Macroevolution – Post Teaching Reflection
November 24th – Guest Lecture – Biology 336, Fundamentals of Evolutionary Biology
The first guest lecture I gave this semester was on “Sexual Selection,” a topic on which I am quite familiar. This I think may have served as both a help and a hinderance. Because I was familiar with the course material, I dove into numerous examples without focusing on the broader course concepts (i.e. tying the specifics of each example into the content framework). In contrast, I am not an expert on the topic of “Macroevolution”. Giving this guest lecture required a significant amount of prep time, and as such, the examples I used were used to complement the course content, instead of to drive it. As such, I think this lecture did a better job of aligning to some of the course learning outcomes, but I do feel that a stronger background in the topic would have allowed me to be more creative with content delivery.
Class Design:
Unlike my first lecture, I asked to see my mentor’s presentation prior to developing my lecture. I thought this would help to ensure that I was including essential course material. I think that for this lecture, it was immensely helpful to have an example of how the lecture was structured. However, I did find it more difficult to brainstorm ways to change the content and delivery. One of my primary focuses was to ensure that my lecture outline was aligned with that of my mentor’s. This was a bit of challenge, as the previous outline included additional content to be covered in another lecture. One of the primary challenges was working out what to include, and how to build on the complimentary material in the previous lecture.
Challenge Accepted:
In my previous guest lecture I gave myself two challenges. The first was to incorporate a varied pace into my lecture, leaving space for learners to think through questions. I think I significantly improved on my pace this time around, making sure to provide students with time to fill in their class outline and reflect on class questions. I also challenged myself to define any terms that might be new or not common knowledge. This can be extremely hard when you aren’t sure where the baseline vocabulary is for a discipline, but my mentor agreed that there were not any undefined terms in this lecture so I will call that a win.
New Challenges and Lessons Learned:
Lesson 1: Discussion time – I have a hard time conceptualizing how long students need to discuss a question. I thought that 3-4 minutes would be a good amount of time, but quickly realized that they only needed 1-2 minutes at most. After about 1 minute I could tell that the class was starting to have discussions not related to the question and I was losing their attention.
Come-to-Science Moment: Time for discussion is going to depend on the question being asked, but for fairly simple or straightforward questions, I likely need less time than I think I do. This extra time can be allocated elsewhere.
Lesson 2: Too many questions – I feel strongly about engaging the class in a dialogue around course content. In this lecture, I posed a number of questions to the class and it was obvious fairly early on that some students were more willing to contribute than others. I also found that after a few questions, response time increased. This was not likely a result of question difficulty. It seemed that learners became resistant to answering questions after a few minutes. I found this curious. It was difficult to decipher whether students were uncomfortable or whether I was simply losing their attention. My mentor noted that for this point in the term (near exams) I was asking more questions of the class than they will typically ask, perhaps for this reason.
Come-to-Science Moment: More questions is not necessarily better. Further, a greater number of questions posed to the class does not ensure greater class engagement. This might be something I need to be more aware of as I am teaching. This was certainly an instance that highlighted the importance of being able to “read the room”.
Lesson 3: Following up on questions – In this lecture I used more clicker questions than I had previously. This was an attempt to incorporate more opportunities for active learning and to assess how students were understanding the material. For the most part, the questions went well and I have certainly become more comfortable using clicker questions. However, for one of my questions, I missed an opportunity to engage in a classroom discussion. I posed the question “What could explain this pattern of biodiversity”. Students answered that it could be that in the tropics there is either an increased origination rate or decreased extinction rate. Having concluded that students answered the question correctly, I moved on. My mentor noted however that there seemed to be some interest in the class to discuss this concept more. Why do we see those patterns? What characteristics of the tropics might lead to this? This was an excellent observation and I view it as a missed opportunity. 
Come-to-Science Moment: In paying a certain amount of attention to getting through the lesson material on time, I lost an opportunity to have a discussion with the learners in the class that could have been motivational for their learning. In future I am going to pay closer attention to instances when these opportunities arise and I’m going to grab them and run with them.
Lesson 4: Participatory learning activity falls flat – I had an idea. I wanted to show students how species diversity changes through time by focusing on certain groups of organisms, and illustrating that the composition of organisms on earth is a constantly shifting kaleidoscope. To do this, I decided to do a sort of “March Through the Phyla” indicating groups that thrived in certain periods, and discussing how mass extinction events precipitated change. This activity ended up taking longer than I expected (20 minutes) and ended up missing the aim of the activity. I think students left with the idea that they had to memorize what organisms were most diverse and when, instead of taking away the main learning objective which is that diversity changed through time as a result of extinction and origination events.
Come-to-Science Moment: In reflection, I could have achieved this objective by synthesizing this 20 minute activity into one slide. It would have taken some time to develop, but by plotting relative diversity of a few groups throughout the millennia and in relation to mass extinction events, students might have better visualized the rises and falls in diversity through time without focusing on memorizing the minutia.
Lesson 5: Displaying graphs – I usually pride myself in creating some very aesthetically pleasing power point slides. I spend a lot of time choosing colourful photos and placing them perfectly within the text. This time I failed to notice that several of the graphs I presented were too small for students to be able to read on the slide.
Come-to-Science Moment: In future I am going to make sure that graphs are over 1/4 the size of the screen. Bigger is better. I can put the graph on a separate slide if necessary and then come back to the lecture notes.
Next Steps:
The next guest lectures I will be giving are on February 17th, back to back. For my next lesson I am challenging myself to pay particular attention to the learning objectives for the lesson to design an activity that achieves the objective without incorporating additional material that might be distracting. I am also going to make an active effort to ensure that any images I am including to illustrate the core course concepts meet the 1/4 slide size minimum.