Here is an interesting lecture by Loren Cordain on the diet of Palaeolithic peoples and what they actually ate.  Don’t worry about what he says about fats.  The fat he is talking about is the fat from feedlot animals.  This is not a natural fat as grazing animals were never meant to eat grain nor be stuck in one place for a long time.  This makes their fat very unnatural  and not good for their health or ours!
He is also in the process of changing his position on good saturated fats. He used to believe they were bad but is coming round to the recognition that they are in fact healthy.
He also talks about the need for alkalinity within the Paleo Diet and how important this is.