Want to know the route humans took when they first migrated from Africa into Europe? Seems that they might have marked the path. Not like Hansel and Gretel, who consciously left bread crumbs. Ancient humans ate as they trekked. And they appear to have chucked aside the packaging for some of their slimy sustenance: snails. Conventional wisdom has been that humans initially travelled from Africa to the Near East, then up around the Mediterranean through Lebanon before heading into Europe some 40 to 50,000 years ago. But recently, some scientists have theorized that humans made it to Europe first and then headed east. Now there's more support for the old view that humans traveled through the Levant on the way to Europe-in the form of the shells of edible marine snails. The study is in the Proceedings of the National Academy of Sciences. Researchers evaluated shells from an archeological site dated to the Upper pileolythic in Lebanon.