“There’s me,” said ASIF Director Matthew Wooller, pointing to a blue magnet that’s just offset from the rest. Wooller is a vegetarian, resulting in a slightly different isotope signature than more omnivorous humans.
“You’ve heard the phrase ‘You are what you eat?’” Wooller asks. “That’s what this is.”
That phrase isn’t always meant literally, but in this case it comes close. ASIF, located in the Duckering Building at the University of Alaska Fairbanks, is built to analyze some of the common elements, such as carbon, nitrogen and oxygen, that exist in every living thing. By studying samples of hair, flesh, bones and blood, Wooller and his team can create an outline of their life story — what they’ve eaten, where they’ve lived, and sometimes even when they existed.
“Isotopes don’t lie”
If someone drinks water from Alaska, the chemical composition of their body is different than their cousin who drinks water in Ohio. A person who regularly enjoys a slice of carrot cake for lunch will have a different isotopic signature than someone who snacks on raw carrots. Depending on where they’ve lived and what they’ve consumed, the same chemical clues exist in a polar bear, a dandelion or a mosquito.
When it comes to isotope science, the “Board of Truth” is just that.
“Isotopes don’t lie,” Wooller said. “That’s not saying that people always do, but they’re sometimes not great at recording or remembering what they eat and what they do. Isotopes are good at that.”
That inherent honesty has given ASIF a role in a remarkable variety of research projects. Although it’s one of many isotope labs, both in the U.S. and internationally, ASIF’s location has given it an instrumental role in Arctic research.
In recent years Wooller has participated in major studies about extinct woolly mammoths, the range of prehistoric Bering Sea ice and the lives of Alaska’s earliest human inhabitants, just to name a few.
“It’s remarkable,” said Patrick Druckenmiller, the director of the University of Alaska Museum of the North. “It allows you to study animals and do things in ways that we were never able to do before.”
Pursuing ‘a big detective story’
The varied equipment that fills the labs at ASIF — test tubes, lasers, spectrometers and computers — works together for a common purpose. Elements like carbon and nitrogen come in “light” and “heavy” forms, and isotope labs work to determine how much of each is in the specimens it tests.
Photo caption: A vast collection of mammoth fossils, including a jawbone with teeth, are stored in the Collection Range at the UA Museum of the North.
A bowl marked “walrus teeth” sits on a small table, and sure enough, it’s full of massive, jagged molars. Bird skeletons, trays of insects, caribou skulls — just about any random piece of an Alaska species seems to be around somewhere. Wooller and Druckenmiller were there for the mammoths, shuffling through more than 100 gigantic tusks stashed above the high shelves in the middle of the room.
Wooller gestured to one split lengthwise, exposing a layered cross-section. “I don’t think there are many museum directors who would let you do something like that,” he said.
That may be true. But Druckenmiller is among a number of scientists who, even though they don’t have a background in isotope science, have developed an appreciation for the discipline.