N.M. The distinctive Clovis spear points have since been found throughout the continent and, recently, in Northeastern Asia as well, affirming the origin of these nomadic hunters. Some archaeologists have identified other sites, such as the Meadowcroft rock shelter in Pennsylvania and the Topper site along the Savannah River in Georgia, that appear to be pre-Clovis. Their dates, however, have not been authenticated to everyone's satisfaction. Others have found evidence that other populations might have migrated to the continent as well. Recent studies suggest that a seafaring population worked its way down the Pacific coast, establishing villages and fishing grounds on land that is now submerged.
Some archaeologists believe that the same process occurred along the Atlantic coast as well.
Still, the dates of such events are questioned, and that is why the Cactus Hill site has assumed such importance. The McAvoys and their colleagues have produced dating evidence that might well be irrefutable, thanks in part to Conover's discovery. Paleobotanist Lucinda McWeeney of Yale, for example, identified the species of trees that were burned in the hearths. The pre-Clovis hearth contained remnants of white pine, while the Clovis hearths contained hard Southern pine. Trees in the area now are primarily hardwood hickory and oak.