A Question of Balance

An introductory class in osteology–the study of the human skeleton–led Joan Brenner Coltrain to her life’s work: using stable-isotope chemistry to decode the secrets hidden in bones. Almost 15 years of pioneering research later, Brenner Coltrain is a research associate professor of anthropology at the University of Utah in Salt Lake City and a leading researcher in her field. She has a solid publication record, numerous National Science Foundation awards, and her own laboratory at the University of Utah.

Brenner Coltrain’s career has not followed the well-worn academic path. Instead, she has carved out a career by making choices consistent with her personal values and priorities. The result has been a richly rewarding journey that illustrates how family commitments can be balanced with academic achievement.

A delayed start

When Brenner Coltrain, a single mother, enrolled the youngest of her six children in kindergarten and signed up for an undergraduate degree in Hebrew and Middle Eastern studies at the University of Utah, she had no idea where her studies would take her.

A class in the rise and fall of civilization introduced her to the field of anthropology. The topic enchanted her so much that when she completed her undergraduate degree, she applied for a Ph.D. program in anthropology at the University of Utah. She was admitted to the program, but with no background in science and no previous degree in anthropology, she was rudderless. Even after several years of doctoral course work, she had no clear direction.

She was searching for a topic for an osteology class paper when anthropologist T. Douglas Price, currently at the University of Wisconsin, Madison, visited Utah to give a talk on his pioneering stable-isotope work in anthropology. Coltrain was intrigued by the method and decided to see whether she could use it to solve a long-standing puzzle in Utah prehistory: the role of maize in the diets of farmers living along the Wasatch Mountains east of Salt Lake City.

“When I came upon the topic, I realized it would do a couple of things for me,” Brenner Coltrain says. “First, I thought the diagnostic potential was important. Secondly, it would speak to my interest in biological anthropology–the hard science–rather than social or cultural applications. And third, there was no one in the department doing it.”

Despite her lack of hard-science training or an obvious mentor, she was hooked on the idea. She saw an opportunity to make a mark. There was a world-class isotope facility in Utah’s biology department. An encouraging reception from facility director James Ehleringer was all the invitation she needed to proceed with the project.

Unexpected results

The Wasatch Mountains form a natural divide running north to south through Utah. They mark the western edge of the Rocky Mountains and define the eastern margin of the Great Basin. The Fremont people, contemporaries of the better-known Anasazi, lived in the shadow of the Wasatch from 700 C.E. to 1300 C.E.

Anthropologists long argued that the Fremont subsisted mostly on wild plants and that corn was of little importance in their diets. But plants have different ratios of the stable isotopes of carbon 12 and 13, and these signatures are imprinted in the bones of animals–including people–that eat the plants. By studying the stable-isotope chemistry of ancient bones, Brenner Coltrain hoped to decipher the Fremont diet.

The results were stunning. “[The Fremont’s] reliance on maize was both much greater and more highly variable in some areas than had previously been thought,” says Jim O’Connell, a professor of anthropology and former chair of Brenner Coltrain’s department at the University of Utah.

“I produce 10 data points that completely undermine what everybody thinks they know about the archaeological record here,” Brenner Coltrain says. “It was really interesting, but other researchers were skeptical.” O’Connell says that researchers didn’t know what to make of her results. But the technique had the potential to peer much deeper into the diets of ancient peoples than anyone had ever looked before, and she was the first to apply the technique in the region. Her department encouraged her to continue.

Her next stroke of luck came in the form of a flood. Late-spring runoff from extremely high snowfall in the Wasatch Mountains inundated the Great Salt Lake. “It was an ecological disaster,” says Brenner Coltrain–but those snow clouds had a silver lining. When the wetlands flooded, vegetation washed away, revealing hundreds of previously unknown Fremont burials along the eastern banks of the lake. These remains afforded her a relatively large sample set, which became the basis of her doctoral research.

Because the field was emerging and no one in her department had the expertise to guide her, Brenner Coltrain had to organize her own curriculum, O’Connell says. She arranged an internship with geochemist Thomas Stafford at the University of Colorado, Boulder. (Stafford is now retired.) The 6 months spent in Stafford’s lab gave her the skills she needed to do the work she wanted to do.

Recasting obstacles as opportunities

Then there was the Fremont problem. Within the broader context of Southwest and Great Basin archaeology, Fremont archaeology is a pretty small field, O’Connell says, so Brenner Coltrain’s work garnered less attention outside Utah than might otherwise have been the case.

Strong family ties tethered her to Utah–plus, she valued the support of her colleagues and wasn’t eager to leave her department. Still, she knew that she had a marketable and fundable niche. Determined to roll constraints and opportunities–family responsibilities and research–together into a rewarding life and career, she published her Fremont results in top professional journals and, shortly after completing her dissertation, branched out of her Fremont niche. A University of Utah colleague–an anthropological geneticist–was investigating DNA from burials in the eastern Arctic. Brenner Coltrain suggested they collaborate to determine the relative importance of marine versus terrestrial food sources. But she could offer more: The techniques used to prepare samples for isotope analysis are also used for radiocarbon dating, so Brenner Coltrain could tell her colleague what his subjects ate and when they died. She also began to work on other Southwestern U.S. archaeology problems, including a detailed study of early Anasazi remains in Harvard University’s Peabody Museum of Archaeology and Ethnology.

She continues to venture outward, even as she stays at home in Utah. Currently, she is helping University of Florida researchers understand the diet of the Everglades’ Florida panther, which is nearly extinct. She has also partnered with Smithsonian Institution scientists to decipher the diets of colonial-era Jamestown residents.

Defining success

“A tenure-track agenda isn’t the only way to have a meaningful career and make a meaningful contribution,” Brenner Coltrain says.

“There are clear tradeoffs in this discipline,” she says. “I love what I do, but I negotiate a contract year to year. It’s my choice. My children are here. My husband’s business is here”–she has remarried. “And the department has been wonderful.”

“No one can doubt that if offered tenure, I would take it,” Brenner Coltrain says–but tenure isn’t the only measure of success. “I see women frantically attempting to raise a family and negotiate an academic career and compete with individuals who don’t have a dual role to fill. I love my research, but it had to be negotiated relative to my family responsibilities.”

DOI: 10.1126/science.caredit.a0700041

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