[Modernman]

Then what about camels, horses and in general all beast of burden? ALL are covered in fur and all are capable of extreme work in extreme weather. Mules in the south are capable of extraordinary work.

Camels are a special case- they've evolved a way to store water in their humps. That helps them stay cool. However, camels are not long-distance runners. They're walkers. Outside of the very extreme ecological niche that camels inhabit, humans have them beat hands down when it comes to endurance. Probably part of the reason camels have not lost their fur is because nights in the desert can be deadly cold. A naked animal can die of exposure.

Over the long-run, a man can outrun and hunt down a horse. Same thing with a mule. There are very few animals on the planet with more endurance than a human.

[jrestrepo]

Sorry, the argument is neither convincing nor logical, for me. The running argument requires the assumption that we went from four legs to two legs (unique in the entire world) and the reason we went to two legs is because we would be good at running and efficient at it. All of this requires that the end point is known. Just like the article I read about the human eye. They eyed had two know it's purpose before it started evolving.