# Explain how niche differentiation can arise between two populations of the same species that have become geographically isolated from one another.

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

## Mark scheme (4 marks)

1. Geographic isolation prevents gene flow between the two populations.
2. Each population experiences different selection pressures / environmental conditions in its respective habitat.
3. Natural selection favours different adaptations / alleles in each population, leading to divergence in morphology, physiology or behaviour.
4. Over time, the populations occupy different ecological niches as they use different resources, tolerate different conditions, or exploit different prey / food sources.

## Key terms

- [niche differentiation](https://www.gradenine.co.uk/glossary/niche-differentiation)

## 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)
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Source: [GradeNine](https://www.gradenine.co.uk/q/explain-how-niche-differentiation-can-arise-8f43d330) · Published by Druglandscape Ltd.