The California scientist who has proposed humans reached the Americas roughly 130,000 years ago, far earlier than previously thought, defends his study against skeptics.
SAN DIEGO, CALIFORNIA, UNITED STATES (APRIL TELLEZ / SAN DIEGO NATURAL HISTORY MUSEUM) – A California scientist, who has proposed humans reached the Americas far earlier than previously thought, has defended his study against skeptics.
Researchers from the San Diego Natural History Museum have said stone tools and broken mastodon bones unearthed in the early 1990s show that humans had reached the Americas by about 130,000 years ago – until now the oldest widely accepted date for human presence in the New World was 14,000 to 15,000 years ago.
The finding would radically rewrite the understanding of human history and some scientists not involved in the study have voiced skepticism. They have suggested alternative explanations about the material excavated at a freeway construction site, suggesting the bones may have been broken recently by heavy construction equipment rather than by ancient humans.
“So when we first discovered the site, this is a tabular bed like a book laying on its side and one corner of the book was touched by the bulldozes, but the bulk of the book, so to speak, was undamaged and actually as we got into the hill that this layer extended into and under, we were up to 10-feet below original ground level, so there was no damage, no touching of the specimens by bulldozers, except for that very, again, the edge of the book, so to speak, said San Diego Natural History Museum paleontologist Tom Demere (DEM-or-ay).
While no human skeletal remains were found at the site, wear and impact marks and the way in which mastodon limb bones and molars were broken have convinced the researchers humans were responsible. They performed experiments using comparable tools on elephant bones and produced similar fracture patterns.