Ancestors

What we did:

1. Thought about how to infer properties of ancestors, when we know the properties of the descendants and the phylogenetic tree that connects them. This can be seen as learning to think as scientists, rather than as learning what scientists have found out.

2. Considered properties that might be shared by all cells. Not surprisingly, many students hadn't yet learned to include Bacteria and Archaea in their thinking about life. I wonder if the students who have taken Biology 112 were the ones who had?

3. Considered how the first cell could have evolved. It's difficult to be very specific, given how little scientists know about this, and difficult to be very thought-provoking, given the little exposure many of the students have had to molecular biology.

What we didn't do:

1. Use the clickers. The PRS software froze up when trying to create a PRS 'lesson' within PowerPoint even though it had worked fine on my computer this morning. To make matters worse, it also worked fine after class, when I tried to demonstrate the problem for the technician from Classroom Services. I suspect it was due to some changed setting on the podium PC that had returned to its default when I rebooted the computer. I'll come in on the weekend and check that Monday's questions are going to work.

2. Spend enough class time on student-thinking problems. I think this will be easy once we're into real genetics, but for next week I'll see if I can come up with a few thought-provoking ones.