Worldwide, too little iodine in the diet is the most common cause of hypothyroidism. In countries with enough iodine in the diet, the most common cause of hypothyroidism is the autoimmune condition Hashimoto's thyroiditis.
The pronghorn is the second fastest land mammal in the world, after the cheetah. It can attain speeds of over 53 miles (86 kilometers) per hour. Size relative to a 6-ft (2-m) man: Fleet-footed pronghorns are among the speediest animals in North America. They can run at more than 53 miles (86 kilometers) an hour, leaving pursuing coyotes and bobcats in the dust.
Racehorses can gallop up to 40 mph. Sometimes faster. Some horses (mainly Saddlebreds) can do a rack up to 20 mph. We clocked my Spotted Saddle Horse gelding's fastest gait at 16 mph. They can definately go faster than 25mph!est Answer: â¦ the thoroughbred can run â¦ a mile (1.6 kilometers) in about 1 and 1/2 minutes. The American Quarter Horse is the king of speed.