MYP Biology: Biodiversity & Conservation FAQ

You need three things: the levels of biodiversity (genetic, species, ecosystem), the human causes of biodiversity loss (habitat destruction, pollution, invasive species, climate change, overexploitation), and at least one worked conservation strategy — usually a named protected area or breeding programme you can discuss with real evidence.

Biodiversity is the variety of life measured at three levels — genetic diversity within a species, species diversity within an ecosystem, and ecosystem diversity across a region. MYP Biology expects you to distinguish these and explain why losing diversity at any one level weakens an ecosystem's resilience to change.

High biodiversity makes an ecosystem more stable and resilient — more species means more redundancy, so if one population crashes (disease, drought), others fill its ecological role and the system keeps functioning. Low biodiversity ecosystems, like monoculture farmland, collapse faster under stress because there's no backup.

The main drivers are habitat destruction and fragmentation, pollution (including plastic and agricultural runoff), climate change shifting species ranges, invasive species outcompeting natives, and overexploitation through hunting, fishing or logging. Most IB-style questions want you to explain the mechanism behind one driver, not just list all five.

In-situ conservation protects species within their natural habitat — national parks, marine reserves, wildlife corridors. Ex-situ conservation removes species from their habitat for protection — zoos, seed banks, captive breeding programmes. MYP questions often ask you to evaluate which is more appropriate for a given species, so know the trade-offs.

Simpson's Diversity Index uses the formula D = 1 − Σ(n/N)², where n is the number of individuals of one species and N is the total individuals of all species. A value closer to 1 means higher diversity; closer to 0 means one species dominates the community.

Pick something measurable and local: species richness in two different quadrats (shaded vs sunny), the effect of a pond's water quality on invertebrate diversity, or comparing biodiversity index values across a school garden and a paved area. Avoid topics you can't collect real data for — examiners mark data quality heavily under Criterion C.

Biodiversity typically appears under Criterion A (Knowing and Understanding) for explaining concepts and calculations, and Criterion D (Reflecting on the Impacts of Science) when you evaluate conservation strategies or human impact on ecosystems. Some units also assess it through Criterion C if you design a field investigation.

Expect 'explain' (give reasons with a mechanism), 'evaluate' (weigh strengths and limitations of a conservation strategy), 'discuss' (present multiple viewpoints, e.g. economic vs ecological), and 'calculate' (Simpson's Index or population data). 'Evaluate' questions cost the most marks and are where students lose points by only describing, not judging.

MYP biodiversity work builds directly into DP Biology's ecology topic, where students study community ecology, species diversity indices and conservation in far greater quantitative depth. According to the IB, first exams for the current DP Biology guide were 2025, and ecology now sits within a topic that also covers climate change impacts on ecosystems.

Even outside DP Biology, this unit builds skills examiners value across the MYP sciences: interpreting data, weighing evidence for a judgement, and connecting science to real ethical trade-offs. Those are the same skills assessed in DP Environmental Systems and Societies and in the Extended Essay, so the unit has value beyond one subject.

Look for resources with topic-specific practice questions on diversity indices, past-paper style Criterion D evaluation questions, and clear worked examples of in-situ vs ex-situ case studies. On revisionprep.com, the MYP Biology Revision Notes and Topical Worksheets cover this unit with exactly that structure, alongside a searchable question bank for extra practice.