Studying Belgica at the Bottom of the World

(Thanks to Yuta Kawarasaki for help with this post.)

Belgica larvae can survive freezing

Whenever I tell someone about Belgica, I always mention it can survive freezing. But what’s so amazing about that?

Belgica, other invertebrates, reptiles, fish, and amphibians are ectotherms (“cold blooded”). The body temperature of ectotherms depends on the temperature of their surrounding environment. In other words, if the air or other material surrounding an ectotherm is cold enough, the body fluids of that animal can turn to ice.

But very few animals can survive having ice in their bodies. Ice can deform or break cells and can prevent body fluids from carrying oxygen and nutrients. Ice can shut down important organs, like brains and hearts. So how do our little Antarctic flies do it?

Their trick is to make lots of cryoprotectants. Cryoprotectants are sugars and/or alcohols that protect cells from being damaged by freezing. As water in an animal’s body goes from a liquid to a solid, that animal’s cells shrink and the delicate machinery in the cell can stop working. Cryoprotectants can act as a substitute for water, helping cells keep their shape. Cryoprotectants also help limit the amount of ice that can form.

Here’s another neat fact about Belgica: it doesn’t always freeze during cold spells. This fly can also survive freezing conditions by cryoprotectively dehydrating, or losing so much body water that ice can’t form in the first place!

Here are a few other animals that can survive freezing:

• Wood frogs
• Painted turtles
• European common lizards
• Arctic wooly bear caterpillars
• Siberian timberman beetles

After reading this, you might be tempted to try freezing animals at home. But beware! Most household freezers are too cold, even for animals that can handle having ice in their body. Also, many animals that can freeze can only do it in the fall or winter. If you want to safely freeze an animal at home or at school, check out the goldenrod gall fly activity on our website.

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This week in Antarctic science history

On December 14, 1911, the Second German South Polar Expedition entered the Weddell Sea.  The leader of the expedition, Lieutenant Wilhelm Filchner, thought that East and West Antarctica were two separate land masses covered by ice.  (They’re not—the two parts of the continent are separated by a mountain range, not water.)  Unfortunately, Filchner didn’t get to test his hypothesis because his ship, the Deutschland, got stuck in sea ice until November 26, 1912. 

The first flight of the Cosmic Ray Energetics and Mass (CREAM) mission started on December 16, 2004.  The equipment used on the CREAM mission was carried by a special balloon launched near McMurdo Station, Antarctica.  You can see a video of the balloon being launched here.  Cosmic rays are sub-atomic particles from outer space that strike the Earth at high speed.  These tiny particles give scientists clues about what the galaxy is made of and how it works.

On December 18, 1911, Charles Wright collected a handful of pebbles near the Beardmore Glacier that later revealed the first fossilized sponge from Antarctica. Wright would have appreciated the CREAM experiment described above. Although he was officially a glaciologist for the British Antarctic Expedition, his true scientific passion was cosmic rays (or “penetrating radiation”, as they were known at the time).