Why a Greyhound or a Racehorse Doesn’t “Pop a Wheelie”

The ability to gain speed quickly is crucial for survival, but there’s a limit as to how rapidly an animal can accelerate. Researchers wondered whether the “wheelie” problem experienced by cars during a drag race could be a factor in four-legged animals’ ability to speed up. They came up with a simple mathematical model… to see how fast a quadruped could accelerate without tipping over backward. The model predicts that the longer the back is in relation to the legs, the less likely a dog is to flip over and the faster it can accelerate. Then the researchers tested the model by going down to the local track, London’s Walthamstow Stadium, and video-recording individual greyhounds as they burst out of the gate in time trials. The acceleration approached–but never exceeded–the limit predicted by the model