By time of the emergence of modern humans (175,000 - 200,000 years ago), we had evolved the capability of running/jogging 35-50 miles per day on a near perpetual basis. An attribute Darwinism tells us wouldn't have occurred unless this ability was necessary to survive. IOW, those who couldn't keep up didn't live to mate. The one question I have about this running man theory of mine is the practical necessity of shoes or some type of foot protection to run that consistently. I seem to have found the answer in Steven Oppenhiemer's "The Real Eve" which postulates that modern humans were almost exclusively beach combers up until at least 60,000 years ago. It's a lot easier to run barefoot on soft sand than inland terrain.
He found Neanderthals and early moderns living in Middle Palaeolithic times (100,000 to 40,000 years ago) had thicker, and therefore stronger, lesser toes than those of Upper Palaeolithic people living 26,000 years ago.
Since again, Darwinism implies that physical evolution wouldn't occur unless it was necessary to survive over an extended period, the stretched dates seem logical for the inland move away from the beach for modern humans, the cold weather suggestion seems more appropriate for the neatherdhals?
No. Those who couldn't keep up missed all the best shoe sales. (or so my wife leads me to believe)