Wet Sahara and the Diffusion of Agriculture

More evidence of a wet Sahara and the neolithic civilization that inhabited it.

See:

http://dsc.discovery.com/news/2008/08/14/sahara-cemetery.html

Evidence that agriculture diffused through the Mediterranean, rather than the neolithic population displacing hunters and gatherers.

See

http://www.nytimes.com/2008/08/11/science/12visuals.html?_r=1&oref=slogin

Why are these discoveries or possible discoveries important? The first is more support for the thesis that the drying up of the Sahara lakes created great devastation among the people living there, forcing the survivors to invade the Nile Valley, conquering its inhabitants and creating the beginnings of a class and state system. The latter for questioning the widely-held belief that agriculture gave rise to conquest of hunter-gatherers and that the new technology spread by a form of imperialism.