Constant Temperature- or not as the case may be

In Freshwater Ecology we are currently working on group projects- my group is researching freshwater snail habitat preferences. This involved us going down to a creek on Monday afternoon and collecting 200 tiny freshwater snails to put 20 each in 5 replicates of 2 treatments.

The different treatments were temperature differences. One lot of snails we placed in the 5 degree constant temperature room and the other in the 15 degree constant temperature room.

We (foolishly) expected that "5 degree constant temperature room" meant that the temperature would remain constant at 5 degrees, but when we were checking the snails the next morning ice had formed on the surface of the water, and today they had frozen solid.

So unless these snails are able to withstand freezing (we will find out when they have thawed tomorrow) we now have to collect another 100 snails and restart the experiment-this time using a refrigerator instead of the constant temp room.

It also turns out that the 15 degree constant temp room is actually 22 degrees, but that is a little less disasterous for the snails.

Its a very good thing that we are only undergrads working with very common snails, because if some of the postgrad researchers accidently froze their animals there would be huge problems- and very annoyed researchers.