Spotted hyenas laugh and cackle to show they are anxious, afraid, or willing to submit.  A hyena might laugh when a bigger, higher-ranking hyena tries to force it away from a kill, for example.  Hyenas also growl, and they can whoop with a rising pitch that carries across long distances.  They seem to recognize the gender of other hyenas by the sound quality of their whoops, and they may even be able to identify individuals this way. 

It is the carrying power of the hyena's voice, in part, that supports an extensive society of females.  Throughout the Serengeti and Ngorongoro Crater, related females maintain a network of clans, each defending a territory and staying in close communication with other clans.

 A Female Dominated Society
Females dominate males in almost all hyena encounters, according to Anne Engh, a  Michigan State University graduate student who studies the animals.  If a male and female want the same food, or the same cool sleeping spot, the male defers.

"The youngest female can bite the legs of the oldest male, and he has to take it," says Engh, who notes that hyenas are the only mammals, other than lemurs and some humans, that form female-dominated societies.  A strict dominance hierarchy prevails, arranged beneath an alpha female. All males rank below all females, and males maintain their own separate hierarchy.  Often, the only high-ranking males in the clan are her sons. She uses her influence, as do other spotted hyena mothers, to establish her sons' ranks in the clan's pecking order.

Mating Behavior
Females will not accept mates from their own clans, so when males reach the age of two to four, they leave to join other clans.  The newest male in a clan starts with the lowest rank, the last choice of food, and the least attractive sleeping quarters.  Females tend to accept mates on the basis of  seniority.  The longer a male stays with the clan, the more likely he is to reproduce.

Some people consider spotted hyenas ugly, disliking perhaps the servile slope of their backs, or the incongruous combination of small, round ears and massive, super-muscled jaws, or the bristling mohawk ridge of fur that runs over their heads and down their backs. Their anatomy is truly bizarre, blurring the line between the sexes.

The truth about spotted hyenas may be hard to digest -- like the bones and teeth they eat along with everything else when they find a carcass or down a wildebeest. Hyenas eat virtually all of a carcass.  They are the most efficient carnivores in the world.

Because female hyenas have to compete with males for food, and because pregnant and lactating females need extra food to nurture their cubs, pregnant hyenas are extremely aggressive feeders.  As an apparent corollary, females and males maintain similar levels of the hormone testosterone, associated with aggression.  The alpha female has six times more testosterone than any other female, and significantly more than any male in the pack.  This leads to the oddest fact of all: both male and female hyenas have penises.  Their genitalia look identical until puberty, at which time the female organ develops an opening through which cubs may be both conceived and delivered.  Internally, the female's organs are entirely female.

Communal Family-raising
Spotted hyenas raise their young in communal dens shared by about 10 females.;  Males play no role in child care.  Each mother takes care of her own cubs, suckling them for about a year before weaning them.  This experience appears traumatic for yearlings, who throw "weaning tantrums" by walking around their mothers, whining and moaning, showing their teeth in fearful grimaces.

Hunting Habits
Hyenas usually forage alone or in pairs, and they can kill alone.  A 150-pound hyena can  bring down a 450-pound bull wildebeest.  Witnessing a hyena kill is not recommended for the fainthearted.  After chasing their chosen prey to exhaustion, hyenas attack the victim's belly.  The exhausted animal, usually a wildebeest, appears dazed as it succumbs to the onslaught.

Occasionally, hyenas indulge a mysterious craving for zebra by traveling miles to find them.  They form a pack for the purpose, then walk through thousands of wildebeest, who somehow know they are not at risk, until they find a zebra herd.  A group effort is needed to isolate and kill a zebra, as herds are typically protected by zebra stallions with sharp hooves and excellent fighting ability.

The spotted hyena's efficiency and ferocity equip it to survive when prey is scarce  by driving other animals away from kills, by forming packs to hunt, and by skewing meal-time aggressiveness in favor of mothers.  Perhaps some profound evolutionary purpose, as yet unclear, is served by the odd development of their reproductive organs.  The extreme adaptations seen in the behavior of spotted hyenas appear to be effective.  If left undisturbed, the spotted hyena, even more than the "striped" or "brown" hyena, will eventually outnumber all other large carnivores in Tanzania's game parks.