Another example, from the article: "there has been other signs of contacts, including bones of domesticated pigs in Germany in Stone Age hunter-gatherer settlem

Another example, from the article: "there has been other signs of contacts, including bones of domesticated pigs in Germany in Stone Age hunter-gatherer settlements. "There are trade networks that pre-date agriculture,"" Regarding the amber trade, see also http://en.wikipedia.org/wiki/Amber_Road http://en.wikipedia.org/wiki/Amber_Road .