Evolution & Extinction (Day 1/2)
Lesson 7 of 11
Objective: SWBAT define evolution and identify evidence of evolution in the geologic fossil record
This is the first day of a two-day lesson that focuses on evolution and how it relates to the biological and geological fossil record. There are some key concepts that students are exploring here:
- Due to changes in genetic sequences, species with advantageous traits were/are more likely to survive and reproduce;
- Most organisms that were alive at one time are not extinct;
- As the fossil record progresses toward the present day, organisms generally (although not always) increase in biological complexity;
- Much of the evidence of evolution comes from the fossil record
This obviously ties in with principles of extinction, which is to be covered in the next day's lesson. In addition to the standard Regents-based practice and textual pieces which are integral parts of the course, students participate in some evolutionary analyses with some different species.
[Note: For embedded comments, checks for understanding (CFUs), and key additional information on transitions and key parts of the lesson not necessarily included in the below narrative, please go to the comments in the following document: Evolution & Extinction (Whole Lesson w/comments). Additionally, if you would like all of the resources together in a PDF document, that can be accessed as a complete resource here: Evolution & Extinction (Whole Lesson)[PDF]. Finally, students may need their Earth Science Reference Tables [ESRT] for parts of the lesson (a document used widely in the New York State Earth Science Regents course) as well.]
Do Now & Introduction
Students come in silently and complete the (attached) Do Now. In this Do Now, similar to the previous day, questions that address a particularly low-scoring standard are reinforced. After time expires (anywhere from 2-4 minutes depending on the type of Do Now and number of questions), we collectively go over the responses (usually involving a series of cold calls and/or volunteers), before I call on a student and ask them to read the objective out loud to start the lesson.
As a general note, the Do Now serves a few purposes:
- It serves as a general review of the previous day's material;
- It is a re-activation of student knowledge to get them back into "student mode" and get them thinking about science after transitioning from another content area or alternate class;
- as a strategy for reviewing material students have struggled with (for example, using this as a focused review for material that they have struggled with on unit assessments or recent quizzes); and,
- It is an efficient and established routine for entering the classroom that is repeated each day with fidelity (I never let students enter the classroom talking. While it may seem potentially severe to have students enter silently each day, this is both a school wide expectation and a key component of my classroom. In many respects, I find that students readily enjoy the focus that starting with a quiet classrooms brings each day).
I start out the lesson with a brief lesson "Hook". I display a PowerPoint slide on the board with a picture of archaebacteria - the most primitive form of life on Earth, and the first to appear in the general fossil record. I ask: "What do you think this is?" Student answers vary, but the general response I point out is that these are our biological ancestors. Every form of present life on Earth is in some way derived form these first organisms, and although we look very different from each other now, we have to think about the process that brought about those differences.
After the hook, there is a brief section of notes in the Evolution Notes section, which is followed by a "quick check" and some a short summative question. We go through this part together as a class, utilizing the "Control the Game" popcorn reading strategy of calling on students at random points int the text to read out loud, while the rest of the class follows along.
After students complete the information for the questions, there are a couple of brief principles that summarize the process of evolution, which students put to use in the last example. Students utilize this information to answer the questions about peacock evolutionary development - this exemplifies that organisms with the traits that help them survive and reproduce are the ones more likely to persist in the changing external environment. Students are given 1-2 minutes to read this information with a partner, before we come back together and discuss.
After the evolutionary example with the peacocks above, students are asked to utilize their notes and their Earth Science Reference Tables [ESRT] for the Evolution Practice. Like always, the questions themselves are pulled from a diverse array of former Regents examinations, and all address concepts covered earlier in the the lesson. Additionally, they're mostly organized to get increasingly more difficult and increase in complexity, which is why the harder questions tend to come toward the end.
In terms of student work habits, I tend to sometimes make this decision in the moment, and as a response of what I know about the students and how they're processing the material on, but I'll either ask them to work independently, in partners, or give them the option. Usually, before starting practice, we tend to go over some steps for self-help ("What should you do if you're stuck?"), and I might reference a previously used multiple-choice or free response strategy in order to build their skills while simultaneously learning content (as an example - one popular one we always use - "If you aren't sure what the right answer is, see if you can eliminate some wrong answer choices"). I tend to circulate for compliance and then hone in on specific students while they're doing this.
After about 10 minutes, we go over their responses. We use a combination of strategies (active voting, cold calling, popsicle sticks, volunteers) to go over the responses, where students correct their work and ask any clarifying questions.
Given that this is a two-day lesson, there is no exit ticket as there is most days. I usually give students an extra minute or two to work on their practice, and then we end class the same way we usually do. I give students time to pack up their belongings, and I end the class at the objective, which is posted on the whiteboard, and ask students two questions:
- Do you feel that you mastered the objective for the day?
- Can you reiterate one thing you learned about ____________ (in this case, something about the principles of evolution or how organisms adapt and/or change in their environments, etc.)
Once I take 2-3 individual responses (sometimes I'll ask for a binary "thumbs up/thumbs down" or something similar), I have students leave once the bell rings.