Objectives (5 - 7 minutes)

The teacher will:

1. Clearly define the learning objective to the students which is to understand and differentiate between the theories of evolution proposed by Charles Darwin and Jean-Baptiste Lamarck.
2. Explain that by the end of the lesson, students should be able to:
   • Describe the basic principles of Darwin's theory of natural selection and Lamarck's theory of evolution.
   • Compare and contrast the key differences between Darwin's and Lamarck's theories.
   • Identify the impact of these theories on our understanding of biological evolution.
3. Mention that as secondary objectives, students should be able to:
   • Understand the historical context in which these theories were proposed.
   • Discuss the scientific evidence that supports or refutes each theory.

The teacher will then take a few minutes to gauge the students' current knowledge on the topic by asking a few preliminary questions. This will help in understanding their starting point and will guide the navigation of the rest of the lesson.

Introduction (10 - 12 minutes)

The teacher will:

1. Recap on the previous lessons on the basic concepts of biology, reminding students of the concepts of genetic inheritance, adaptation, and species diversity. This will serve as a foundation for understanding theories of evolution.

2. Present two problem situations as starters:

   • "Imagine you are a species of bird living on an island where the main source of food is nuts with hard shells. Over time, what changes might occur in your species in order to survive and why?"
   • "Think of a long-necked animal like a giraffe. How would you explain how giraffes evolved to have long necks based on what you already know about adaptation and inheritance?"

3. Contextualize the importance of the theories of evolution by explaining how they have shaped, and continue to shape our understanding of biology. For instance, the teacher can discuss how these theories influence our understanding of antibiotic resistance in bacteria or the development of vaccines.

4. Introduce the topic in a way that sparks the students' interest:

   • Share the story of Charles Darwin's voyage on the HMS Beagle, highlighting his observations on the Galapagos Islands that led to the development of his theory of natural selection.
   • Share a curiosity about Jean-Baptiste Lamarck, who was one of the first to propose that species can change over time, even though his mechanism (inheritance of acquired characteristics) was later disproven.
   • Discuss real-world applications of these theories, such as selective breeding in agriculture or the development of drug-resistant strains of diseases.

These activities aim to capture the students' attention, introduce the topic in an exciting way, and provide the necessary context for the development of the theory to follow. By the end of this stage, students should be eager to delve deeper into the theories of evolution proposed by Charles Darwin and Jean-Baptiste Lamarck.

Development (20 - 25 minutes)

The teacher will:

1. Begin the development phase of the lesson by defining evolution as "a process that results in changes in the genetic material of a population over time" and emphasize that it is a central concept in biology.

2. Present Charles Darwin's theory of evolution:

   • Explain that Darwin's theory of evolution is based on the principle of natural selection (10 - 12 minutes):
     • Define natural selection as the process where organisms with traits better suited to their environment are more likely to survive and pass on these advantageous traits to their offspring.
     • Illustrate this with an example, such as: "Individuals of a bird species with a larger beak size may have a better chance of cracking open hard nuts and thus surviving in an environment where hard nuts are the main source of food. Over generations, the birds with the larger beaks will be more common."
     • Highlight that the key points of Darwin's theory of evolution are the existence of variation, natural selection, and the slow rate of evolution through many small changes accumulated over a long period of time.

3. Discuss Jean-Baptiste Lamarck's theory of evolution:

   • Explain that Lamarck's theory is based on the principle of the inheritance of acquired characteristics and use of disuse (10 - 12 minutes):
     • Define this principle as the idea that an organism can change during its lifetime in response to its environment, and those changes are then passed on to its offspring.
     • Illustrate this with an example, such as: "According to Lamarck, a giraffe may have evolved a long neck because its ancestors stretched their necks to reach leaves higher up in trees, and then passed this long neck trait on to future generations."
     • Highlight that Lamarck's theory was disproven, but was significant for proposing that species are not fixed and can change over time.

