At Lovewell years ago, fossil hunters found broken-up bones of mammoths; the site has been dated to 22,000 years ago, 6,000 years older than what Waters found. A colleague of Waters and Mandel, Steven Holen, has shown through experiments that the only way those bones could have been broken was by people smacking them with large stones, to get at the marrow or to break the bone to make tools.