Exploring the Haffenreffer’s Lithic Collection
Today’s post is from Colin Porter, who will defend his dissertation in Anthropology at Brown University this spring. He reports on research conducted as a proctor at the museum in fall 2012.
Archaeologists endeavor to understand changes in human behavior over time through the systematic analysis of its physical residues: hand axes, ceramic shards, cigarette butts, and whatever else people have left behind. However, environmental conditions—soil acidity, free-thaw cycles, sea level change, and so on—conspire to leave archaeologists with only faint traces of past cultural activity.
Despite more than 12,000 years of human occupation in New England, the region is notorious for poor artifact preservation. Here, archaeologists often identify archaeological sites dating to before the era of European colonization (ca. 1500 AD) by a scatter of stone tools. The Haffenreffer Museum of Anthropology currently curates more than 50,000 stone tools, many collected from sites near the Collections and Research Center in Bristol, Rhode Island.
Archaeologists have long observed that the size and shape of lithic, or stone, tools vary predictably across space and time and offers rich data for cultural analysis. In particular, triangular dart and arrow points—those lacking stems and notches—are commonly found on archaeological sites across northeastern North America. Since the 1960s, archaeologists have classified these artifacts as one of four types based on their size and shape: Squibnocket (small and heart-shaped), Beekman (small and equilateral), Madison (small and isosceles), or Levanna (large and equilateral).
However, triangular points are often difficult to classify in practice. Specimens excavated from archaeological sites were often broken when they were deposited in the soil. Others intergrade—they bear characteristics of two or more types—which makes classification difficult, if not impossible. In recent years, some archaeologists have decided to give up the existing typological framework altogether.
As a museum proctor during the fall semester, from September to December 2012, I conducted an independent study of 623 triangular points from HMA’s lithic collection. I classified, measured, and recorded formal characteristics of each point (curvature of base and sides, material, and presence/absence of a tang). Then I performed a hierarchical cluster analysis, a type of quantitative analysis, to group the artifacts based on shared similarity. Finally, I performed a spatial analysis to examine the geographical distribution of different clusters.
The study revealed an alternative taxonomy of triangular points based on tool morphology. When these clusters were mapped, some clusters showed different geographical distributions. In particular, the presence of a basal tang, which appears on both Madison, Squibnocket, and Levanna types, is confined to a relatively small geographical area around the northern coast of Narragansett Bay. This evidence of intra-regional variation in material culture suggests differences in other, more ephemeral cultural practices.
Exploratory analysis of existing collections can not only generate new hypotheses for future evaluation, but also lead to better classification of specimens in the museum. While archaeologists know relatively little about the expanse of human history in New England, we are constantly learning more. The HMA’s lithic collection, one of the largest in the region, has been essential to this mission, and will continue to be so into the foreseeable future.
Thanks, Colin! Readers, you can learn more about Colin’s research on colonialism, material culture, and social memory in northeastern North America at http://www.brown.edu/Departments/Anthropology/people/cporter.html
And please note: we welcome guest bloggers! If you are interested in writing about your experience with the Haffenreffer, please contact Jennifer_Stampe@brown.edu