Macroevolution: Patterns, Trends, and Rates of Change

In this lesson, students will learn that some evolutionary change is rapid and discontinuous, and some change is gradual; how fossil evidence can provide clues to the past; and how speciation may account for evolutionary branching and diversification. Fossil shells of a land snail are arranged by layers of age into a sequence pattern suggesting gradual change, or punctuated equilibria. Students will develop a graph showing possible phylogenetic relationships over time of the organism. A variation of the lesson plan uses caminalcules in place of fossil shells. Educational levels: High school