Vertebrate Phylogeny

Written by Kelly A Hogan, University of North Carolina at Chapel Hill

Learning Outcomes:

– To describe how phylogenetic trees show evolutionary relationships

– To describe shared characteristics in vertebrate evolution

– To construct a simple phylogenetic tree for mammalian evolution

Activity Description: This activity can be used while teaching vertebrate evolution. It will also bring in phylogeny, as a way for students to see relationships rather than lists of characteristics to memorize about vertebrate. Students will explain phylogenetic trees, practice with the vertebrate phylogenetic tree they have seen in their textbook, and then construct their own tree to demonstrate their understanding of phylogeny. After the worksheet, an assessment question (see below) can be used b the instructor in various ways.

Time Needed: 15-20 minutes

Materials Needed: The activity worksheet can be printed for class time. A key is also attached. An optional “Guided Reading Questions” worksheet accompanies the activity for students to do on their own while reading to prepare for this day’s activity.

Vertebrate Phylogeny Worksheet

Vertebrate Phylogeny Worksheet KEY

Guided Readings Questions for Vertebrate Evolution

Activity Instructions: Students should read about vertebrate evolution before this activity. Students work through the worksheet and are then given the assessment below.

Assessment: The following assessment is adapted from an “Applying the Concepts” Question in Chapter 15 of Campbell Biology Concepts and Connections 7th Edition. It can easily be modified into a set of clicker or multiple choice exam questions.

Directions: Arrange the species on the phylogenetic tree below and indicate the derived character that defines each branch point.

Numerous questions can be made for clicker or test exams for students to make correct labels. Example:

What should be at label “Z”?

A)    Fur

B)     Green Skin

C)    Bleeker

D)    Suction Cup Feet

E)     Giant Eyes

Answer: D

Key: for all labels:

W – Green Skin

X – Giant Eyes

Y – Fur

Z – Suction Cup Feet

1- Bleeker

2- Floof

3- Snoozle

4- LooHoo

What Is That Adapted for?

Written by Kelly A. Hogan, University of North Carolina at Chapel Hill

Learning Outcomes:

– To have students appreciate how diversity and evolution are linked

– To discover fun examples of diversity and share them with classmates

– To learn by teaching others

Activity Description: This activity works well within any of the diversity chapters. Students are asked to develop a PowerPoint slide (or voice thread, discussion board entry, etc.) that they will submit to the instructor for presentation. This is easily used in large lectures in which the instructor can choose a few to be presented or students can work in groups to cut down on the number of submissions.

Time Needed: As little as 15 minutes or more depending on discussion

Materials Needed: Students will need access to PowerPoint and the Internet.

Activity Instructions: Each student (or group) will submit two PowerPoint slides. You choose some of these to be presented to the whole class (the students chosen will present them to the class). Students are typically interested in this because their classmates created the material. Yet, to make this more interactive, ask students to write down or yell out answers of what they think the organism is adapted to before the second slide of each presentation. Encourage diverse answers and stress how much fun learning about diversity is in this context.

Instructions for student: You will be designing your own PowerPoint slide in which you show an image of an organism that has what you perceive to be a strange structure or behavior. Please cite the source of the image you use. As a second slide, you will then explain (based on your own research) what that strange structure or behavior adapts the organism to (cite sources of information).

Example:

Slide 1: Why does a camel have a hump? How does it adapt it to the desert habitat?

Slide 2: The hump stores fat (even though most people think it stores water). Since camels can go long periods without food and water, the humps are important energy fat reserves. When the fat is depleted, the hump sags (shown in image):

Photo from: http://www.amazingadda.com/showthread.php?15752-List-Of-Animals/page20

A Chance Discovery of Endosymbiosis? A Case Study

Written by Kelly A. Hogan, University of North Carolina at Chapel Hill

Learning Outcomes:

– To demonstrate evolution in action based on famous endosymbiosis experiments by Kwang Jeon

– To appreciate how scientific discovery is sometimes accidental

– To explore Lynn Margulis’s theory of endosymbiosis and the differences between prokaryotes and eukaryotes

Activity Description: A short case study about two graduate students is used to explore how an accidental bacterial infection in eukaryotic cells can lead to a case of endosymbiosis. Students are asked to research the endosymbiosis theory and think about the evidence to support it. Students should either come to class ready for discussion after completing the activity or time can be given in class to allow students to research with their books and the Internet.

