Famous for speed, the big cats actually rely on acceleration
Structure & Motion Lab/RVC
Cheetahs may run down a track faster than any other land animal. But in the wild, the cats rarely hit top speed; it’s quick bursts of acceleration and sudden slow-downs that get the cats their dinner.
“They’re not going particularly quickly usually,” says Alan M. Wilson of the University of London Royal Veterinary College in Hatfield.
But cheetahs have got some great moves. With first-of-its-kind tracking of cheetahs on the hunt, Wilson and his colleagues show that the animals can accelerate with four times the power of world champion sprinter Usain Bolt. And the cats can put on the brakes much better than polo ponies do.
Wilson and colleagues developed collars that record both location using GPS and movement details such as acceleration. Fitted on three female and two male adult cheetahs (Acinonyx jubatus) in Botswana, the collars recorded a total of 367 running episodes, 94 of them successful hunts, the researchers report June 12 in Nature.
The collars confirmed that cheetahs are kings of speed. In one sprint, an animal hit 25.9 meters per second (58 miles per hour). Before this, Wilson says, the most reliable published test had clocked a cheetah on a straightaway at 29 m/s, faster than horses at 19 m/s, racing greyhounds at 18 m/s or Bolt’s peak 12 m/s.
Cheetahs chasing impalas often do a straight sprint or two, but especially in the final approach, the cats turn and weave as the prey dodges. Speed wouldn’t necessarily be an advantage then. A cheetah trying to maneuver at the top speed that collars recorded would need a turning radius of 52 meters, the researchers calculate.
In the zigzaggy hunts, such speed extremes weren’t common. On average, the peak speed of a hunting cheetah was 14.9 m/s, just 57 percent of the maximum that the team recorded. (Still, however, faster than Bolt.)
The collars showed that cheetahs typically slowed before maneuvering, which tightened their turns. In just one second, the researchers say, a cheetah can take three strides and brake from 16 m/s to 4 m/s. That deceleration, they calculate, shrinks its turning radius from 19.7 meters to 1.2 meters.
Cheetahs’ big, heavy claws allow them to grip the ground for such maneuvers, Wilson says. These turns and curves are demanding moves that put extra stress on their limbs. In spite of their elegant leggy looks, cheetah limb bones have comparatively large cross sections that withstand the forces of such high-speed careening after impalas.
“It would have been just fabulous to have the same collars on the impalas,” says Tim Caro of the University of California, Davis, who has long studied cheetahs. That way, researchers could study the interactions between predator and prey, perhaps shedding light on how they’ve affected each other’s evolution.
Wilson’s already on it. He’s almost finished building a kit aircraft that he and his colleagues will fit with cameras so they can take videos and collar-record all parties in cheetah chases.
The collars have plenty of possible applications, Wilson says. Creating the software and hardware has taken almost 10 years, but rather than cash in on their ingenuity the research team is sharing the technology. Earlier versions went on pigeons and polo horses, and Wilson now has collars on lions and African wild dogs.
The collars will get some fame when BBC television airs an episode of its Horizon science program featuring miniaturized cheetah collars recording the movements of domestic cats. As a gentle spoiler: Wilson reveals that the cats in an English village do less high-speed chasing across the countryside than raiding food bowls at neighbors’ houses.
A.M. Wilson et al. Locomotion dynamics of hunting in wild cheetahs. Nature. Vol. 498, June 13, 2013, p. 185. doi: 10.1038/nature12295 [Go to]
S. Milius. Built for Speed. Science News. Vol. 174, Aug. 16, 2008, p. 14 [Go to]
T. Hesman Saey. News in Brief: How the cheetah loses its spots. Science News Online. Sept. 21, 2012. [Go to]
M. Hildebrand. Further studies on locomotion of the cheetah. Journal of Mammalology. Vol. 42, Feb. 1, 1961, p. 84. [Go to]
N.C.C. Sharp. Timed running speed of the cheetah (Acinonyx jubatus). Journal of Zoology. Vol. 241, March 1997, p. 493. doi: 10.1111/j.1469-7998.1997.tb04840.x [Go to]
T.M. Caro. Cheetahs of the Serengeti Plains: Group living in an asocial species. University of Chicago Press. 1994.
Biomechanics Project. Analysis of Bolt’s 100m. [Go to]
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