He added that if a group from Population B then splits off and migrates, resulting in Population C, B and C stone points would then share novel characteristics that distinguish them from As, while Cs would have new qualities distinguishing them from Bs.
Buchanan and Collard believe the best explanation for the differences between Clovis points is a rapid colonization process of the Americas that involved repeated splitting of populations.
Early Paleo-Indian specialist Todd Surovell, who is an assistant professor of anthropology at the University of Wyoming, told Discovery News that he is "intrigued" by the new findings, although he thinks sharing between existing populations could explain some of the projectile point differences too.
Surovell also said there is a debate among scientists about whether other ancient groups predated the Clovis (Paleo-Indian) culture and the opening of the ice-free corridor, but he still supports most of the paper's conclusions.
"Their paper raises an interesting question," he said. "Is it possible that Clovis represents a colonizing population, but not the first population to colonize the New World? Clearly we have more work to do."
