HS-LS4-4 Construct an explanation based on evidence for how natural selection leads to adaptation of populations.
Clarification Statement: Emphasis is on using data to provide evidence for how specific biotic and abiotic differences in ecosystems (such as ranges of seasonal temperature, long-term climate change, acidity, light, geographic barriers, or evolution of other organisms) contribute to a change in gene frequency over time, leading to adaptation of populations.
Assessment Boundary: none
This resource is explicitly designed to build towards this performance expectation.
Tips for Including the Performance Expectation
At the beginning of the lesson, students place four illustrations showing different numbers of light and dark colored rock pocket mice at two locations (light/dark substrate) in sequence from oldest to most recent. Watching the short film, students learn about the changes of rock pocket mouse populations, and that the environment contributes towards determining whether or not randomly arising mutations in fur color are advantageous, neutral, or deleterious. As students return to the four illustrations after watching the video, they analyze the illustrations by counting and graphing the color distribution of rock pocket mice at the two locations (light/dark). Based on this evidence, students arrange the four illustrations in a sequence from oldest to most recent, and make an argument for how natural selection leads to a change in fur color in the populations of rock pocket mice over time. Before starting the activity, it is helpful if the teacher familiarizes students with the rock pocket mouse and its habitat. To engage student interest in the lesson, teachers should raise the question of how there came to be two different populations of pocket mice (light/dark). To get a sense of their initial thinking, students should not skip the step of an initial ordering the rock pocket mice illustrations before they watch the short film. Throughout the activity, students should work with a partner or in small groups and be encouraged to share their thinking as they make decisions about re-ordering their illustrations, graphing the data, and answering the questions.