Objectives (5 - 7 minutes)

• Students will understand the concept of artificial selection, also known as selective breeding, and how it differs from natural selection.
• Students will be able to describe how humans have used artificial selection to modify species over time, leading to the development of new breeds of plants and animals.
• Students will develop an appreciation for the significant impact that humans can have on the evolution of species through their actions.

Secondary Objectives:

• Students will engage in critical thinking and discussion about the ethical implications of artificial selection and the responsibility humans have in shaping the natural world.
• Students will improve their ability to analyze and interpret data, as they will be presented with examples of artificial selection in action.

Introduction (10 - 12 minutes)

• The teacher begins by reminding students about the concept of evolution and natural selection, which they have previously studied. They will ask a few quick review questions to ensure students have a basic understanding of these topics. For example, "Can someone give me a quick definition of evolution?" or "What is the main force behind natural selection?" (3-4 minutes)

• The teacher then introduces two problem situations to the class. The first scenario is about a farmer who wants to create a breed of sheep that produces more wool. The second scenario is about a gardener who wants to develop a type of flower that has a unique color pattern. The teacher asks students to think about how these individuals might achieve their goals. (3-4 minutes)

• To contextualize the importance of the subject, the teacher shares two real-world applications of artificial selection. The first example could be about how modern agriculture relies heavily on artificial selection to produce high-yield crops and livestock. The second example could be about how dog breeds have been developed through artificial selection, resulting in a wide range of characteristics from size and shape to personality traits. (2-3 minutes)

• To capture the students' attention and spark their interest, the teacher shares two intriguing facts related to the topic. The first fact could be about how certain fruits and vegetables we commonly eat, like corn and broccoli, were originally wild plants that were drastically changed through artificial selection. The second fact could be about how some species, like pigeons and goldfish, have been bred for specific traits to the point where they look nothing like their wild ancestors. (2-3 minutes)

Development (20 - 25 minutes)

1. Definition and Explanation of Artificial Selection (5 - 7 minutes)

   • The teacher presents the main topic of the lesson: artificial selection. The teacher explains that artificial selection is the process by which humans select and breed individuals with desired traits over many generations, leading to the evolution of new breeds.
   • The teacher uses an intuitive explanation to make the concept more accessible to students. For example, the teacher could say, "It's like when you pick the best crayons from a box and only use those to color. Over time, the box will have only those colors left because you keep 'selecting' them."
   • The teacher emphasizes the difference between artificial selection and natural selection: artificial selection is guided by human choice, while natural selection is driven by environmental factors.

2. Agricultural Applications of Artificial Selection (5 - 7 minutes)

   • The teacher explains how artificial selection plays a crucial role in modern agriculture, allowing farmers to produce crops and livestock with higher yields, increased resistance to diseases, and improved nutritional content.
   • Examples of agricultural applications could include the development of seedless fruits, high-yield crops like wheat and corn, and the selective breeding of livestock to improve meat or milk production.
   • The teacher uses visual aids, such as pictures of different breeds of fruits, vegetables, and livestock, to illustrate the dramatic changes brought about by artificial selection.

3. Artificial Selection in Animal Breeding (5 - 7 minutes)

   • The teacher transitions to the topic of artificial selection in animal breeding. The teacher explains that humans have used selective breeding to create a wide variety of dog breeds, each with distinct physical and behavioral traits.
   • To illustrate this, the teacher can show pictures of different dog breeds and discuss how they were developed for specific purposes, such as hunting, herding, or companionship. The teacher can also discuss the potential downsides of extreme selective breeding, such as health problems in certain breeds.
   • The teacher further highlights the ethical considerations involved in artificial selection, such as the potential for cruelty and the importance of responsible breeding practices.

4. Artificial Selection in Horticulture (5 - 7 minutes)

   • The teacher then delves into the topic of artificial selection in horticulture. The teacher explains that gardeners have long used selective breeding to create new varieties of flowers and plants with unique colors, shapes, and sizes.
   • The teacher could show pictures of wild and domesticated plants side by side to illustrate the dramatic changes brought about by selective breeding.
   • The teacher can also discuss the role of artificial selection in the development of genetically modified organisms (GMOs) and the controversy surrounding their use.

Throughout the development stage, the teacher encourages students to ask questions and participate in discussions about the topics presented. The teacher also uses formative assessment techniques, such as quick quizzes or group discussions, to ensure students are understanding the material. By the end of this stage, students should have a solid understanding of what artificial selection is, how it differs from natural selection, and how it has been used in agriculture, animal breeding, and horticulture.

Feedback (8 - 10 minutes)

• The teacher begins the feedback stage by summarizing the main points of the lesson. They highlight the definition of artificial selection, its role in human evolution, and the ways it is applied in agriculture, animal breeding, and horticulture. They also reiterate the ethical considerations related to this topic. (2 - 3 minutes)

• The teacher then connects the theory with practice by proposing a few reflection questions. These questions are designed to encourage students to think about the lesson's content from different perspectives and to apply their knowledge to new situations. For example:

  1. "Can you think of any other situations where humans might use artificial selection in the future?"
  2. "What might be some unintended consequences or risks of using artificial selection?"
  3. "How do you think artificial selection could impact biodiversity?" (3 - 4 minutes)

• The teacher invites students to share their responses and encourages a class discussion. They should ensure that all students have an opportunity to participate, either by sharing their thoughts or by asking questions. The teacher provides feedback on students' contributions, corrects any misconceptions, and praises well-reasoned responses. (2 - 3 minutes)

• To conclude the feedback stage, the teacher asks students to reflect on what they have learned. They are asked to think about the most important concept they learned today and the questions they still have. This reflection can be done silently or in a brief writing exercise. The teacher can collect these reflections for review and to guide future instruction. (1 - 2 minutes)

Conclusion (5 - 7 minutes)

• The teacher begins the conclusion by summarizing the main points of the lesson. They reiterate the definition of artificial selection, its role in the evolution of species, and its differences from natural selection. They also recap the examples of artificial selection in agriculture, animal breeding, and horticulture that were discussed during the lesson. The teacher emphasizes the profound impact that humans can have on the natural world through their selective breeding practices. (2 - 3 minutes)

• The teacher then explains how the lesson connected theory, practice, and applications. They highlight how the initial theoretical concept of artificial selection was brought to life through practical examples in agriculture, animal breeding, and horticulture. They also discuss the ethical considerations that were explored, helping students understand the real-world implications of artificial selection. The teacher reinforces the importance of understanding these concepts for their future studies in biology and for their roles as informed citizens. (1 - 2 minutes)

• To further students' understanding of the topic, the teacher suggests additional materials for self-study. These can include articles or videos about the history of artificial selection, its role in the development of modern agriculture, and the controversy surrounding genetically modified organisms. The teacher can also recommend books or documentaries about the broader topic of evolution, providing students with a more comprehensive understanding of the subject. (1 minute)

• The teacher concludes the lesson by discussing the relevance of artificial selection in everyday life. They explain that artificial selection is not just a historical concept, but a current practice that impacts our food systems, the animals we interact with, and even the flowers in our gardens. Understanding artificial selection can help us make informed decisions about the products we consume and the practices we support. Furthermore, the teacher highlights that the ethical considerations raised by artificial selection are not only relevant to biologists, but to all citizens who have a stake in the health of our planet and its biodiversity. (1 - 2 minutes)