During the summer of 1964 when the U.S. Congress debated and passed the Wilderness Act, a very different act took place in the mountains of Nevada: a 5,000-year-old tree that turned out to be the oldest living individual organism on earth was cut down in the name of science. The destruction of the bristlecone pine that became known as Methuselah continues to reverberate in scientific and environmental circles. Essays, poems, and songs have been composed in commemoration, field research protocols have been reformed, Great Basin National Park was founded to protect other ancient bristlecones, and the tale of this strange destruction remains a favorite cautionary tale told to biology students.
Why? Why does such venerability matter? What can this “charismatic species” tell us about ecological integrity, human survival, and human-driven climate change?
Such questions are on the mind of James Capshew, the Center’s Gordon/Horning Visiting Fellow and a professor of history and the philosophy of science at Indiana University. Investigating the mystique of the bristlecone pine is part of Capshew’s larger project on the history and sociology of dendrochronology, the study of tree rings. “This small scientific field is concerned with establishing long chronologies through tree-ring research,” said Capshew, noting that as far back as Leonardo da Vinci’s day some attention was paid to the meanings of tree rings. It was not until the early 20th century, however, that a scientific methodology developed. “Dendrochronology has many applications in archaeology, climatology, ecology, and other areas, including art history, where it has been used to determine the provenance of wooden substrates of early modern paintings and musical instruments. . . Although the field has been in existence for nearly a century and has all the trappings of a maturing science, relatively little historical research has been done on the discipline of its practitioners.”
The systematic study of tree rings developed, surprisingly, from the work of an astronomer whose principle interest was the influence of sunspots on the earth’s climate. A.E. Douglass, of the University of Arizona, developed the method for cross-dating tree ring specimens, and by 1919 he had measured 75,000 rings from the U.S. and Europe. In 1937, he established the Laboratory of Tree-Ring Research at the university. Douglass’s students have played a prominent role in the field ever since; one of them, geographer Donald Currey, was the now infamous man who caused the death of Methuselah. Though accounts vary regarding what actually happened, a common version is that the boring tool he used to get samples—a benign method for the trees—broke in the field and he asked the local ranger for permission to cut down a tree to complete his research.
The tree turned out to be at least 4,900 years old. In subsequent accounts, Currey stated that he wanted a record from as old a tree as possible but had no idea his choice was the oldest in the world or even in that region. The uproar that swelled following the death and dating of the tree led, among other things, to the founding of Great Basin National Park in 1986. It also raised many scientific, philosophical, and cultural questions. As one essayist wrote, “As it turns out, the longevity of these trees revealed only the beginning of their value. Their value came not only from their age, but from how they aged, what their aging revealed, how their aging was related to the environment in which they lived.” Another noted that “their value comes from what humans imagine these trees to have witnessed. . .”
Capshew’s interests include the principles, methodologies, and aims of dendrochronology coupled with sociological research into the demography and ethnography of the tree-ring scientists. “The primary method of cross-dating tree samples and its possible relation to use of the ‘personal equation’ in nineteenth-century astronomy raises intriguing questions about how to standardize the human observer in order to create reliable data.” The term “personal equation” in 19th- and early 20th-century science referred to the idea that every individual observer had an inherent bias in regard to observation and measurement. It originated in astronomy on the discovery that investigators making simultaneous observations were likely to record slightly different values, leading many scientists to be skeptical of the findings of others. “Dendrochronologists inhabit a scientific space where the interpretation of tree rings is a paramount goal. . . To understand their beliefs, values, and behavior toward their objects of study—trees—could shed new light on the science and culture matrix.”
James Capshew is the author of: Psychologists on the March: Science, Practice, and Professional Identity in America, 1929-1969 and Herman B. Wells: The Promise of the American University.