HR: 0800h
AN: ED51A-0126    [Abstracts]
TI: Using Fossil Shark Teeth to Illustrate Evolution and Introduce Basic Geologic Concepts in a High School Biology Classroom
AU: * Agnew, J G
EM: jagnew2@lsu.edu
AF: Louisiana State University, Department of Geology and Geophysics, Baton Rouge, LA 70803, United States
AU: Nunn, J A
EM: gljeff@lsu.edu
AF: Louisiana State University, Department of Geology and Geophysics, Baton Rouge, LA 70803, United States
AB: Shell Foundation sponsors a program at Louisiana State University called Shell Undergraduate Recruitment and Geoscience Education (SURGE). The purpose of SURGE is to help local high school science teachers incorporate geology into their classrooms by providing resources and training. As part of this program, a workshop for high school biology teachers was held at Louisiana State University in Baton Rouge on June 3-5, 2007. We had the teachers do a series of activities on fossil shark teeth to illustrate evolution and introduce basic earth science concepts such as geologic time, superposition, and faunal succession and provided the teachers with lesson plans and materials. As an example, one of our exercises explores the evolution of the megatoothed shark lineage leading to Carcharocles megalodon, the largest predatory shark in history with teeth up to 17 cm long. Megatoothed shark teeth make excellent evolutionary subjects because they have a good fossil record and show continuous transitions in morphology from the Eocene to Pliocene. Our activity follows the learning cycle model. We take advantage of the curiosity of sharks shared by most people, and allow students to explore the variations among different shark teeth and explain the causes of those variations. The objectives of this exercise are to have the students: 1) sort fossil shark teeth into biologically reasonable species; 2) form hypotheses about evolutionary relationships among fossil shark teeth; and 3) describe and interpret evolutionary trends in the fossil Megatoothed lineage. To do the activity, students are divided into groups of 2-3 and given a shuffled set of 72 shark tooth cards with different images of megatoothed shark teeth. They are instructed to group the shark tooth cards into separate species of sharks. After sorting the cards, students are asked to consider the evolutionary relationships among their species and arrange their species chronologically according to the species first appearance in the fossil record. This is followed by a group discussion of each group's predictions. Next students are given photographs of teeth from different megatoothed sharks, and a geologic time scale with the sharks stratigraphic ranges. Students are asked to describe evolutionary trends in the fossil megatoothed lineage and formulate several hypotheses to explain the observed evolutionary trends. The exercise is concluded with a discussion of the environmental and biotic events occurring between the Eocene and Miocene epochs that may have caused the evolutionary changes in the megatoothed shark's teeth.
DE: 0805 Elementary and secondary education
DE: 0820 Curriculum and laboratory design
DE: 0830 Teacher training
DE: 0845 Instructional tools
DE: 0855 Diversity
SC: Education and Human Resources [ED]
MN: 2007 Fall Meeting