I use this brief chapter from the book Doing Biology by Joel B. Hagen to provide a broader historical context to our discussion about ecology and classification. Whittaker's work in connecting how organisms obtained nutrition and how that could be used to create a usable classification scheme is an interesting read that connects many different topics of study we have worked together on this year. I also like that it brings in a secondary text that allows us to practice close reading skills together. Many teachers choose to skip this type of lesson but I have found that my students retain and connect the many fields of biology in a much more substantive way and I attribute that in part to the work we do together to make those links explicit and to give them time to have conversations about them. You may have noticed that I include secondary text source lessons as part of each of our units in this biology class and although it does require more class time together to work through the material we are studying, the cumulative impact of this type of time and attention to reading comprehension, vocabulary building, and collaborative and individual reading strategies has been powerful as I measure their assessment writing skills and observe the complex nature of student driven projects I have received this year.
I also like this Whittaker story because it can flow into a bigger conversation about the many other ways to classify organisms and why you might choose one classification scheme over another, the idea that accuracy is only one piece of the puzzle and that whatever scheme you choose has to be functional/usable and match the goals of the area of study in question. Another secondary theme I like to bring up with students if they don't come to it on their own is that this is yet another story about a scientist working outside of his chosen field in a way that brought new perspective and insight that led to a lasting shift in thinking by scientists in that field. Watson and Crick are two other scientists that worked outside of their fields of expertise to create the most influential DNA discovery of their time! I believe it is always important to demonstrate to students how each one of us can contribute to discussions of big ideas from our own unique perspective in ways that can significantly impact our community understanding of those ideas. I have also used readings from this book to support student research projects about Lynn Margolis' endosymbiotic theory among others.
1. Tell students that today you will be investigating the history of how we classify living things. Pass out the Doing Biology reading and the Robert Whittaker and the Classification of Kingdoms guiding questions document.
2. Announce to students that they will be working with a partner to read, annotate, discuss, and answer the questions about the ways in which classification of organisms shifted over time.
3. Ask students to group themselves with a reading partner and find a place in the room to get settled. Assist any students that seem lost or unsure about partner choices.
2. Allow students time and a quiet space so that they can read, annotate, and reflect upon their chosen article.
3. I do not collect student annotation notes; my philosophy is that those are for them to have and refer to as needed. The assessment piece for me is their guiding questions document, which they create with their partner and turn into me for grading later on in the week.
1. Ask students to get into groups of four (two pairs of reading partners) and consider the following prompts:
What sticks out to in this reading you as interesting or important?
What ideas need further review or clarification?
Do you agree that an ecology based classification system is the best one to use or is there another way you think we should be organizing living things in categories?
2. Use the spokesperson protocol to share out group responses.
3. Draw out a summary diagram of our tree of life. See my whiteboard drawing for ideas. Students will be very interested to see how it has shifted, not only from the 2-6 kingdom classification scheme they read about in their article, but also in our newer understanding of the relationship between archeabacteria, (eu)bacteria, and all of the eukaryotes. This step really helps students link together their prior knowledge to this newer exploration of classification, taxonomy, and phylogeny.
4. Address any clarifying questions before the period ends. Remind students of their guiding questions document deadline.