Predator Sense and Prey Defense: A Lab Exercise in Evolutionary Hypothesis Formulation and Experimentation

 

Tested Studies in Laboratory Teaching, 2013, Volume 34

Cindy Bennington, Rachel Burnett, & John Jett

Abstract

This open-ended laboratory exercise was designed to improve students' ability to formulate and test evolutionary hypotheses. Presented over three weeks, students first read a short scientific paper that described the results of a prior experiment conducted by the instructor(s) designed to investigate the evolution of distastefulness in prey species, then developed a testable prediction related to the evolution of distastefulness that could be answered using domestic crickets and field-caught wolf spiders. Laboratory exercises related to understanding the power of natural selection are often limited to physical or computer simulations. Our open-ended approach, which allows students to create phenotypic variation (i.e., manipulate cricket palatability through the application of distasteful substances) and to measure fitness (i.e., cricket survival in the presence of a generalist predator) provides students with a dynamic illustration of selection using real organisms.

Keywords:  evolution, hypothesis testing, natural selection, Hogna

University of North Carolina, Chapel Hill (2012)