Illustrating the Process of Science Using Leaf-Margin Analyses

Tuesday 1:30pm-2:40pm Burge Union Forum C/D
Share-a-Thon Part of Share-a-Thon Presentations


Wendi J. W. Williams, South Texas College


Fundamental information provided by the Smithsonian Institution learning materials adapted using Universal Design of Instruction to maximize visual materials for Persons with Disabilities. Examples of how implemented in various teaching modes (in person hybrid and online suggestions). Discussion of how modelling this type of modifications and also the content is appropriate for education broadly that better includes varied learning abilities as well as best practices for pre-service teacher candidates in core STEM sections. Tagged to NGSS.


The activity is derived from a Smithsonian Institution Middle to High School lesson distributed approximately 10 years ago using Leaf-Margin Analyses on fossil leaves from Wyoming, U.S. (based on work by Dr. Scott Wing and others). The activity uses high resolution images of fossil leaves from deciduous trees just before and during the Paleocene - Eocene Thermal Maximum (PETM). Students use these images to acquire data, calculate average annual air temperature for two stratigraphic localities (representing different ages), then put into the context of "then and now." In terms of my community college's seven general education outcomes, this modified activity easily helps addresses four: develop higher order thinking skills, achieve mathematical literacy, use computers proficiently, and employ a variety of sources to locate, evaluate, and use information. My adaptations are in having modified materials for Universal Design* and how the activity is pedagogically implemented. *With multi-modal modifications to include Persons with Disabilities.


I have used this activity for core-level, mainly non majors introductory geoscience and physical science courses. Sometimes as a "lab" and other times as a "lecture" activity (hybrid/in person and online sections) as a case study of Process of Science (coupled with VisionLearning coverage of POS) illustrating cross-disciplinary teaming to study a paleo-ecosystem. I often use this when our topical schedule gets to geologic time, in order to have students first know enough about the rock cycle processes and products and to also bring climate changes into the discussion.

Why It Works

I have been using this now for at least 5 years, and it never fails to engage small groups -- not only interest level goes up but deeper connections and discussions occur. Using this ~ mid-way in the term allows me to bring earlier Process of Science- and Earth Science Literacy Initiative-based activities from the first two weeks of our 16-week term back into the learning module for geo-time. My modification for Universal Design includes taking a learner-centered approach that expands upon concepts through event sequencing; observational data collection; mathematical reduction, graphical representation and evaluation; and synthesis.