4. Have students come to the front of the room and demonstrate the two theories using large diagrams and props. For example, students can use different lengths of string to demonstrate the long neck of a giraffe according to Lamarck, and different size "beaks" (perhaps clothespins or tweezers) to demonstrate Darwin's idea of natural selection in various bird species.

5. Finish the development phase by comparing and contrasting the theories of Darwin and Lamarck:

   • Discuss how both theories acknowledged that species change over time, but had different proposed mechanisms.
   • Highlight the current scientific consensus and evidence supporting Darwin’s theory, and discuss why Lamarck's theory was largely discredited.

Throughout this stage, the students will actively interact with the teacher by asking questions and participating in demonstrations. The teacher will also ensure that the pace of the class is suitable for all students, taking time to answer any questions and ensuring the content's understanding before moving on to new concepts.

Feedback (5 - 6 minutes)

The teacher will:

1. Commence this stage by revising the main points covered during the lesson, ensuring that the students understand how Darwin's and Lamarck's theories of evolution tie into the broader concept of biological evolution.

2. Initiate an interactive discussion to help the students connect the theories of evolution with real-world scenarios. The teacher can:

   • Revisit the examples used in the lesson (birds with different beak sizes, giraffes with long necks) and ask the students to hypothesize how these animals would evolve in different environmental conditions.
   • Discuss current events or recent scientific discoveries related to evolution. For instance, the rise of antibiotic-resistant bacteria could be used as an example of natural selection in action in the modern world.
   • Encourage students to think about how the theory of evolution might apply to human beings, acknowledging the ongoing debates and controversies surrounding this topic.
   • Engage a discussion about other species and how they might have evolved according to Darwin's theory, allowing students to apply their new knowledge to unique scenarios.

3. Encourage students to reflect on their learning by answering the following questions:

   • What was the most important concept learned today?
   • How do Darwin's and Lamarck's theories of evolution differ?
   • Why is Darwin's theory of evolution accepted by the scientific community while Lamarck's theory is not?
   • What questions remain unanswered or what aspects of the topic would you like to explore further?

4. The teacher will then collect these reflections and provide comments or further explanations where necessary. This will ensure the consolidation of learning and can also provide the teacher with feedback on areas that may need further clarification or reinforcement in future lessons.

5. Conclude the lesson by summarizing the importance of understanding different theories of evolution as it provides a deep understanding of the nature of life, biodiversity, and the inter-connectedness of all living organisms.

Throughout this stage, the teacher will use open-ended questions to assess students' understanding and to encourage them to think critically about the theories of evolution. The teacher will also ensure that all students have an opportunity to share their reflections, creating an inclusive learning environment where all thoughts and opinions are valued.

Conclusion (5 - 7 minutes)

The teacher will:

1. Summarize the main contents of the lesson, revisiting the theories of evolution pioneered by Charles Darwin and Jean-Baptiste Lamarck. It is important to emphasize Darwin's concept of natural selection and Lamarck's idea of inheritance of acquired characteristics, along with the historical impact and relevance of these theories.
2. Highlight how the lesson has connected theory, practice, and applications. The teacher will recap the practical examples used to illustrate the theories and how they were applied to understand the evolution of different species. The teacher will also remind students about the real-world applications of these theories, such as the development of vaccines or understanding antibiotic resistance.
3. Suggest additional materials for further study and comprehension. This could include scientific articles, documentaries, or books on the topic of evolution. For example, the teacher could recommend BBC's "Planet Earth" series for students interested in exploring the diversity of life on Earth or "The Origin of Species" by Charles Darwin for those who wish to delve deeper into Darwin's theory of natural selection.
4. Finally, the teacher will underline the importance of understanding evolution for everyday life. The teacher will explain that comprehending these theories can help us make sense of the diversity of life we see around us, understand the spread and evolution of diseases, and even contribute to the development of new technologies and treatments in medicine.

By the end of this stage, students will have a clear understanding of the lesson's content, its practical applications, and the significance of understanding evolution in their everyday lives. They will also be equipped with recommendations for additional resources to further explore and deepen their understanding of the topic.