illustration by Sasha Prood

Bones, Stones, and Genes

The 2011 Holiday Lectures series delves into where we came from and how we got here.

Teaching human evolution is not always straightforward, even when you have an advanced degree in the subject. Take biology teacher Keri Shingleton. She has a Ph.D. in evolutionary biology and teaches biology courses that cover human evolution at Holland Hall, a private Episcopal-affiliated grade school in Tulsa, Oklahoma. Yet even she has shied away from the topic, admitting, “Perhaps I had a bit of a misconception that there were still too many unknowns.”

Although Tulsa is a very conservative city, the administrators at Holland Hall stand by Shingleton’s decision to teach human evolution. “But that doesn’t mean I don’t have students in my classroom who are opposed to what we teach,” says Shingleton.

Shingleton is one of 14 teachers from around the U.S. who were invited to attend the 2011 HHMI Holiday Lectures on Science this past October. The teachers joined about 200 Washington, D.C., area students to learn answers to questions about human evolution such as: Where and when did humans arise? What distinguishes us from other species? Did our distant ancestors look and behave like us? More than10,000 other students and teachers watched a live webcast of the lectures, titled “Bones, Stones, and Genes: The Origin of Modern Humans.”

“We chose to focus on the origin of modern humans this year because understanding where we come from and how we got here is one of the most fundamental questions that humans have asked for ages,” says Sean B. Carroll, vice president for science education at HHMI. “Due to local controversies about the teaching of evolution, many kids don’t get exposure to good information on the topic. We want to equip teachers with the best information available from leading figures in this quest.”

Recent advances in paleontology, archeology, and genetics prompted HHMI to invite three dynamic speakers from very different research fields to participate in this annual series that aims to bring the latest scientific developments into the classroom.

Tim D. White, a paleontologist at the University of California, Berkeley, took the audience through time, describing fossil evidence for human evolution from Africa to Europe and explaining how the great apes fit in the tree of life.

The students and teachers learned about stone tools—the most durable evidence for human evolution—from John Shea of Stony Brook University. Shea, an archeologist and anthropologist, explained that these tools can give us clues to what life was like for humans who existed thousands, and even millions, of years ago. After the lecture, the audience joined five experts in what may have been the largest stone tool-making session in the history of human evolution. Donning safety goggles, lab coats, gloves, and protective booties, the students and teachers set to work on about 550 pounds of dacite rock with 80 hammerstones.

Although two emergency medical technicians were on hand to deal with injuries caused by flying rocks and wayward hammerstones, only a few Band-aids were needed. “I thought it was going to be difficult and that I would be hitting my fingers, but once I figured out the flip of the wrist, it worked pretty well,” says Leslie Mark, a student at Dominion High School in Sterling, Virginia. “After I got the hang of it and I was actually getting a shape out of my stone, it was pretty cool.”

“These are the skills that got our ancestors through the last ice age,” explains Shea. “To get our species through the next one, it is important that these skills be passed along to our descendants. I think of teaching flintknapping as a kind of ‘extinction insurance’ for Homo sapiens.”

Making Flakes

Take in the sights and sounds as 200 Washington, D.C.-area students try their hands at making stone tools.
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Moving from the field to the lab, genetic anthropologist Sarah Tishkoff, of the University of Pennsylvania, explained how scientists are using genetic methods to analyze DNA variation among early humans and learn about their relationships to modern humans. Tishkoff studies the genetic variation in modern humans and nonhuman primates, such as chimpanzees, to learn more about the evolutionary forces that shape and maintain genetic variation in modern populations. Students got to explore their own genetic variation by analyzing their saliva for different versions of a gene that controls perception of one type of bitter taste.

After the lectures, the 14 teachers had one-on-one time with the scientists, then stuck around for a few days exchanging ideas on how to craft educational resources based on the lecture series and implement what they learned in the classroom. Many participants really appreciated this aspect of the lectures. “As a teacher you don’t get a whole lot of time to talk to other educators and exchange ideas; you are kind of isolated in your classroom,” says Randi Neff, a science teacher at Tuscola High School in Waynesville, North Carolina. “Being able to exchange ideas with other people who are in the same business as you is a rare occasion.”

Shingleton left HHMI energized and ready to teach her students about human evolution. “There’s a lot more information than I realized,” she says. “I’ve never synthesized the ideas of archeology and paleontology. When you put all of that together it paints a bigger, more complete picture that I feel much more confident presenting in my classroom.”

Scientist Profile

Vice President, Science Education
University of Maryland
Genetics, Molecular Biology