Motley: I would guess that you don't have the speed, endurance and brawn our ancestors displayed. I sure don't.

One example, our ancestors practiced persistence hunting: "The procedure is not to spear the antelope or kudu from a distance, but to run it down in the midday heat, for about two to five hours over 25 to 35 km (16 to 22 mi) in temperatures of about 40 to 42 °C (104 to 108 °F)."  They are lots of other examples of amazing physical feats still being done by indigenous peoples that would kill the average American.