Mods: This may quickly wander off into IMHO so feel free to move it as appropriate. However there should be a definitive answer.
I was watching a movie last night… yes I realize that movies don’t represent reality… and in it there was a horse chasing a dog on relatively flat ground. The chase scene went on for a few minutes and I kept thinking to myself that a horse would certainly run down a dog faster than that. But is that really the case?
For the sake of simplicity let’s consider a dirt road that goes on for miles. You have a standard-sized healthy German Shepherd dog, certainly not the fastest dog in the world, and a standard-sized healthy American Quarter Horse, not a thoroughbred. They both take off from a standing start.
My guess would be that the dog would take the lead initially, but that the horse would catch up with the dog and within a minute or two would leave him in the dust.
I know that dogs have evolved for long distance pursuit of prey, but in a head-to-head race it seems the body mass of a horse would outweigh the endurance of a dog.
It all depends on the distance. Dogs/wolves, being cursorial hunters will win in the long run. Can the dog change direction? If so, it’s probably agile enough to stay away from the horse.
In shorter distances, up to say a quarter mile, the horse would win.
I’m not sure what “body mass” has to do with speed advantage unless they’re sledding or something. “Length of stride” might be more of an advantage to the horse.
The table shows “measurements are for maximum speeds over approximate quarter-mile distances,” which may not address endurance.
My guess is that the horse would have the advantage, although possibly only slightly, once it gets up to full speed, but only on a straightaway. The dog would have a large advantage in cornering and maneuverability and would be able to evade with ease.
I think wolves are used to cursorial hunting of prey very much like horses.
This link says some racing dogs can overtake even the fastest Arabian horses:
This link concurs that greyhounds are faster than horses:
Almost certainly false. The Pronghorn seems to easily claim second place in the land animal speed derby - and if the speed is measured over distances greater than 100 yards, the cheetah fades rapidly leaving the pronghorn unchallenged. Various sources say this animal can do something like 40 mph for 20+ minutes.
This source says the Greyhound only manages 15th place among land animals.
Most of those sites giving speeds are useless, because they don’t specify the distance that this speed was measured.
For example, horses range from 43mi/hr for a 1/2 mile race, but drop to 36 mi/hr in a 2 mile race (based on world records). And for a long endurance race (100 miles), they are down to 11 mi/hr. So there is a major dropoff with distance & time: horses drop 10% from a 1/4 mile race to a full mile, and 5% more in the second mile.
You say this chase “went on for a few minutes”; by that time the horse would have been down to 35mi/hr or less. (Probably less if it’s a Quarter Horse as you specified; after a mile, Thoroughbreds are faster than Quarter Horses.) I don’t know how dogs do as far as speed and maintaining it over distances, so I can’t answer that. (And you specified a German Shepherd dog; I don’t think there are speed records kept on them. Possibly you could compare to greyhounds, which do have racing records. Note that greyhound races are sprints, usually only 1/3 to 1/4 mile – far less than most horse races.)
This gets even worse once you realize the quote didn’t specify land speeds. Almost any bird can get better speeds, for much longer distances, than a cheetah.
