranking hyenas feed first and longest, while low-ranking animals are pushed aside, which is often when you hear the famous giggle explained in Why do hyenas laugh?

Is it just about size?

Female spotted hyenas are on average about 10 percent heavier than males, and they are generally more aggressive. That alone, however, does not explain the hierarchy. Rank depends far more on social support than on strength: a small but well-connected hyena can dominate a larger, isolated one.

A 2019 study of hyenas in Tanzania’s Ngorongoro Crater, by Colin Vullioud, Oliver Höner and colleagues, compared the social support available to males and females. It concluded that females dominate mainly because they stay in their birth clan surrounded by kin who back them in disputes. Immigrant males arrive alone and lack such allies. Males that stay in their birth clan with family support can hold relatively high ranks.

How cubs inherit their rank

Spotted hyena cubs are not born knowing their place, but they learn it quickly. When a cub gets into a dispute, its mother and her allies step in and help it win against anyone ranked below the mother. Over the first year or so, the cub comes to dominate all the hyenas its mother outranks. This is called maternal rank inheritance.

Daughters end up ranking just below their mother, and an unusual pattern often follows: the youngest daughter tends to outrank her older sisters, because the mother supports the newest cub most strongly. The result is a hierarchy that can stay stable over many generations.

Rank has real consequences. High-ranking females get more food, breed younger, have shorter gaps between litters and raise more surviving cubs, and they pass these advantages to their daughters.

Unusual female anatomy and hormones

Female spotted hyenas are famous for their male-like genitals. The clitoris is greatly enlarged into a so-called pseudo-penis, and the fused labia form a structure that resembles a scrotum. Females have no external vaginal opening: they urinate, mate and give birth through the pseudo-penis.

This anatomy gives females full control over mating, since a male cannot mate unless the female cooperates. It also makes birth difficult. The birth canal is long and narrow, the pseudo-penis tears during the first birth, and studies of captive hyenas found that many first-born cubs die during labor.

Hormones play a part in hyena behavior, too. Late in pregnancy, female spotted hyenas have high levels of androgens, the hormones linked to male traits, and high-ranking mothers have higher levels than low-ranking ones. Their cubs tend to be more aggressive, which may help them hold their inherited rank. The pseudo-penis itself, however, appears in the embryo largely independently of these hormones, so its origin is still debated.

Why might female dominance have evolved?

Biologists have proposed several explanations, which are not mutually exclusive:

• Competition at kills. Dozens of hyenas may crowd a single carcass. Mothers that can push others aside get more food for themselves and their cubs.
• Expensive motherhood. Hyena cubs nurse for 12–16 months or longer on milk very rich in fat and protein, and mothers do not bring food back to the den. Females need priority access to food to sustain this.
• Social support. Because females stay home and males move away, females are the ones with family allies, as the Ngorongoro study showed.
• Female choice. The pseudo-penis means males cannot force mating, which gives females control over who fathers their cubs.

How males fit in

Male spotted hyenas usually leave their birth clan at around 2–6 years of age and try to join another clan. Newcomers are low-ranking and must behave submissively, approaching females with lowered heads and bowing displays.

Over time, a male rises in the male hierarchy as older immigrants die or leave, mostly by waiting rather than fighting. Studies have found that females often prefer to mate with males that were born in, or joined, their clan after they themselves were born, which helps avoid inbreeding and may favor patient, long-staying males.

How hyena clans compare with other animal groups

Female-led societies are rare among mammals, but not unique. Elephant herds are also led by an older female, as in the African bush elephant, but elephant matriarchs lead through experience rather than aggression, and adult males live mostly apart.

The contrast with a lion pride is striking. Lionesses also form the stable core of the group, but adult males hold power at the carcass and take over prides by force, as explained in What is a group of lions called? In a hyena clan, by contrast, even a cub of a high-ranking female can push an adult immigrant male away from food.