How Male Antelopes Get the Girl: Feigning Fear

Male animals hoping to mate (which is to say pretty much all male animals, pretty much all of the time) long ago learned that displaying strength, courage and fitness was the best way to attract the ladies. It's a rare male that tries cowardice as a strategy, but a study that will be published in an upcoming edition of the American Naturalist reports that the topi, a midsize antelope with a range across sub-Saharan Africa, has found a way to make looking afraid pay.

Male topis face a lot of competition when breeding season arrives. Females are in heat for just a single day out of the year, sometime in February or March. That's not much time for romance, but the hopeful mothers make the most of it, visiting the territory of an average of four males and notching an average of 11 mating sessions divided up among them. Once a female is on a male's turf, he would just as soon hope she not leave, since the longer she lingers, the more mating opportunities he has and the fewer chances the other males get before the 24-hr. window closes again. Smart males have figured out a way to rig the game. (See the top 10 animal stories of 2009.)

When a topi spots a predator — usually a lion, cheetah, leopard, hyena or human — it emits a characteristic alarm snort. The snort is not necessarily intended for other topis, since the animals will do it when they're entirely alone. Rather, it's meant as a signal to the predator, informing it that it's been spotted and has lost the element of surprise. The hunters will typically go off in search of a less-observant target.

During mating season, male topis play loose with the alarm snort. When a female on their territory is preparing to leave, the male will observe where she is headed, look straight in that direction and then snort. The female will stop, assuming that somewhere out there is someone not nice, and before she decides there's no danger after all, the male will grab one more mating.

Zoologist Jakob Bro Jorgensen of the University of Liverpool was the first to observe this cunning — and decidedly dishonest — behavior, and he and biologist Wiline Pangle at Ohio State University teamed up to confirm it with a controlled study. From 2005 to 2009, the pair logged 274 hours of observation time, during which they tracked 74 female topis in estrus as they visited the territories of various males. They also observed the males when the females weren't around. On the whole, the males were good at spotting predators and almost never emitted the false snort when they were alone, reserving it exclusively for when females were present. The females, in turn, almost always fell for it.

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