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How Male Antelopes Get the Girl: Feigning Fear

5 minute read
Jeffrey Kluger

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.

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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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The researchers also made recordings of three types of sounds produced by the males: a real alarm call, a false one and an unrelated grunt or snort. Playing the sounds 20 different times for 60 different females, they found a consistent set of reactions: the females ignored the random grunt but stopped in their tracks when they heard either the real snort or the fake one.

“It’s almost amusing to us,” Pangle said in a press statement. “The female hears the snort and thinks, Oops, there is a lion.” The fact that the female is so readily taken in by the ruse either means that the male is very good at disguising his motives or that, even if he’s not, the female still decides it’s not worth taking any chances. “Even if they caught on, it’s still better to be safe than sorry,” said Pangle. “The cost of missing that cue, if it is accurate, is so high.”

(See the top 10 animal stories of 2008.)

The larger implication of the study is one that a randy male topi himself would never bother to consider, but that may speak well of him all the same. Conscious deception is a trait not unheard of in the animal kingdom, but it’s a rare one. Plovers are known to fake a broken wing to lead predators away from their nest, for example, only to flap away to safety at the last moment. Knowing the truth and misrepresenting it to another individual requires what is known as a “theory of mind,” the awareness that what you know is not the same as what everyone else knows. That, in turn, implies the awareness that other creatures have minds at all — a very high-order insight and one that humans don’t fully achieve until they’re 3 years old.

Pangle cautions that it may be too early for the topi to start applying to colleges. “Intelligence is not a necessary requirement for a deceptive trait to evolve,” she tells TIME. Misrepresenting the truth will be favored in a communication system if the benefit of being fooled is greater than the cost. In other words, the male topi might have come by the trait accidentally, and for reasons it did not understand, more matings resulted. Of course, the fact that those extra matings do result means that more young topis will inherit the behavior. However the topis learned to deceive, they’re not going to unlearn it anytime soon.

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Write to Jeffrey Kluger at jeffrey.kluger@time.com