The earliest suggested evidence of Columbian mammoth butchering in America (from Lovewell, Kansas) dates from 18,000 to 21,000 years ago. Paleoamericans of the Clovis culture, which arose roughly 7,000 years later, may have been the first humans to hunt mammoths extensively. These people are thought to have hunted Columbian mammoths with Clovis pointed spears which were thrown or thrust. Although Clovis points have been found with Columbian mammoth remains at several sites, archeologists disagree about whether the finds represent hunting, scavenging dead mammoths, or are coincidental. A female mammoth at the Naco-Mammoth Kill Site in Arizona, found with eight Clovis points near its skull, shoulder blade, ribs, and other bones, is considered the most convincing evidence for hunting. In modern experiments, replica spears have been able to penetrate the rib cages of African elephants with reuse causing little damage to the points.