The Truth About Hyaenas: debunking hyaena myths
Hyaenas are misunderstood. Unless we change the way we see these amazing animals, we soon won't see them at all. Therefore here we debunk some common myths about members of the hyaena family.
Myth: Spotted hyaenas are hermaphrodites.
Reality: Hermaphrodites are animals that are simultaneously both male and female. Although there are many creatures in the animal kingdom that are true hermaphrodites, including some fish and many snails and worms, spotted hyaenas are definitely not among them. This myth undoubtedly arose when people noticed that hyaenas with large pendulous udders (indicating they were obviously females) could suddenly develop impressive phallic erections such that they also looked like males. Interestingly, although a female spotted hyaena has a uterus and ovaries internally, externally she does in fact appear to have “masculinized” genitalia. That is, the female’s clitoris is enormously elongated to form a fully erectile pseudopenis through which she urinates, copulates, and gives birth. Furthermore, her vaginal labia are folded over and filled with connective and fatty tissues to form structures that look very much like the male’s scrotal sac. These male-like external genitalia are obvious even in female spotted hyaena cubs at birth. When spotted hyaenas mate, the male inserts his erect phallus into the female’s flaccid one. The walls of the pseudopenis become relatively thin and elastic late in pregnancy, such that the female can deliver her 1 kg babies without dying in the process. Nevertheless, the posterior surface of the pseudopenis does tear when a female first gives birth, and it is ever after marked by a vertical band of pink scar tissue. Spotted hyaenas of both sexes develop phallic erections when they engage in “greeting ceremonies” with other hyaenas from whom they have been separated for a while.
Myth: It is not possible to distinguish male from female spotted hyaenas without dissecting them.
Reality: It is in fact possible to distinguish male from female spotted hyaenas when they are at least 3 months of age. Although it is virtually impossible to identify an individual’s sex based on its body size, the sex of a spotted hyaena can be distinguished based on the sexually dimorphic glans (tip) of the phallus when the phallus is erect: the glans of the female’s phallus is blunt and rather barrel-shaped whereas the male’s is pointed and has a distinct constriction immediately above the glans. Adult spotted hyaenas can also be sexed based on other morphological and behavioral cues. As adults male spotted hyaenas have distinct testes in their scrotal sacs which can be seen when a male flicks his tail, for example, to whisk away an insect. By comparison, the pseudo-scrotum of the female contains only fat and connective tissue, such that its lobes are very small in comparison to the male’s testicles. Once they start breeding, adult females usually have distinctive teats on the posterior belly, just inside the hind limbs, and these are often very easy to see. Adults can also be sexed based on their body shape; the belly of the adult male curves up in front of his hind limbs when viewed from the side whereas the belly of the adult female has no such upward curvature. Instead, the female often develops something of a ‘paunch’ where her teats protrude such that, if anything, the curvature of her posterior belly is downward. Finally, many of the behaviors exhibited by adult spotted hyaenas is decidedly sexually dimorphic. That is, males tend to act nervous when they are interacting with females (see figure below), and can often be seen tentatively stretching their fore and hind limbs over the face of a dozing female to present their ventral surface and genital region to the female for inspection. Males also can be observed pawing the ground near a sleepy female, or bowing before her and then rubbing their faces on their forelegs as they repeatedly approach and then nervously back away from the female. Male spotted hyaenas mount females from behind when mating, as in other carnivores. In fact, even sexual play-mounting during infancy is usually only exhibited by male cubs.
Myth: Hyaenas only eat carrion.
Reality: Brown and striped hyaenas do eat a fair amount of carrion but they supplement this with small vertebrate prey they catch themselves, as well as fruits and invertebrates. Aardwolves are diminutive, delicate hyaenas that feed exclusively on ants and termites. Although most people imagine spotted hyaenas to be skulking scavengers who feed on the scraps left by more glamorous predators like lions and leopards, they are in fact excellent hunters that feed mainly on large ungulates they kill themselves. An adult spotted hyaena weighs only about 60 kg yet, without help from its group-mates, it can bring down antelope weighing over three times that much, and working together with other hyaenas, it can kill ungulates as large as giraffe and African Cape buffalo. Spotted hyaenas do not use stealth when hunting as do most large felids; instead these hyaenas are endurance hunters who chase the selected prey animal over long distances until the prey is winded; then the hyaenas close in for the kill. Like most members of the dog family, spotted hyaenas kill their prey by disemboweling rather than with a cat-like “killing bite.”
Reality: At 35 kg and 45 kg, respectively, striped and brown hyaenas are too small to engage in contests over food with other large carnivores. Aardwolves do not compete for food with other large carnivores because aardwolves eat only insects. Although spotted hyaenas do sometimes steal food from smaller predators like cheetah and wild dogs, the more common scenario in most areas where they have been studied is for spotted hyaenas themselves to kill a large ungulate and then have lions steal it from them.
Myth: Hyaenas are closely related to dogs.
Reality: Although hyaenas look rather dog-like, they are more closely related to cats than to dogs, and their closest living relatives are mongooses and the fossa, a mongoose-like carnivore found only in Madagascar.
Myth: Hyaenas make good pets.
Reality: Although a few people in Africa and Asia find very young hyaenas in nature and raise them as pets, these animals generally appear to be extremely unhappy as “domestic companions” as adults, and must often be kept muzzled at all times so that they do not harm people or property. A muzzle prevents the hyaena from being able to groom itself properly. As spotted hyaenas need several years of practice to become proficient hunters, and as they are deprived of this practice when reared as pets, it is effectively a death sentence for a captive-reared hyaena to be released into the wild. In addition, pet hyaenas cannot be released for fear that they might transfer new pathogens from captive environments into the wild. Upon reaching adulthood, many "pet" hyaenas must therefore be euthanized.
Myth: Hyaenas commonly prey on livestock.
Reality: The favorite food of aardwolves is insects, especially termites which they help to control. Although many people apparently believe that aardwolves prey on young sheep, in reality they do not kill livestock as their digestive system is specialized for coping with insect prey rather than meat or bone, and most of their teeth have been reduced to mere pegs over evolutionary time. Rather than medium- or large-sized mammalian prey, brown and striped hyaenas prefer to dine on carrion, wild fruits, insects and eggs. Small livestock, particularly young animals, can be protected from brown hyaenas and jackals at night by being placed in bush enclosures. Of the four extant members of the hyaena family, only the spotted hyaena is a potential predator on livestock. In many parts of Africa, attacks on sheep, goats and cattle are most frequent during rainy periods when wild prey are widely dispersed away from water holes (e.g., Kolowski et al. 2006). Nevertheless, in most studied populations of spotted hyaenas, livestock seldom occur in the diet of these animals, as indicated by the occurrence of livestock hairs in fecal samples, so they clearly prefer wild ungulates to domestic ones. Furthermore, as with brown hyaenas, spotted hyaenas can be deterred from attacking livestock by herding domestic animals at night into sturdy corrals.
Myth: Spotted hyaenas have magical powers, and witches ride on their backs.
Reality: Although African tribal folklore abounds with myths of this sort, none of the extant hyaenas have any magical powers, nor are any of their body parts effective as aphrodisiacs.
HYAENAS ARE INTERESTING ANIMALS THAT PERFORM ESSENTIAL FUNCTIONS IN THE ECOSYSTEMS IN WHICH THEY LIVE. HYAENAS CAN OFTEN LIVE IN HARMONY WITH PEOPLE, IF WE GIVE THEM A CHANCE.