This lesson will help students understand how wild species cope with changing factors in their environment, such as new predators, fewer available resources, more difficult access to mates, and variable weather. The interaction of all of these factors, coupled with the gradual nature of the changes that result, make evolution a complex subject to study. With these hands-on labs, students delve into realistic, yet simplified, models of the natural world. They complete a hands-on lab simulation of natural selection. In the first activity they learn how natural selection influences a breeding population of rabbits. This will help them understand natural selection and what genetics can tell us about the evolution of a population of organisms. In the second activity students will replicate a real experiment and examine the interplay between selection factors in a population of guppies. Each activity has a list of objectives and links to detailed instruction. The lesson also offers links to an assessment rubric, the national science standards for the lesson, and additional activities.