Baylor University’s Institute of Archaeology Casts Doubts on Early Humans in California

February 8, 2018

Baylor researchers urge caution in interpreting findings of previous Nature article

Media contact: Tonya B. Hudson, (254) 710-4656
Follow Baylor Media Communications on Twitter: @BaylorUMedia

WACO, Texas (Feb. 8, 2018) – When did prehistoric humans first arrive in North America?

In an article published today in the premier journal Nature, “Contesting Early Archaeology in California,” researchers from Baylor University’s Institute of Archaeology and the Departments of Anthropology and Geosciences challenge a widely reported claim for the earliest archaeological evidence of the peopling of the Americas.

The article in question by Holen et al., “A 130,000-year-old Archaeological site in Southern California, USA,” published in Nature in April 2017, contends that the record of broken bones and stones at the Cerutti Mastodon site, a paleontological assemblage discovered near San Diego, indicates that humans had arrived in the Americas more than 110,000 years earlier than is currently believed.

Joseph V. Ferraro, Ph.D., associate professor of anthropology in Baylor’s College of Arts & Sciences and director of the Institute of Archaeology, and his fellow researchers urge caution in interpreting the Cerutti finds. “We argue that the purported human-induced damage to the mastodon’s bones are actually common features of the paleontological record. Some of these damage morphologies are present in dinosaur remains and are not unique indicators of human activities,” the researchers said.

To bolster their arguments, the Baylor researchers compared bone damage from Cerutti Mastodon Site with that from several non-archaeological mammoth death sites, including the 66,000-year-old Waco Mammoth National Monument in Texas.

“The Waco mammoths represent a mass-death assemblage, and there has never been any indication or claim of prehistoric human involvement with the remains,” said Logan Wiest and Don Esker, doctoral students in the department of geosciences, who have previously published on the Waco Mammoth site.

“We see similar bone damage morphologies at Cerutti as we do at Waco and in these other mammoth assemblages,” said Katie Binetti, Ph.D., senior lecturer in the department of anthropology. “And, crucially, all of this bone damage can be explained by processes other than that of prehistoric humans. In our opinion, this calls into question Holen et al.’s unique interpretation of the fracture history of the Cerutti mastodon’s bones.”

“We also dispute the geological argument that cobbles recovered from the Cerutti site could not have been introduced through natural, non-human processes,” said co-author Steven Forman, Ph.D., professor of geosciences. He indicated that the cobbles and pebbles were likely washed in from upslope of the site. “These processes occur commonly in Southern California and do not a priori reflect human agency.”

While the Baylor team states in the Nature article that they are theoretically open to the idea of human occupation of the Americas prior to 15,000 years ago, they contend that “Holen et al.’s extraordinary claim of prehistoric hominin involvement at the Cerutti site currently remains unsupported, with the presented evidence equivocal, and does not meet the high standards of proof to infer human agency. Until unambiguous evidence of hominin activities is presented, such as formal stone tools or an abundance of bone damage that has a clear connection to human activity (e.g., stone tool cut marks or hammerstone percussion pits), Holen et al.’s claims of prehistoric hominin activities in California 130,000-years-ago remain unproven.”

Authors are from Baylor University’s Institute of Archaeology and College of Arts & Sciences: Joseph V. Ferraro, Ph.D., associate professor of anthropology and director of the Institute of Archaeology; Katie M. Binetti, Ph.D., senior lecturer of anthropology; Logan A. Wiest, geosciences doctoral student; Donald Esker, geosciences doctoral student; Lori E. Baker, Ph.D., vice provost for strategic initiatives, collaboration and leadership development and associate professor of anthropology; and Steven L. Forman, Ph.D., professor of geosciences.


Baylor University is a private Christian University and a nationally ranked research institution. The University provides a vibrant campus community for more than 17,000 students by blending interdisciplinary research with an international reputation for educational excellence and a faculty commitment to teaching and scholarship. Chartered in 1845 by the Republic of Texas through the efforts of Baptist pioneers, Baylor is the oldest continually operating University in Texas. Located in Waco, Baylor welcomes students from all 50 states and more than 80 countries to study a broad range of degrees among its 12 nationally recognized academic divisions.


The College of Arts & Sciences is Baylor University’s oldest and largest academic division, consisting of 25 academic departments and seven academic centers and institutes. The more than 5,000 courses taught in the College span topics from art and theatre to religion, philosophy, sociology and the natural sciences. Faculty conduct research around the world, and research on the undergraduate and graduate level is prevalent throughout all disciplines.