The adult and larval versions of the red flat bark
beetle, one of the hardiest organisms in Alaska.
Photo by Ned Rozell
This column is provided as a public service by the Geophysical Institute, University of Alaska Fairbanks, in cooperation with the UAF research community. Ned Rozell is a science writer at the institute.
As we pull on winter coats and wool hats to shield our tropical bodies from the cold, there is a creature in our midst that survives Alaska’s coldest temperatures bare-naked.
The red flat bark beetle lives as far north as there are balsam poplar trees in Alaska, hunkering down for the winter in the moist area between dead bark and tree. Scientists like Todd Sformo, from the University of Alaska’s Institute of Arctic Biology, find most of them in the larval stage, where they resemble segmented worms a bit longer than a grain of rice. He finds a smaller number of adults that have handsome segmented bodies the color of teak.
The beetles are special among living things in Alaska because they have the ability to spend the winter above the snow, exposed to the coldest air of winter. Sformo, a graduate student working in Professor Brian Barnes’ lab, has cooled the beetles to minus 94 degrees Fahrenheit (minus 70 degrees Celsius) in the lab, and they have not died. Yellowjackets, stinkbugs, and other insects that survive winter using the same strategy, known as supercooling, perish at about minus 13 degrees Fahrenheit (minus 25 degrees Celsius).
“They really have to be under that leaf litter and under the snow (for insulation from the cold air),” Sformo said.
How cold can the bark beetles get?