Time Needed: 50 minutes if given time to discuss and research in class (less if students have completed the questions on their own before discussion)

Materials Needed: Internet for student research. Students should be able to compile the information they need from their book and a single website: http://evolution.berkeley.edu/evolibrary/article/endosymbiosis_01

Activity Instructions: Distribute case study and questions to students. Allow them time to research in class and intersperse with discussion and a mini-lecture. Alternatively, have students complete the case study on their own and discuss it in the next class. http://evolution.berkeley.edu/evolibrary/article/endosymbiosis_01 is a wonderful resource and this case study will expose them to this site.

Worksheet: Endosymbiosis Case Study & QuestionsEndosymbiosis Case Study Questions KEY

What Do My Classmates Think About Evolution? What Do Scientists Believe About Religion?

Written by Kelly A. Hogan, University of North Carolina at Chapel Hill

Learning Outcomes:

– To appreciate that there are three major views on evolution

– To correct the misconception that one has to choose between science and religion

Activity Description: Students are polled using a national Gallup poll question regarding evolution. After looking at class data, they are shown national data using the same poll question and asked to draw some conclusions. Lastly, data will be presented to engage students in a prediction followed by a discussion about science vs. religion.

Time Needed: At least 15-20 minutes, depending on time devoted to discussion

Materials Needed: None

Activity Instructions:

1. Ask them a poll question: Ideally, this is done with clickers so that the results are anonymous to the class. In a small class, voting on paper would work too.

Which most closely resembles your current belief system?

A. God created man pretty much in his present form at one time within the last 10,000 years.

B. Man has developed over millions of years from less advanced forms of life, but God guided this process, including man’s creation.

C. Man has developed over millions of years from less advanced forms of life. God had no part in this process.

2. Ask the students to compare the class results with national results. Ask them to comment on the similarity or difference.

3. Ask the students what is different about the class compared to the population polled?

(The class is younger and at a college education level.  The poll would have included young and old with various degrees.)

Next show them more data and ask them to make some conclusions.

(The creationist view decreases with a rise in education level; the theistic and naturalistic views rise with a rise in education level.)

4. Ask them if religion and science are incompatible. If this question was asked to scientists, what do they predict would be the outcome? After their predictions, show them the data below and ask again if science and religion are incompatible.

5. Discuss the misconception that a belief in science excludes a belief in religion. This is an important issue because there is much division in the U.S. about this issue.

a. Th eBerkeley website about evolution is a great place to read more about this:

http://evolution.berkeley.edu/evosite/misconceps/IVAandreligion.shtml

“Religion and science (evolution) are very different things. In science, only natural causes are used to explain natural phenomena, while religion deals with beliefs that are beyond the natural world. The misconception that one always has to choose between science and religion is incorrect. Of course, some religious beliefs explicitly contradict science (e.g., the belief that the world and all life on it was created in six literal days); however, most religious groups have no conflict with the theory of evolution or other scientific findings. In fact, many religious people, including theologians, feel that a deeper understanding of nature actually enriches their faith. Moreover, in the scientific community there are thousands of scientists who are devoutly religious and also accept evolution.”

b. Additionally, the director of the NIH Francis Collins, one of the most influential scientists in the U.S., has been quite outspoken on this issue. He believes that God created life through evolution (and he rejects intelligent design and creationsim). However, Collins chose to use the term BioLogos because of the association of evolution with atheism that occurs in some religious communities. His book, The Language of God: A Scientist Presents Evidence for Belief (Free Press, 2006), spent many weeks on the New York Times bestseller list.

c. Statements from Religious Organizations: http://ncse.com/media/voices/religion

PowerPoint Presentation: What Do My Classmates Think? PowerPoint Presentation