# Explain why maintaining high biodiversity is important for the long-term survival of ecosystems.

> WJEC GCSE Biology (Wales) — 2.1.2 Biodiversity · Explain · 4 marks

> Scientists have warned that human activities are reducing biodiversity across the planet at an unprecedented rate. Many ecologists argue that losing biodiversity puts entire ecosystems at risk of collapse.

## Mark scheme (4 marks)

1. A greater variety of species means more food sources are available within food webs
2. If one species is lost, other species can rely on alternative food sources / the ecosystem is less likely to collapse
3. A greater variety of species / genes means populations are more likely to be able to adapt to environmental changes
4. Many species provide resources / medicines / materials that humans depend on, so losing biodiversity threatens human welfare

## Key terms

- [biodiversity](https://www.gradenine.co.uk/glossary/biodiversity)
- [ecosystem](https://www.gradenine.co.uk/glossary/ecosystem)

## Related

- [Revision notes for WJEC GCSE Biology (Wales)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/explain-why-maintaining-high-biodiversity-is-e7f24752) · Published by Druglandscape Ltd.