Reasons for maintaining biodiversity (OCR A-level Biology)

This lesson describes the ecological, economic and aesthetic reasons for maintaining biodiversity. The PowerPoint and accompanying resources are filled with real-life biological examples and have been designed to cover point 4.2.1 (g) of the OCR A-level Biology A specification.

Many hours of research have gone into the planning of the lesson so that interesting examples are included to increase the relevance of the multitude of reasons to maintain biodiversity. These include the gray wolves and beavers of Yellowstone National Park and the Za boabab in the Madagascar rainforests as examples of keystone species. Students will learn that these species have a disproportionate effect on their environment relative to their abundance and exam-style questions and guided discussion periods are used to challenge them to explain their effect on other species in the habitat. The OCR exams have a heavy mathematical content and this is reflected in this lesson as students are challenged to complete a range of calculations to manipulate data to support their biological-based answers. All of the exam questions that are included throughout the lesson have mark schemes embedded into the PowerPoint to allow the students to assess their progress. Moving fowards, the economic ans aesthetic reasons to maintain biodiversity are considered, and there is a focus on the soil depletion that occurs when a continuous monoculture is used. The 1 Billion tree scheme that began in New Zealand in 2018 is introduced and the reasons that some groups of people are objecting to what they consider to be a pine monoculture are discussed. Students will recognise that the clear felling of the trees dramatically changes the landscape and that the increased runoff that results can have catastrophic affects for both aquatic life and for humans with floods.

A number of quiz competitions are included in the lesson to introduce key terms in a fun and memorable way and some of the worksheets have been differentiated to allow students of differing abilities to access the work