Which animal has the best stamina over a long distance?

Humans. Over a marathon distance in heat, a trained person will beat a horse, and there is an annual race in Wales that has been run since 1980 to test exactly that - man against horse over 22 miles, which humans have now won twice. Almost no other animal can keep running for hours.

The reason is sweating. Most mammals shed heat by panting, which cannot be done efficiently while galloping because the breathing is locked to the stride. We sweat over a nearly hairless body, which cools far more effectively and works at any speed. Add an upright frame, a spring-loaded Achilles tendon, a large gluteus maximus for stabilising the trunk, and the nuchal ligament that stops the head nodding, and you have an animal built for exactly this.

The behaviour that goes with it is persistence hunting: not outrunning prey but following it at a steady pace until it overheats and collapses. It is still practised by a handful of groups, and it fits the anatomy so well that many researchers think endurance running is a large part of why the human body has the shape it does.