Learning has not been linear for human beings. Advancement can be different from one place to another. It is now known from DNA analysis of 5,000 year old skeletons in a French cave that women did not travel into western Europe. Mitochondrial DNA is passed down only from the mother which shows that European women had local ancestry. On the other hand the Y chromosome passed down through males shows movement of males into new European regions. Knowledge of farming came into new areas when the males moved in and mated with local females. Analysis of DNA from 29 skeletons found in France, highlighted this difference between the mitochondrial DNA and Y chromosome. Males had moved from the Mediterranean to western Europe. Most of the males in the 29 skeleton group were related, so when the males arrived they stayed on the land with their new hunter gatherer wives. The southern males had a problem: they did not have the lactose tolerant gene of central Europeans. They had to drink f...