By Steven Krolak
(NEW ALBANY, Ind.)—A life-size bronze statue of a woolly mammoth stands in front of the Nebraska State Museum in Lincoln, Nebraska.
Inside the Museum, in a room colloquially known as Elephant Hall, mammoth and mastodon skeletons tower over visitors, giving a sense of the size and strength of the large mammals that once roamed the Great Plains.
For David Treves, it was a magical place to grow up.
His father was a geologist at the University of Nebraska, and Treves and his brother spent many happy hours amid the massive and haunting displays, free to follow their curiosity wherever it might lead.
Treves also accompanied his father and other researchers, including students, on geology field trips, learning to look at the land with a scientific eye, to unlock the systems that underpin life on Earth.
Fast forward to today: Treves is a professor of biology at IU Southeast. Now it’s his turn to guide students on research trips, sometimes to the campus pond, sometimes as far as Big Bone Lick State Park in northern Kentucky, a place that has a curious personal resonance.
But we’re getting ahead of ourselves.
Suffice it to say that Treves now seeks to unleash in his students the same mixture of curiosity and awe that he first felt in Elephant Hall, using the advanced laboratory tools to design projects that put students on a path to discovery.
A love story
Treves did not follow in his father’s footsteps. He veered into biology as a student, intending to become a doctor or veterinarian. But a summer research project in microbiology and ecology changed his trajectory.
“That’s when I fell in love,” Treves said. “I had a project, I had a place in the lab, I was given objectives, I was collecting data.”
He had the patient temperament for the lab and the exploratory zeal for field work. By the time he reached graduate school, he had figured out a way to blend the two: microbial ecology.
As an instructor, Treves serves up this blend to his students, combining sampling in the field with rigorous but enjoyable exercises in the lab.
In seeking to kindle the same enthusiasm in students that marked his own learning journey, Treves is aided by advances in the field, driven by technology.
“There have been revolutions in microbiology that allow us to see more of what’s in soil and water,” Treves said. “Beyond that, these advances have also made DNA sequencing more cost-effective.”
The combination of technical and economic breakthroughs has made teaching and learning microbiology a whole new game.
A career in a puddle
Treves uses an approach he calls discovery-based learning.
It all starts in the sulphur springs at Big Bone Lick State Park. Here samples have been collected from a rather unusual environment: a low temperature sulphur spring. While hot springs and the life inside them have been extensively documented, the microbial ecology of cooler springs like those at Big Bone Lick have been very poorly characterized, and this presents a unique research opportunity, according to Treves.
“The bugs we are studying could be new species,” Treves said. “You could spend a career on a puddle like that.”
Back in the lab, students isolate the bacteria, and are then given one or two isolates to characterize. Most of them are working on species unknown to science. Throughout the semester, students will have become experienced in the handling of bacteria, so there is a structure, but they are still freedom to expand, try out new methods, and put an individual stamp on the work. Over the course of six to seven weeks, the students use molecular biology to identify the bacteria, they touch bioinformatics when they send samples off for DNA sequencing, and they apply traditional techniques when it comes time to characterize the sample.
Science moves slowly, and sometimes it doesn’t move at all.
“In many research projects, there are spans of six months or even a year when not much happens,” Treves said.
But meeting twice per week, his class moves swiftly.
“We can do in half a semester what many schools will take an entire semester to accomplish,” Treves said.
This gives students an experience that stretches from a prehistoric pond to a poster presentation of the results of their analysis.
Along the way, students come to understand that the outcome may not be what they expected or hoped for, but that there is no real failure, because something was learned. They have collected data and received a DNA sequence for their bacteria, they will have described its interesting characteristics and plotted its taxonomy.
Most importantly, there are more questions.
Treves does not expect that many students in his class will become microbiologists. His course is not a requirement for the biology program at IU Southeast, but still attracts a diverse group of students, from biology and chemistry majors to pre-med and pre-vet aspirants.
From his perspective, exercises like the halophile project have a value that transcends the narrower confines of the career.
“Immersion in the project, how to design it, how to collaborate with others, how to think critically and present information—these are all great life skills,” Treves said. “I hope that students leave with a broader appreciation for the field of microbiology, and of all the connections there are to other disciplines.”
Many of those connections are explored in another innovative project called the journal club, in which the students dissect a scientific journal article, working backwards from the results to analyze the methodology, and to discuss how different approaches might have been more effective, or yielded different outcomes.
Treves often begins the entire semester by asking students if they have an interest in a certain microbe or bacterium, and often receives responses about diseases in the news—Salmonella, ebola, measles. By the end of the term, the consideration of these issues has moved from a public health context to a discussion about experimental design.
Passing the torch
When he first arrived at IU Southeast, Treves asked Dr. Claude Baker, the campus ecologist, about likely places for field work. Baker recommended Big Bone Lick, where he had been taking students to sample flora.
The area is now mainly known for its sulphur and salt springs, but for over two centuries it was revered as the birthplace of modern vertebrate paleontology—hence its name.
Beginning in the 1700s, a long line of professional scientists and enthusiasts from around the world—including the Scottish geologist Sir Charles Lyell—made their way to this area, lured by its wealth of mammal bones from the Ice Age. Besides mastodons and mammoths, Big Bone Lick has also yielded the bones of bison, musk oxen, giant ground sloths, tapirs, as well as wild horses, wolves and bears.
Once at the park, Treves noticed a plaque commemorating the area’s role in paleontology. He began connecting some interesting dots.
As a boy, Treves had met Dr. C.B. Schultz in the Elephant Room. Schultz was a leading paleontologist at the University of Nebraska who had collected a great many of the mammoth bones that filled Treves with such wonder.
It turns out that Schultz had led a major expedition in 1962—to Big Bone Lick.
Today Treves smiles at the thought that the very bones he admired as a boy—specimens that nourished his growing love for biology—were most likely taken from the same spot that now serves as a classroom for students of his own.