June 22, 2012
Cheetah vs. Greyhound: Which One Is Faster?
Brett Smith for redOrbit.com
With Cheetahs going from 0 to 60 mph in around three seconds, they can easily outpace last year´s Ford Mustang, but just what propels the world´s quickest land animal to record rates?
“Cheetahs and greyhounds are known to use a rotary gallop and physically they are remarkably similar, yet there is this bewitching difference in maximum speed of almost a factor of two,” said study co-author Alan Wilson from the Royal Veterinary College of London, in a statement.
To compare the two animals, the researchers first enticed the big cats living in the ZSL Whipsnade Zoo, UK, and the Ann van Dyk Cheetah Centre, South Africa to run after bait and across force plates buried in the ground while filming the chase at 1,000 frames per second.
“Force plates are cosseted, loved pieces of equipment that people don't generally take outside of the lab and bury in the ground in the English summer,” Wilson mused.
After taking measurements of the captive big cats´ stride, footfall patterns, and force exertions–they shifted the same test procedure over to their greyhound subjects. The only exception being that the speedy dogs were filmed at a leisurely 350 frames per second.
In watching video of the two animals´ stride patterns, the team initially found that the cheetahs´ strides were slightly longer with a slightly lower frequency. However, as they shift into upper gears, the fast and furious felines increase frequency from 2.4 strides per second at 20 mph up to 3.2 strides per second at their top speed of 40 mph. In contrast, the dogs stayed at around 3.5 strides per second throughout their range.
Surprisingly, the dogs´ maximum speed was faster than the cats´ at 42.5 mph. In the wild, Wilson said cheetahs may likely reach 4 strides per second, which could explain their greater top speeds measured at around 65 mph.
The researchers also analyzed the length of time that each animal's foot remained in contact with the ground — known as the stance time. For some of the cheetah's limbs it was longer than the greyhounds, and the team suspects that this may be another factor that contributes to the wild cheetah's record performance. Wilson explained that by increasing the stance time, the animal put less strain on the animals legs and “'[with] a longer stance time the cheetah will get to the limiting load at higher speed than the greyhound.”
The captive cats most likely failed to run anywhere near record speeds because they lack motivation or have unusually sedentary lifestyle. Wilson expects to solve this problem in his future research.
“They have lived in a zoo for several generations and have never had to run to catch food,” he said. “The next stage is to try to make measurements in wild cheetahs in the hope of seeing higher speeds.”