Dark winters make everyone want to sleep a little longer, but some animals spend the whole winter fast asleep, a strategy West Ridge researchers are studying.
"Given that we live in the arctic, one of the research themes, particularly in the Institute of Arctic Biology, is how animals can survive in such extreme conditions," said Brian Barnes, director of the Institute of Arctic Biology.
Barnes and fellow UA researchers, including professor Kelly Drew and graduate students Tulasi Ram Jinka, Robert Fridinger and Trixie Lee, have focused on two species ability to hibernate through the winter -- the arctic ground squirrel and the black bear -- in their quest to understand arctic animals' survival.
"The basic reasons for the studies are understanding the limits of design and adaptation to northern habitats and applied results in fields such as medicine," Barnes said.
Researchers at UAF have been studying squirrels' hibernation at UAF for more than 20 years. The bears are a more recent test subject, only arriving on campus in the last five years.
"We haven't had the genetic and molecular tools to study black bears until more recently," Barnes said.
Genomics and proteomics, two fields of study that have developed to study genes and proteins, have helped make studying bears more feasible, he said.
According to Barnes, the questions being asked about bears are similar to those of squirrels. Bears hibernate at a warmer temperature, which raises more questions about how body temperature is related to hibernation, he said.
"It's a different way of solving the problem," he added.
According to Barnes, "Animals that can't find food, what do they do? They go into hibernation. Hibernation, from its Latin roots, is to spend winter in a lethargic state."
During hibernation, animals essentially go into suspended animation, Barnes said. Over the summer, squirrels bulk up in preparation for their six-to-eight month deep sleep, he said. In the summer, arctic squirrels have a normal temperature of about the same as in humans. But during hibernation their body temperature can safely dip below freezing, Barnes said. Arctic squirrels have reached the lowest temperature of any mammal on earth. The lowest recorded temperature has been below 3 degrees Celsius, he said, at which time the squirrel was considered to be in the super cold state.
"The squirrels cleanse their blood of ice nucleators, and enter super cold for up to three weeks," Barnes said.
By cleansing their blood of ice nucleators, a particle in the blood, the squirrels prevent their blood from crystallizing, causing them to freeze, Barnes said.
Every three weeks, the squirrels warm up again using their brown fat to create heat and warm them to a normal temperature for one day, he continued. "How the brain regulates this, the heart and liver response, we want to know how ground squirrels can change the regulation of their body in such a profound way, and what the limits to design and function are in mammals," Barnes said.
Ground squirrels are also more resistant to trauma than other animals, because they are able to lessen the brain's demand for oxygen and other nutrients. Studying how other mammals withstand lower temperatures is expected to provide insight that can be used by medical professionals.
"They're problems of supply and demand," said Barnes. "When you have heart attacks and strokes, your ability to supply oxygen to the body is a problem, we're looking at how to drop the demand."
Funding for the hibernation research comes from a variety of sources, including the U.S. Army medical Research and Materiel Command, American Heart Association, National Institute of Health, and National Science Foundation, said Barnes. For the most part, those groups are most interested in the medical applications of the research, he added.
