22 December, 2002

Back from the field and checking for yeast

When we return from the second transect soil collection, we are all anxious to see what is growing on our plates in the incubator. We are hoping for lots of colonies. but, much to our disappointment we found very few colonies growing. It is time for a lab meeting. This is a time when we all get together, look at what we have and problem solve. We go over the protocol and check the recipe for the yeast food. Then we speculate about what might be happening. What do you think? Do you think that there are just not many organisms in the soils? What should we do? Talk with your friends about our problem.

Here are some of the things we consider, and what we decide to do. Remember that we collected a lot of soil.

Ideas as suggestions are made - here are some of them

Maybe we need to do the samples again with more soil

Maybe we need to shake the soil longer and or harder in the water Maybe the soil sample needs more space

Maybe the pre-filter caught the organisms

Check on the size of the profiler pores

We remember that yeast is about 1 micrometer in length - If the pre-filter is too fine, it will catch all of the organisms and not let them through But, if we use a larger pore filter, we get lots of soil on our filter Maybe we need a different temperature

Can we use those prefilters that we saved - I guess not since they have been in the lab at room temperature too long

Remember, we made up our methods from reading research papers. This is an example of how science works. It is never a smooth process, but rather a matter of looking at what happens and moving forward from these.

Here is what we decide to do. We will reprocess the samples again and process the new samples. We will use 100 grams of soil rather than the 20 grams. We will shake the samples in a shaker for a much longer period of time. and we will use larger plates - we will use regular sized petri dishes if the supply people have enough for us to use. This might be a problem because we had not thought that we would need a lot of the bigger plates. With a new plan in mind, we all have lots of work to do in the lab this week and before we set out to collect the third transect in the Taylor Valley.

We make more media (yeast food), pour the plates, and process all of the samples.

We the take some time to look carefully at the colonies that we do have. We need to refer to research papers to help identify the organisms that we find on the plates.

It is near Christmas and everyone is tired. after the new plates are all in the incubator, we we have a bit of time to relax and enjoy the holiday and the excellent food prepared by the chef at the dining hall. There is a wonderful Christmas program and party for everyone.

Soon it is time to plan the third collection of soils, this time in the middle of the Taylor Valley. By now you know what we need to do

Helo information gathering

Food selection and weighing

Personal gear packing

Hoping for good weather

Establishing collection spots using the GPS

Deciding where to camp