Contributed by Ryan Wheeler
Richard “Scotty” MacNeish (1918 – 2001) was a preeminent archaeologist of the mid to late twentieth century. Along with roles at the National Museum of Canada, the University of Calgary, and Boston University, Scotty was the fifth director of the Robert S. Peabody Foundation for Archaeology (now the Robert S. Peabody Institute of Archaeology). First associated with the Peabody in the early 1960s, he worked closely with Frederick Johnson and Douglas Byers, who assisted him with the Tehuacán Archaeological-Botanical Project, probing caves in central Mexico for the world’s earliest corn. Throughout his career, MacNeish sought the intertwined origins of agriculture and civilization, working in various parts of Mexico, Peru, China, Belize, and North America.
Along with impressive ceramic chronologies and pretty old—if not the oldest—examples of corn, Scotty often also reported evidence of great human antiquity in the Americas. At a site highland Peru MacNeish claimed that the earliest levels had evidence of crude stone tools and Pleistocene megafauna dating to well over 14,000 years ago.
At Pendejo Cave on the Fort Bliss military base in New Mexico he claimed even earlier dates, including occupation levels between 25,000 and 31, 000 years ago. This was at a time when Clovis—named for the type site of distinctive fluted spear points dating to around 12,000 to 13,000 years ago—was considered the earliest human occupation of the Americas. Scotty was a strong proponent of the pre-Clovis hypothesis, which now dominates in archaeology.
But Scotty MacNeish wasn’t the only twentieth century archaeologist with claims for early sites. In the 1960s California archaeologist Ruth DeEtte Simpson recruited Louis Leakey to aid in investigation of a site on Bureau of Land Management property in the central Mojave Desert. This was the Calico Hill Early Man site, which produced crude chipped stone tools, some possibly dating between 100,000 and 200,000 years ago! As you might imagine, these early dates caused quite a stir and led many archaeologists to reject the Calico Hill site. Some argued about issues with dating, while others posited that the stone tools were really just natural phenomenon. Prior to his death in 1972, the Calico site may have caused a rift between Louis and Mary Leakey. And despite criticism, Simpson continued excavations.
A conference on the site failed to garner critical support from other archaeologists—many lauded the careful techniques employed, but balked at the early dates (see report by Walter Shuiling 2015). In his 1978 review of early sites in the Journal of Anthropological Research, MacNeish writes, “The most disputed of these is Calico Hills of California with geological estimates ranging from 50,000 to 200,000 years ago.” He goes on to say that, despite doubts about the site and its contents, he believes the tools are “pebble and slab choppers, spokeshave-like tools, large side scraper and plano-convex scraping planes or cores” like those at other early, pre-Clovis sites.
It is probably not surprising, given his support for the site, that Ruth Simpson invited MacNeish to participate in a thirtieth anniversary celebration of the Calico Hill Early Man site. The event, sponsored by the Friends of Calico, the San Bernardino County Museum, and the Bureau of Land Management, was held over two weekends in 1994. MacNeish delivered his talk, Pleistocene Man & Animals in the Pendejo Caves on Saturday, November 5, 1994. MacNeish acquired a set of nice resin casts of the artifacts from Calico Hill at this time, which he gifted to the Peabody. These include the Rock Wren biface—another large chopper-like tool—that has been dated to a more recent era with thermoluminescence dating.
The Calico Hill Early Man site, however, does have a little company in the contention for earliest possible human habitation in the Americas. A recent paper in Nature reports on the remains of a 130,000 year old mastodon site with some evidence of intentional bone breakage. Interestingly, the Cerutti Mastodon Site is in San Diego, about 186 miles from Calico Hill in the Mojave Desert. Like Calico Hill, most archaeologists have dismissed the San Diego site. Despite the skepticism around the claims for very early sites, archaeologists have continued to push back the earliest dates for humans in the Americas, with some sites dating to between 14,000 and 19,000 years ago.