It's a commonly known fact that the cheetah (Acinonyx jubatus) is the fastest of the land animals (according to Wikipedia, it can reach speeds between 70 and 75 miles per hour). Has this always been the case? Are there any extinct animals that may have exceeded its speed?
I realize that you can't exactly put an extinct animal in a race and measure its speed, but can't an animal's possible speed be inferred based on its skeletal structure and analogies with living, related species?
I'd like to know what the calculated running speeds for the following extinct animals are, if such data exists: The American "cheetahs" (Miracinonyx inexpectatus and M. trumani), and an extinct, running hyena (Chasmaporthetes ossifragus).
Any other fast animals you can suggest would be appreciated (such as, perhaps, dinosaurs).