Deep within the bowels of the University of Minnesota, a plastic tube filled with mud from an Indonesian lake bed inches its way through a machine.

By the time the sediment completes its pass through the "core logger," scientists will have a clear picture of what a faraway lake looked like centuries ago, as well as insight into what the lake might look like in the near future.

The university's civil engineering building basement houses the largest collection of core samples in the United States. Each year, hundreds of scientists send their mud, sediment and rock to the university's Limnological Research Center, seeking answers to vexing problems.

"A lot of the research we see focuses on climate change," said Anders Noren, director of the center's Continental Scientific Drilling Coordination Office (CSDCO). "Climate change is nothing new. The difference now is that the changes are much faster and more extreme. With core samples, we can see how temperatures changed in the past, so we have context for understanding how temperatures are changing right now."

Core samples contain fossil remains of pollen, algae and small organisms, as well as ash, storm debris and different types of rock. By analyzing them, scientists can reconstruct historical ecosystems to determine how climate has changed over time. They also can understand seismic and volcanic processes, and show how living things have adapted to their ever-changing environment. In fact, core samples can be used to answer big questions, like how humans left Africa. Was it out of a spirit of adventure, or to flee a changing climate?

That's what Prof. Alan Deino from the University of California, Berkeley is here to find out. Sitting at a 30-inch screen in the coordination office's unique laboratory, the National Lacustrine Core Facility (LacCore), Deino zooms in on cross-sections of core samples taken from the Rift Valley in East Africa. He is involved with the Hominin Sites and Paleolakes Drilling Project, an effort to understand climatic changes in Africa millions of years ago.

Closer to home, the laboratory is at the center of a heated debate over wild rice.

Core samples are helping the Minnesota Pollution Control Agency (MPCA) determine sulfate levels in Minnesota's waterways. Sulfate can be toxic to wild rice when it is converted to sulfide in the sediments, and is released into the state's lakes and rivers via wastewater or mining operations. LacCore data can help pinpoint exactly when sulfide levels became toxic. Using other data, it can paint a picture of what was going on in the ecosystem at that time.

This research is leading to new standards for sulfate levels in state waterways, but has also involved LacCore researchers in the debate on wild rice — sacred to the Ojibwe and other American Indians — the steel and mining industries, and protecting the natural state of the Boundary Waters Canoe Area Wilderness and other Minnesota environments.

Amy Myrbo, a LacCore/CSDCO research associate, is the lead investigator on the MPCA project studying wild rice. It's a natural extension of her previous role, working with the Fond du Lac Band of Lake Superior Chippewa researching the history of wild rice on the reservation.

Myrbo, 45, got the geology bug from a class she took at the University of Minnesota to fulfill a science requirement. She went on to get a doctorate. Myrbo spent the next 12 years working in the LacCore lab, loading mud-filled tubes into the core logger and analyzing the results. Now she splits her time between her own research on wild rice and trips to far-off locales to document core drilling projects affiliated with LacCore.

Projects like this and those in Africa or Indonesia help to explain why researchers like Myrbo spend so much time in the lab. A tube filled with mud can deliver critical information that helps societies live within, instead of in opposition to, the world around them.

"We do a lot with ground­water here in Minnesota," Myrbo said. "We help the Minnesota Geological Survey, for example, determine how population growth puts our water at risk. We can see how farming and clearing affects the environment, and determine what the natural state was before that. That helps a city manage the environment, maintain it, and have the chance to fix it up to its original state."

Sascha Matuszak is a Minneapolis-based freelance writer.