Assignment 13
Evidence of Change In 
Living Things Over Time
 

Adapted from:  What On Earth Is Evolution?  The Geological Perspective of Teaching Evolutionary Biology Effectively,
               by Abour Cherif, Jerry Adams, and John Loehr (2000) 

 
 
Up until this point, you have been investigating the processes of determining the age of the Earth, determining the importance of fossils to learning about prehistoric organisms and tracing the change of species over time.  During previous assignments, you examined  the process of natural selection first-hand.  Remember that the actual processes of natural selection and evolution take place over long periods of time and we are rarely capable of observing these processes directly.  As you have seen, the fossil record is a valuable tool scientists use to observe the process of evolution; however, the fossil record is not the only evidence scientists have discovered that makes it possible to determine if a process has taken place. 

In this assignment, you will look for more evidence of change in living things over time.  The class will be divided into six groups.  Your Instructor will assist you in establishing your groups.  Each group will be assigned a topic to investigate from the following list.

Cytology - This group will search for cytological similarities and differences among living things.  Members of this group may find the cell theory to be a good place to begin their investigation.

Biochemistry - This group will search for biochemical similarities and differences among living things.  Possible investigation topics may include nucleic acids, genes, proteins, and enzymes. 

Anatomy - This group will search for anatomical similarities and differences among living things.  Members of this group may find the term "homologous structures" to be a good place to begin their investigation. 

Embryology - This group will search for similarities and differences in the early embryonic development among living things.

Geographic Distribution of Species - This group will search for similarities and differences between certain island groups, called oceanic islands, that arose from the ocean floor and have never been connected to continents (Hawaii, Tahiti, Galapagos, etc.)

Direct Observation - This group will search for changes that can be seen as they occur in living species.  Members of this group may want to begin their investigations with the peppered moth (Biston betularia) and animal breeders.

The groups will be given all of the remaining portion of today's class and until next week's class to conduct research on their topic and to develop a presentation to deliver the information they uncover to the rest of the class.  As you conduct your research, remember that the theme of each group is "Evidence of Change in Living Organisms Over Time."  Make sure that your presentation focuses on that theme and includes all information relevant to the topic.  Presentations are to be delivered using a projector and Power Point slide show as the medium.  Presentations should be between 8 and 10 minutes in length.  Because there will be several presentations to deliver during our next meeting, so time limits will be enforced.  You may choose to have more than one presenter, or delegate work so that some group members construct the presentation while others deliver it.  Every member of the group is expected to contribute equally to the success of the presentation.  Be sure to rehearse your presentation in order to ensure you will be able to deliver your presentation effectively in the allowed time.