Antarctic Isopods

How many of you know what an isopod is?

If you do, that's FANTASTIC!

If you don't, well don't feel bad because if you keep reading you will.

Isopods are crustaceans. Crustaceans are organisms that have an exoskeleton, segmented bodies, and jointed limbs. This group includes not only isopods but also crabs, lobsters, shrimp, and many more.

Pictured: A crustacean.

Isopods are specifically crustaceans that have flat bodies and seven pairs of limbs. Some species of isopods live on land, while others live in the water. You may be familiar with a common terrestrial (lives on land) isopod, known as the pill bug.

Trust us, there are seven pairs of limbs there.

We currently have in our lab some exoskeletons of some Giant Antarctic isopods. Giant Antarctic Isopods live in aquatic environments and, as can be expected from the name, are quite large.

 For more isopod photos CLICK HERE!

These guys were caught by a trawler off the Antarctic Peninsula.

This bit.

The handy thing about only having the exoskeletons, is that exoskeletons are made out of chitin, a material that doesn't rot, so we don't need to keep them refrigerated or anything like that. The downside though, is that the skeletons are very fragile. To help prevent them from breaking we are planning on encasing them in clear plastic. then we can use them as visual aids for classes and presentations, or just as paperweights, whichever comes first. Because these isopods come from the Antarctic, it is rather hard to get replacements if we ruin these ones, so we have been practicing encasing things in plastic. Thus far we have had... mixed results.

In a recent practice run, we attempted to encase a small crawfish that we bought at the grocery store. We put it in a glass bowl and poured in the (currently liquid) plastic and then put it in a 90 degree incubator to dry.

Crawfish

A little bit of background information about this plastic. It is pretty straightforward. It starts as a liquid, and a catalyst is added. A catalyst is a substance that helps to speed up a chemical reaction. When the catalyst is added the liquid plastic undergoes a chemical change and becomes a solid. As it hardens, it also becomes a little bit smaller (not much, just a little).

Pictured: SCIENCE!

When the plastic becomes fully hardened it is supposed to shrink and pull away from the mould a bit (this is convinenet because it makes it easy to get the plastic out of the mould). So we allowed our encased crawfish to dry for a few days. And then a few more. Eventually the plastic appeared and felt like it was fully dry, but still it didn't pull away from the mould. We eventually contacted the manufaturer for their advice. They were stumped as to why the plastic never pulled away from the mould and reccomended that we simply break the mould to get the plastic out. The bowl was a cheap dollar store glass bowl and was easily replaceable so we decided to give it a try.

We laid down some cardboard to collect any broken glass from the bowl. We put the bowl down and got a hammer and gave it a wack. To our surprise, nothing happened. We hit the bowl a second time, a little bit harder, and still nothing happened. With a little more power, we gave the bowl one more wack.

Now, how many of you have ever heard of Pyrex? It is a type of glass that is used in a lot of glass cookware. It's quite popular because, unlike normal glassware, it is virtually unbreakable. But when it breaks, it breaks a lot. 

Pictured: Broken Pyrex.

As you probobly have already guessed, our bowl was in fact made of Pyrex. To say that the last hammer hit broke the bowl is a bit of an understatment. A more accurate word would be disintergreated, shooting tiny shards of glass all across the lab.

Unfortunately, the glass didn't absorb the full force of the hammer, and the plastic encasing the crawfish cracked.

As it turned out, the plastic did shrink a little bit. It didn't shrink enough to pull away from the mould, but it did shrink enough to put some pressure on the crawfish. Also, as it turns out, if a fish is kept for a long period of time at 90 degrees, even if it is encased in plastic, it still spoils. So as soon as the crack in the plastic appeared, the pressure on the craw fish had an escape route, so up through the crack squirted a fair amount of rotten craw fish juice.

There is a reason you have never seen this flavor.

But apart from ruining the plastic embedment, covering the lab with broken glass and making everything smell like a poorly maintained fish market, things went pretty well. We are now working on the real deal and will post pictures just as soon as we are done.


Once again, if you would like to see more about Giant Antarctic Isopods CLICK HERE!

By Ben Segee