Mammoth bones bear witness to early humans in North America
The roughly 37,000-year-old remains of a female mammoth and her calf show distinct signs of butchery, providing new evidence that humans may have arrived in North America much earlier than previously thought.
Paleontologist Timothy Rowe first discovered the fossils in 2013 when a neighbor noticed something protruding from a hill on a New Mexico property owned by Rowe.
Upon closer inspection, Rowe found a tusk, a sunken mammoth skull, and other bones that appeared to be deliberately broken. He thought this was the site where two mammoths were slaughtered.
“What we have is amazing,” Rowe said in a statement. “It’s not a charismatic site with a beautiful skeleton laid out on the side. Everything is destroyed. But that’s what it’s all about.”
Rowe, a professor at the University of Texas at the Jackson School of Geosciences in Austin, is an expert in vertebrate paleontology and does not typically study mammoths or early humans. But he couldn’t help but work on the search due to the location of the find.
“I have yet to fully process the cosmic coincidence of this site appearing in my backyard,” Rowe wrote in an email.
Multiple discoveries at the site paint a picture of what happened thousands of years ago, including bone tools, evidence of a fire, bones with fractures and other signs of slaughter of animals by humans.
Long mammoth bones fashioned into disposable blades were used to break down animal carcasses before a fire melted their fat.
According to the study, fractures created by blunt force can be observed in the bones. No stone tools were at the site, but researchers found splinter knives made from bone with worn edges.
A chemical analysis of the sediments around the mammoth bones showed that the fire was sustained and contained rather than caused by a wildfire or lightning strike. There was also evidence of bones that had been pulverized as well as burnt remains of small animals including birds, fish, rodents and lizards.
The research team used CT scans to analyze the bones at the site, finding puncture wounds that may have been used to drain fat from the ribs and vertebrae. The humans who slaughtered the mammoths were thorough, Rowe said.
“I’ve excavated dinosaurs that have been salvaged, but the pattern of disarticulation and bone breakage due to human slaughter was unlike anything I had seen,” Rowe said.
The most startling detail about the site is that it’s in New Mexico – and earlier evidence has suggested humans weren’t there until tens of thousands of years later.
Trace the first steps of man
Collagen taken from mammoth bones helped researchers determine that the animals were slaughtered at the site between 36,250 and 38,900 years ago. This age range makes the New Mexico site one of the oldest created by ancient humans in North America, researchers said.
Scientists have debated for years when the first humans arrived in North America.
“Humans have been in the Americas for more than twice as long as archaeologists have maintained for many years,” Rowe said. “This site indicates that humans reached worldwide distribution much earlier than previously thought.”
The position of the site, which is well inland in western North America, suggests that the first humans arrived well before 37,000 years ago, according to the study. These early humans probably traveled over land or along coastal routes.
Rowe said he then wanted to sample the site to look for signs of ancient DNA.
Collins was not involved in the study. He conducted research at the Gault Archaeological Site, which contains both Clovis and pre-Clovis artifacts, near Austin, Texas.
“I think the deeper significance of the early human achievement of global distribution is an important new question to explore,” Rowe said. “Our new techniques have provided nuanced evidence of a human presence in the archaeological record, and I suspect there are other sites of comparable age or even older that go unrecognized.”