Could Dogs Be the Fastest Land Animals in the World? - We Save Dogs Life

Could Dogs Be the Fastest Land Animals in the World?

TO DETERMINE THE fastest animal in the world, you must consider the nature of the race that you’re going to ask the animal to run. If you were running an air race with level flight, the champion would be the swift, which can fly at 106 miles per hour (mph) (171 kilometers per hour [kph]). Peregrine falcons are slower but can reach speeds up to 69 mph (112 kph) in direct pursuit of prey, but when diving they can reach the incredible speed of 242 mph (389 kph), which would easily allow them to catch a fleeing swift. For a water race, the sailfish blows the competition away. Its streamlined body allows it to travel up to 68 mph (109 kph), and the swordfish can do around 60 mph (97 kph).
When we’re talking about speed on land, however, the most important consideration is the distance over which the race is run. Much as in human track competitions, the shorter, sprint races will produce the fastest times. Participants in the longer races can’t sustain the speed attained in shorter runs. Looking simply at the peak speed an animal can reach, we find, as most people already know, that the fastest land animal is the cheetah, which can reach 70 mph (113 kph). Although the cheetah is an astonishingly fast runner, it can maintain that incredible velocity for only about 200–300 yards (274 meters), or less than two-tenths of a mile. Since these high speeds only allow the cat to overtake its prey within short distances, cheetahs must still rely on stealth, sneaking, and the element of surprise to get close enough to the gazelle before giving chase.
The fastest of horses is also a sprinter. It is the quarter horse, which gets its name from the fact that it was typically run in quarter-mile-long (0.4-kilometer) races. It can reach 47.5 mph (76 kph) over that distance, but it has pretty much burned out by the half-mile (0.8-kilometer) mark. Over a longer distance, horses are considerably slower than this peak value. When the thoroughbred race horse Secretariat set the Kentucky Derby speed record in 1973, he ran it at 38 mph (61 kph) over a distance of 1.5 miles (2.4 kilometers).
Humans have changed dogs so that some dogs can run much faster than most other animals. The really fast dogs are Greyhounds, Whippets, Salukis, and Afghan Hounds, which are called “sight hounds” because their job is to spot their quarry by sight and run it down. Characteristically, these dogs have a huge chest to accommodate large lungs to gulp oxygen and an oversized heart, plus a narrow waist that allows them to bend their body so that every stride carries them more than a body length.
The fastest of these dogs is the Greyhound. Greyhounds are specially designed for sustained, high-speed running. While going at full tilt, the dog’s heart rate can rise to 300–360 beats per minute. This means that the Greyhound heart can contract and refill with blood five times per second during a race, allowing oxygen to be transported at a phenomenal rate to supply the needs of the muscles. The Greyhound’s ability to reach top speed quickly is amazing. At maximum acceleration, a Greyhound can reach a speed of 45 mph (72 kph) within its first six strides from a standing start. No other land animal (except the cheetah) has that degree of acceleration.
To give you an idea of how fast a sprinter the Greyhound is, compare its performance to that of an elite human runner. When Asafa Powell set his 100-meter world record, he was running at a speed of 22.9 mph (36.9 kph) and covered that distance in 9.77 seconds. A Greyhound would complete that same race in 5.33 seconds.
However, the Greyhound is also a distance runner. Greyhounds can settle into a speed in excess of 35 mph (56 kph) and can run at that rate for distances as long as 7 miles (11 kilometers). This means that while the cheetah can win the short sprint race, in any long race the Greyhound will leave that big cat way behind, panting in the dust.
Some dogs do even better in supermarathon races. For this we need a different type of dog, though. Consider the sled dogs, particularly Siberian Huskies, like those that participate in the Iditarod. This Alaskan sled race goes from just outside Anchorage to Nome, covering a distance of 1,161 miles (1,868 kilometers). The dog teams in this race run up to 125 miles (201 kilometers) per day, often racing for up to six hours at a time, for nine to fourteen days, pulling a sled weighing over 220 pounds (100 kilograms). Furthermore, they run at full tilt in extremes of climate where the windchill can be −100°F (−73.3°C). The record for the Iditarod race is currently eight days and twenty-two hours. A sled dog’s typical racing pace averages 10–12 mph (16–19 kph), which means that in every six-hour running period he covers about 70 miles (112 kilometers). These dogs keep this up for an average of eleven days! It is hard to imagine any other animal on land that could keep up that kind of pace.

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