The Buzz Log - Fastest Mammal on Earth - Yahoo! Buzz Cheetahs always win. Usain Bolt may get his share of million-dollar jackpots for being a world champ sprinter, but he's got nothing on 8-year-old Sarah. The Cincinnati Zoo's cheetah ambassador just beat the 2001 land-speed world record for mammals. A male cheetah in South Africa covered 100 meters in 6.19 seconds. Sarah didn't beat that just once, but twice: She first clocked in at 6.16 seconds and then 6.13 secondswhich, by the way, bested Bolt's August sprint by more than 3 seconds. And that's from a girl who has been in captivity pretty much her whole life.