Note the gray hair and male pattern baldness. Homo Erectus' era no doubt coincided with emergence of social structures enabled by development of stone tools, weapons, and fire.
These things increased protein levels in the diet tremendously, and fire better protected them from the elements. Naturally, mortality rates dropped, populations increased and, since less time had to be devoted to food gathering, more leisure time was available to devote to developing social roles arising around the campfire.
So why the thick skulls? Probably from these guys beating their heads against cave walls as they dealt with more mouths to feed and women complaining about them leaving their tools lying around.
[ This Message was edited by: expatriate on 2004-02-18 23:40 ]
Just think if we had heads like that today, there would be no need for jack hammers. Just walk outside, slam your head against the concrete for awhile, pull up the broken rubble then call in the cement truck. Presto new drive way!
Would have completely changed warfare in the middle ages too. Trebuchets? Onagers? Bah, just need a legion of men to slam their collective heads against the castle walls.
In the winter months, when the tempurature drops well below freezing, it gets harder to stay warm enough to be comfortable. Yes, wool socks are better than cotton but; battery powered heated socks are even better. And yet our feet end up cold at some point anyways. When we are hunting we are usally trying to be as still as possible, for as long as possible. The problem is, when we aren't moving, our blood circulation slows down. We especially lose...