Popular lore has it that skilled Neanderthal hunters once herded mammoths off cliffs to a rocky doom. There is one site in Jersey, a British island off of France's northern coast, where mammoth bones marked with prehistoric stone knife marks were found in broken heaps. Because Neanderthals frequented the area, researchers thought this finding meant that the Neaderthals were systematically driving the animals over the edge of cliffs for an easy kill. And this idea has spread widely, through documentaries and media stories.