This activity provides an introduction to natural selection and the role of genetic variation by asking students to analyze illustrations of rock pocket mouse populations (dark/light fur) on different color substrates in the Sonoran Desert (light/dark) over time. Based on this evidence, and what they learn about variation and natural selection in the accompanying short film, students use this evidence to explain the change in the rock pocket mouse populations on the lava flow (dark substrate) over time. This is one of several classroom activities, focusing on related topics and varying in complexity, built around the short film. This ten minute film shows adaptive changes in rock pocket mouse populations, demonstrating the process of natural selection and can be accessed at http://www.hhmi.org/biointeractive/making-fittest-natural-selection-and-adaptation. The film is also available as an interactive video with embedded questions, which test students understanding as they watch the film.
This Google Folder leads to an online module that is designed for students to learn concepts of evolution, descent with modification, natural selection, and more. There is both a student guide and a teacher's guide to help navigate through the module. Google forms are also available to support learning throughout the module. Interactive activities and simulations are also included for students to enjoy and learn from.
After studying the basics of enzyme function, students will be exposed to the history and evolution of lactose intolerance/lactase persistence. Both whole group and individual activities will ask students to interact with the concept. They will conduct a lab to understand the role of enzymes in lactose digestion and communicate their knowledge by creating a public health poster.
It is well known that mutation is the ultimate source of variation. Without adequate variation, plant breeding is impossible. To start a breeding program, the breeder must find the appropriate genotype (containing the desired genes) from existing variation, or create the variation if it is not found in nature. Mutagenesis is the process by which new alleles are created. The purpose of this chapter is to discuss mutagenesis as both a technique and a breeding method. The newly created mutants may be used as parents in future breeding programs, in which case mutagenesis is a breeding technique as a source of variation. However, an induced mutant can be systematically processed through conventional breeding steps to be released as a cultivar, hence making it a breeding method (mutation breeding). Mutations arise spontaneously in nature and are pivotal in natural evolution.