Nature's frozen vertebrates: surviving as a solid
The scarcity of food and freezing temperatures during winter drive many Canadian animals into hibernation - even though many of these organisms find themselves a hair's breadth from death.
The scarcity of food and freezing temperatures during winter drive many Canadian animals into hibernation - even though many of these organisms find themselves a hair's breadth from death. Torpor, the scientific term for deep hibernation, involves a drastic suppression of metabolic rate. In warm-blooded animals torpor is certainly not a pleasant slumber. Metabolic rate in ground squirrels can fall by 96 percent, as their body temperatures reach ambient levels. In chipmunks, heart rate plummets from 400 drum beats per minute to a crawl of 23 beats per minute. In cold-blooded species, such as turtles and frogs, hibernation is quite literally blood-chilling. As much as 65 percent of the animals' body water can become solid ice. Despite the absence of a heartbeat, these organisms still revive at the onset of spring. Ken Storey, the Canada Research Chair in Molecular Physiology and professor of biochemistry at Carleton University, uses molecular tools to identify the genes that allow these death-defying animals to survive the winter freeze. His research may one day herald an exciting new technique to prolong the shelf life of human transplant organs so surgeons no longer face a race against time when transferring life-saving body parts.
Dr. Storey will present the Marsden Public Lecture in McGill University's historic Redpath Museum Auditorium at 3:30 pm on February 19. Information: 514-398-6401.