# Explain how the ecological niche of a specialist species makes it more vulnerable to extinction than a generalist species when environmental conditions change.

> IB DP Biology Standard Level (2023 syllabus) — B4.2 Ecological niches · Explain · 4 marks

## Mark scheme (4 marks)

1. A specialist species has a narrow ecological niche, meaning it relies on a limited range of resources or conditions.
2. If environmental conditions change, the specialist's specific required resources or conditions may no longer be available.
3. A generalist species has a broad ecological niche and can exploit a wide range of resources or tolerate a wide range of conditions, so is more likely to survive environmental change.
4. The specialist has limited ability to switch to alternative resources or habitats, so population size declines and extinction risk increases.

## Key terms

- [ecological niche](https://www.gradenine.co.uk/glossary/ecological-niche)
- [specialist species](https://www.gradenine.co.uk/glossary/specialist-species)
- [generalist species](https://www.gradenine.co.uk/glossary/generalist-species)
- [extinction](https://www.gradenine.co.uk/glossary/extinction)

## Related

- [Revision notes for IB DP Biology Standard Level (2023 syllabus)](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-how-the-ecological-niche-of-b3f479a6) · Published by Druglandscape Ltd.