24 October 2022

2022 version of Cefni foraminifera analysis

 Through the years, what I have made the students on our third year fieldwork module do with foraminifera  has changed a lot. It started how my predecessor James has designed the assignment: take the students into the field in the morning, make sure they process the samples before lunch, bung the samples in the oven, and then have them pick and count 100 specimens after lunch. Sometimes they weren’t finished until 9 pm. And the sampling in the morning was tide dependent, so that sometimes started before 5 am. Those were heavy days!

When, for financial reasons, the field trip had to become shorter, I was given less time. And I basically couldn't really make the students do any assemblage analysis anymore. It felt like the whole exercise was becoming a bit pointless because of that. But then everything changed when the pandemic hit. The first year we had to do the whole field trip online. It was far from ideal! But we made the most of it.

Then last year we went in person again, but now in the north. And with severe restrictions on how we could transport students. Suddenly, we had to transport all the students at the same time. That meant I had to drag all the students into the field, make them all do various activities, and then ship them back to Bangor. That meant I had to bunch many activities into each day. You need to keep them all occupied! But there is only so much we need to do in the field, so I basically just claimed one day in the lab in the middle of the field trip.

This year we could use more vehicles again, so we could just bring the students that were scheduled to do something into the field, and leave the rest where they were. So we could spread things out again! And that meant that we were in the field every single day. I had asked Martin to give me a day in the lab afterwards. That seemed much more suitable; just do that assemblage analysis during the actual term! And that day came. It also meant we were back doing a full day of micropalaeontology in the lab; something I had got rid of in one of my other modules, as it is too much for one person to supervise, and I am the only one in the School who can do this. Katrien is very helpful, but she has never worked with forams, and sometimes misidentifications sneak in! And that can do strange things to your dataset. 

The practical was scheduled from 9 to 3. That should be doable! The samples were ready. I made sure I was there fairly early so I could make sure all was set up. And at nine, Katrien appeared. She tends to be my assistant in these things! But she had to leave early, and that was a pity.

I first explained to the students how you adjust and work a microscope. They might not have worked with low power microscope before! And if you don't point things out to them, then sometimes they are unaware of basic things such as how to zoom in. That's very important with foraminifera analysis! 

I also explained to them that I wanted them to pick an identified split of their sample. It wasn't important how big the split was; 1/2. 1/8, 1/128; doesn't matter, as long as they ended up with neither too many nor too few forams. I wanted them to try to get to 100. So I suggested they try to first establish how abundant the forams in their sample were. And then try to create a split that does indeed have some 100 forams. And then I got them picking.

After a while I also told them a little bit about how you identify foraminifera. That is the interesting part! But it takes awhile. And we had 20 students there.

With Katrien leaving just under those about to become very busy I quickly realised that we would not manage to have all the counts checked before the practical was over. I had a quick think. I then suggested that the students that they spent the last minutes of the practical making sure all their materials properly labelled. And then to stand both their list with identifications, and that my growth with the foraminifera on them to me. And their sample bags with the various splits. Then I could just check their identifications in my own time, and give them the complete dataset back ASAP. And they thought that was okay!

A few students decided to have their counts checked there and then. Generally they had done well! And then they left, and it was up to me to collate all the materials. And I was not overly impressed! The sample labelling was not what I hoped it would be. There were microslides and lists without a name; there were microslides and lists without a sample number. There were lists and samples with sample numbers I knew were wrong. And if you don't know which some sample is which, you can't use these samples!

In the following two days I went through all these samples. It was actually quite pleasant to do! Sometimes I could check the identifications specimen by specimen. That is ideal; then you know if there is a particular species a student might struggle to identify. But in some samples, the specimens weren't properly stuck down to the cardboard (an indication of insufficient glue having been used), the specimens had moved around and the only thing you could check was the total numbers. That still gives you a good idea, though!

The Friday of that week I published the full set; both the modern ones from the practical, and the fossil ones I had picked myself. I think I need to ask timetabling to insert a lecture to help with the students on their way making sense of this. But I will also emphasise good labelling practice! A sample is often something you have spent quite a lot of time (and sometimes money) on; you don't want to then not be able to use it.

Soon we will put the data to the test; can we derive in what environment the various units we found in the sediment core were deposited? I sure hope so! 


All forams still in place!

Forams have moved...

Attempt at photographing an E. williamsoni with algae in its test with an iPhone

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