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Travel My Hometown In L. Travel The last artists crafting a Thai royal treasure. Subscriber Exclusive Content. Why are people so dang obsessed with Mars? How viruses shape our world. The era of greyhound racing in the U. Spotted hyenas are unlike all other mammals in that the females are significantly bigger than the males and much more aggressive.
Every hyena clan is a matriarchy ruled by an alpha female. Itinerant adult males rank last, reduced to submissive outcasts begging for acceptance, food and sex. A frenzied scrum of hyenas can turn a pound adult zebra into a bloody stain on the grass in under 30 minutes. In a single feeding, an adult can gobble up to one-third of its body weight, or between 33 and 44 pounds of meat.
Dominant females have another trick for giving their cubs an aggressive advantage. A recent study by Holekamp has shown that the more powerful the female, the more testosterone her fetuses are exposed to during the final stage of pregnancy. And they already have the necessary weapons: Unlike most mammals, hyena cubs emerge with eyes open, muscles coordinated and teeth already pierced through their gums and eager to bite.
These belligerent newborns frequently fight to the death over dinner, and siblicide is commonplace. Unlike most animals, where the males duke it out and the winner gets the girl, in spotted hyena clans the females dictate the who, where and when of copulation. This is pretty handy because, in addition to the dangers lurking in her precarious birth canal, a spotted hyena suffers a few other reproductive challenges.
Her ovaries have comparatively little follicular tissue and produce relatively few eggs, and so it pays for her to be picky. Holekamp reckons the pseudo-penis allows the female to choose not just whom she mates with but, more impressively, who actually fertilizes her precious eggs by acting as a form of built-in birth control. That strangely elongated reproductive tract, with its various twists and turns, slows down sperm as they swim towards their goal.
If the hyena changes her mind about a male after mating, she simply flushes out his semen by urinating. Go, sister! I wonder whether this new image of the spotted hyena as a pioneering feminist, strutting around the savannah with a counterfeit penis, beating up on submissive males and taking control of her sexual destiny, would have been any less sacrilegious to the male bestiary authors than the original hermaphrodite myth.
This set the stage for a resolutely damning portrait of the hyena that often included grisly tales of grave robbing. However, only the brown hyena and the striped hyena are primarily scavengers.
Spotted hyenas are highly efficient predators, killing 95 percent of the food that they consume. Hunting parties are capable of bringing down aggressive animals, like water buffalo, several times their size. Such tactics are not for the faint-hearted, yet somehow hyenas have an enduring reputation for being a bunch of wimps. Field studies have found that lions actually steal more kills from spotted hyenas than vice versa.
The idea that hyenas are cowards has persisted well into the modern age. On safari one misty morning near Lake Nakuru, Kenya, I caught up with a pack of spotted hyenas hunting a zebra, their favorite prey. It was a tough watch. The hyenas were now following this semi-eviscerated beast, waiting for its inevitable collapse.
However, hyenas are not above attempting to displace lions or leopards from their kill. Hyenas are actually successful hunters, but also proficient scavengers. They have a series of calls that ranger from whoops to cackles and high pitched sounds. Each call means something different. The laughter is heard most often, and this is the sound that indicates anxiety and serves to beckon the rest of the clan to the site of a carcass. With vultures you will hear an almighty swoosh of wings as they approach an abandoned carcass.
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