This month, Arctic ground squirrels emerge in Alaska after eight months' hibernation.
WHEN an Arctic ground squirrel hibernates, its body temperature drops below the freezing point of water and the blood-flow through its brain slows to a trickle.
Any incipient hibernation, shown for instance by the arctic ground squirrel, proves abortive, as the animals will shiver themselves awake after only a few days.
The fruit was stored by an arctic ground squirrel in its burrow on the tundra of northeastern Siberia and lay permanently frozen until excavated by scientists a few years ago.
Hibernation period of the Arctic ground squirrel.
Q: What got you interested in studying arctic ground squirrels?
Arctic ground squirrels could play a greater role in climate change than was previously thought.
The Arctic ground squirrel normally maintains a body temperature similar to our own.
Before entering hibernation Arctic ground squirrels almost double their body weight.
Mr Golden said: "We saw an increase in soil temperature in the soils where the arctic ground squirrels were occupying.
For instance, we have a new project that will see how hormones are involved in arctic ground squirrel hibernation.
