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Ice worms on the glacier
Scientist probes the mysteries of tiny critters in very cold water
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Despite so much time with worms, Shain admitted that their behavior remains pretty hard to fathom. For instance, no one can explain the central question of ice worm existence: How are they able to exist only at 0 degrees Celsius?
Warm weather liquidates them. (They turn to mush.) And they will quickly die if they get too cold, a problem for surviving Alaska's winter.
''There are some big questions about what ice worms do in the winter,'' Shain said. ''They're very sensitive to cold. So they're going to have to burrow down somehow.''
Unlike other animals adapted to arctic conditions, ice worms are perpetually chilled to the freezing point of water at a cellular level -- a condition that would annihilate their genetic cousins, small worms in the Enchytraeidae family.
''There's probably no other animal in the world that could develop from egg to an adult at 0 degrees Celsius,'' Shain said. ''It's a huge obstacle that they've overcome. ... You appreciate it so much more when you're on the glacier freezing your ass off.''
But there are many more mysteries. How do ice worms find each other? How do they know when to submerge or surface? Shain has clocked big, lone worms traveling away from colonies at a lightning-paced slither of about 10 feet per hour. Are they establishing new colonies? Or just lost?
''I call them 'trekkies,' '' Shain said. ''They seem to be pioneers, to strike out where no ice worm has gone before.''
Still, judging from experiments at the lab and observations this summer, Shain said he suspects that the worms may be responding to multiple clues: sunlight, temperature, gravity, chemical trails on the ice, and an internal circadian rhythm.
Which adds up to a pretty amazing repertoire for a creature no thicker than a piece of string.
''They are definitely the most sophisticated animal that lives under these extreme conditions,'' Shain said. ''But the bottom line is we don't know how they navigate.''
Up on the Learnard Glacier two weeks ago, Shain and his two students wandered around, bent over, studying the ice. In one place, they found the worms had mixed in with silty muck. Some of the worms appeared reddish in the mud, then darker on the snow. What did that mean?
As the evening approached, more worms surfaced. They oozed this way and that -- up walls, down cracks, across scalloped basins. Hundreds of them festooned the walls of icy pools, oblivious to the current of rushing meltwater.
''This is a complete ice worm Jacuzzi,'' declared Shain, as he happily shot video and scooped samples. ''This is why I came. This is what I wanted to see.''
Despite the mysteries surrounding their lives, these worms seemed driven to rise, to surface, to spread across the ice. Perhaps one thing was certain.
''They're going out for dinner,'' Shain said.
(Reporter Doug O'Harra can be reached at do'harra@adn.com.)
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